Sunday, December 30, 2007

Foggy & Getting Colder!

The last several days across the state have been quite gray and dreary looking for the most part. Despite some snowfall over portions of the state, it has been foggy or there has been blowing snow that has never allowed visibilities to go much more than a couple of miles. This fog got very dense last night across much of northwest and north-central Iowa, prompting the NWS offices to issue a dense fog advisory as visibilities were down to near zero! This fog continue through the night across the area, with so much moisture in place allowing snowfall to occur that stuck to everything. Trees are coated with this thick wet snow, along with everything possible seems to have a coating. This fog is likely to continue through the day over some areas of the state, with more snowfall moving in by nightfall.

This light snow may occur across portions of the state, not much accumulation expected anywhere. Western to central Iowa seeing a half-inch to near inch and eastern Iowa also seeing around an inch of snow during the day on Monday. After this quick clipper system moves through, pulling the cold front with it we can expect temperatures to drop into some very chilly ranges. Highs Monday in the near 20 to near 30 range from northwest to southeast, lows from near zero to mid teens. By Tuesday, highs will struggle to get out of the single digits in northwest Iowa with the rest of the state not doing much better only getting into the teens. Tuesday night will start the year off on a very cold note, wind chill values for the morning will be well into the negative teens and twenties over the state. Actual temperature values for when you wake up on Wednesday will range from near zero in the southeast to near -10 in the northwest!

Luckily these temperature won't last long, as the trough responsible for these will move off to the east during mid-week. By Thursday and Friday you can see highs rising into the mid 20s to mid 30s and then even higher into the lower 40s for the southwest. Currently there isn't much mention of precip after the early week system and blast of cold air. Enjoy the cold start to the year, but remember it only gets warmer! Have a happy new year!

Friday, December 28, 2007

Snow Advisory: Dec. 28

A Snow Advisory has been issued for roughly the southeastern half of the state, areas east of a Nebraska City, NE to Prairie Du Chien, WI. Areas just to the west of this line may still see snowfall, but generally around an inch or less of snow accumulation is expected. Those counties that are within the snow advisory are expected to see 2-6 inches of snowfall, with the heaviest amounts in southeast and east-central Iowa.

Latest models have actually indicated less snowfall with this system than previous ones, at least looking at last nights model run. The off-hour model runs that come out during the late night hours also seem to have pulled back on total accumulations. However this doesn't seem to be enough to deter the NWS offices from pulling back some of their forecasted totals. Latest discussion indicates mainly 1-5 inches within their advisory area, which is still going with the latest forecast and advisory text.

Road conditions are likely to be effected by this system, in fact a majority of the state have at least wet conditions due to frost and snow. Areas of southern and eastern Iowa are likely to see mostly covered roads through the Noon hour until the snow can begin to taper off and the plows can truly plow the roads. Take some time when traveling this morning and even this afternoon as some slick areas may still exist.

Thursday, December 27, 2007

Winter Storm: Dec. 27-28

Yet another low pressure system is going to make its' way across the plains states, leading to another shot at heavy snowfall over portions of the state of Iowa. Snow should begin to enter the state late this afternoon and throughout the night, lasting into the daytime hours tomorrow for much of eastern Iowa along with some flurries left over for southern Iowa. Areas of the state have been put under a Winter Storm Watch that will likely be upgraded to at least a Snow Advisory later this afternoon. Areas currently not under the watch may still be upgraded to some sort of advisory as the path of this system may go slightly north than the Des Moines forecast office has indicated with their watch area. Models are in line fairly well with the track and amounts from this system, the area of more than 1 inch of snow should be east of a line from Nebraska City, NE through to Rochester, MN. Areas west of that line are likely to only see snow flurries with accumulations less than an inch.

Amounts east of that line area likely to range from 1" to upwards of 5" with some half-foot amounts possible in some of the heavier bands of snow. The Davenport NWS has put wording in their forecast that isolated 5-8" amounts are not out of the question. Models currently paint the heaviest snowfall amounts between 5" and 7", this mainly in areas of southeastern and eastern Iowa. For the latest information on the expected amounts check out the 'weather story' feature on the DMX and DVN NWS pages that are linked below:

Des Moines NWS Weather Story
Davenport NWS Weather Story

Tuesday, December 25, 2007

Christmas Snow Advisory

There has been slight chances of snow in the forecast for Christmas for the past couple of days, but it now looks like areas of at least northwest Iowa will be receiving plenty of Christmas Snow. This area of the state missed out on the snowfall from the previous system that dumped over a half foot of snow in southern and eastern Iowa. Light to moderate snow showers have continued to spread southeast into northwest Iowa this afternoon. Enough moisture has pooled up to prompt the NWS out of Sioux Falls to issue a Snow Advisory for their northwest Iowa counties. The band of snowfall should continue to work southeast through the evening and into the early nighttime hours, a total of 2-4 inches of accumulation are likely in the areas under the snow advisory. This advisory essentially includes counties west of highway 4 and north of highway 20...

Areas that are near this snow advisory will still likely see snowfall accumulations this afternoon and tonight, however total amounts should generally be 1-2 inches. This snowfall may also continue to work into the rest of the state overnight and into tomorrow. Current forecasts only put ~1 inch of accumulation over the rest of the state, although I would not be surprised to see some isolated higher amounts. Some areas of the state may also escape this system with little or no accumulation, but a generally light snowfall should occur over a majority of the state.

Hope everybody enjoys their christmas snowfall, happy holidays!!

Saturday, December 22, 2007

Winter Storm: Dec. 22-23

The winter storm that was expected to begin as early as last night has held off its' punch until this afternoon as heavy snows are beginning in southern Iowa. Last night saw a few stray snow showers make their way through the state, with little accumulation for most areas. The bands of snow around the low pressure system have entered the state early this afternoon and as of the latest radar updates some heavy snow has came into south-central Iowa extending to the Iowa City area.

The Winter Storm Warnings and Snow & Blowing Snow Advisories that were issued last night have been extended until the morning hours tomorrow as this snow has been slow to make its' way north. Travel conditions are becoming unfavorable over some areas of the state as shown by the road conditions link. Some areas within this heavy snow and winds are producing white out conditions as shown by the webcams across the state.

Current snow totals are going to range from 4-8 inches along the heaviest bands of snow that are likely from south-central Iowa into northeast Iowa. Areas both east and west of that line can see 1-3 inches of snow this evening and overnight, while areas of northwest and a majority of the western third of the state won't see much of any accumulation. For the latest updates be sure to check out the NWS pages as well as the road conditions maps across the state. This storm isn't effecting me much at all in northwest Iowa, thus I've been busy with other projects. A recap of the storm may be posted tomorrow or at a later date as it looks to be a pretty good near blizzard storm.

Friday, December 21, 2007

Winter Storm: Dec. 21-22

Portions of the state are going to be in for a nice winter storm that will effect a lot of their weekend travel. The storm system that has been talked about since the beginning of the week has finally came into focus, providing a forecast that puts portions of the eastern third of the state under a half foot of snow! Other areas of the state are going to see general amounts of snow in the 1-3 inch range.

A low pressure system is likely to develop along the IA/MO borders late tonight and continue to strengthen as it moves northeastward towards the Great Lakes area. This low will setup a strong pressure gradient and thus some fairly gusty winds over much of the state tomorrow. This wind will be accompanied by moderate to heavy snow over central and eastern Iowa, light to moderate snow over western Iowa. All portions of the state may see some hazardous driving conditions when under the snow showers as wind gusts are likely to blow the snow around quite easily during and after its' fallen. Eastern Iowa will see the heaviest snow bands as it remains within the lows' deformation zone, allowing for slow moving bands of heavy snow. Total accumulations in the 4-8 inch range are going to be possible, with some locally higher amounts not out of the question in eastern Iowa.

Central Iowa will likely be within a 2-5 inch range of snowfall and western Iowa within a 1-3 inch range of snowfall with areas along the Missouri seeing under an inch in some locations. Where snow does occur expect some slow travel as mentioned the winds will provide some blowing and drifting snow to occur. Currently only winter storm watches have been issued for portions of central/eastern Iowa, expect those to be upgraded later this afternoon. The latest weather story from Des Moines gives a rough estimate of snowfall forecasted:

Wednesday, December 19, 2007

Weekend Winter Storm Potential

Latest model runs continue to put this system up in limbo, but a little more consistency in some models are leading to a slightly better idea than yesterday. Current thoughts conclude that this system may be much quicker in moving across the plains as the low develops over the plains and slides into the Great Lakes. This low is still expected to become quite strong over the Great Lakes, but with its' speed moving across the plains it likely won't have such of an impact as previously thought.

Snowfall across Iowa is still likely, with some mixed precip still possible over southern and eastern Iowa as well. Snowfall amounts and overall precip amounts aren't likely to be too excessive, general forecast puts 1-3 inches across much of the state in snowfall amounts. This is a quick and general belief in what the current models seem to be displaying and what NWS offices seem to be going with. A more precise and likely more accurate of snow amounts along with the chances of any mixed precip will be known in later updates. Still should keep an eye on the storm, but it does look like the severity of the storm will not as crippling as previous forecasts may have indicated.

Tuesday, December 18, 2007

Potent System for Weekend

As mentioned in the previous post, this weekend holds some potential for a significant winter storm to go over the plains states. This system has been featured in the models for a while, but the exact location of this system has still been in limbo even in current forecasts. Nonetheless, the latest consensus is to bring a low pressure system out of the Rockies just south of Colorado and into the plains by Friday night. This low pressure system continues to the northeast moving near the MO/IA border by Saturday morning and then up towards the Great Lakes by Sunday. This low pressure system is accompanied by a very strong trough which will allow the low to strengthen considerably as it moves over the plains on Saturday into Sunday. Stronger low will likely mean a better chance for significant precip amounts not only along the fronts south/east of it but especially areas that are just north of the front where the deformation zone is setup. One thing this strong low will definitely bring with it is stronger winds, latest forecast discussion from Des Moines has pointed out that on the backside of the low may create blizzard conditions over Iowa.

This track just to the south of northern Iowa is likely to bring some of the heavier snow amounts to the area. Although any change with the track will of course bring a change to where the heaviest snow amounts fall. Areas that receive this heavy snow are likely to not only get the snowfall, but winds to go with it as a strong pressure gradient is likely to setup west of the low. Luckily this low is conjoined with the strong trough in the upper levels, meaning it won't stick around for long. Current timing of this system looks to effect Iowa mainly on Saturday, of course dependent on the amount of snow and wind behind it means it could continue to have some problems with transportation on Sunday while things get cleared off.

Other areas of the state may not only see the snow, but some mixed precip types are going to be possible along and just to the south of the low. A strong low means strong temperature gradients are likely to be present, meaning that some fairly warm temperatures are likely just to the east and south of the low. Freezing rain, sleet and even rain are all going to be possible along the plains states as this system is going to bring up that warm air to various areas along its' path.

Not going to get into the issue of how much snow and the exacts on locationing of this storm as it is still just too far out in the forecast. Would of course recommend a very close eye on this system as the weekend is likely one of the busiest of the year with Christmas coming next Tuesday. Will continue to have updates, hopefully daily, as to what the latest forecasts indicate with this system.

Sunday, December 16, 2007

A Nice Week... Website Changes

First off, a quick note on some website issues. My gallery pages as you may have noticed are not operational at the moment and I'm currently in the process of unveiling an entire new website and design. I hope to have the new gallery operational by the new year, along with the remainder of the website. Keep checking back here for the latest details and the word on the official unveiling of the new website.

Now to the weather for the week, the last full week of work for most people as Christmas is nearing ever closer. A mainly dry week in store for the state, although a small system may get portions of the state Wednesday night into Thursday. The main focus for a winter storm is currently looking at this weekend, as another potent low may effect the state. Some areas of eastern Iowa are seeing flurries today, Thursday over central & eastern Iowa may also see some flurries or drizzle; neither of these events should be much.

Temperatures throughout the week will be fairly mild, mid 20s to lower 30s on Monday with warm-up continue through Thursday with highs mainly in the upper 20s to mid 30s across the state. Lows in the single digits to lower teens tonight, but a quick change into the mid teens to lower 30s should take place by Monday night. Lows should remain in the mid teens in the north to the mid 20s in the south throughout the week before this weekends storm starts to effect the state.

More information on this weekends storm will be available in later updates...

Saturday, December 15, 2007

More Snow!

The whole state doesn't have to worry about it, but portions of southern and eastern Iowa will definitely be on the lookout for some significant accumulations. A winter weather advisory is in effect for areas south of a Nebraska City to Des Moines to Dubuque, 2-5 inches of snowfall is likely in those areas. Areas just north of that line may see light snow with some accumulations of less than 2 inches. Some portions of south-central Iowa may see even higher amounts than the rest of the state, areas including Lamoni and the surrounding counties may see snowfall of up to 7 inches! These areas have been upgraded to a Heavy Snow Warning until mid-afternoon today, as snowfall rates may be several inches per hour.

The remainder of the state that won't have this snow to deal with will see a nice day, with the sun shining for most of northern Iowa. Temperatures across the state will range from the lower to mid 20s today. Lows tonight will range from the single digits to the mid teens over eastern Iowa where some cloud cover will still be present.

For the latest information on the advisories and warnings, including the texts see the Winter Weather Page from Des Moines NWS.

Thursday, December 13, 2007

Semester Nearly Over!

I'm currently in my 5th semester of studies at Iowa State University in Ames, Iowa. That is until about 5 hours from now when I will be finishing up my final exam in Surface Hydrology & Surficial Processes. Once that is complete I will be completed with all of my work this semester and can start thinking ahead on my 6th semester here at Iowa State... For those of you who don't know more about me, I am a Meteorology major and a Geology minor; my Geology minor is emphasized on the hydrological aspects of things. This semesters classes included Statistics, Atmospheric Physics, Synoptic Meteorology, History of the Earth (Geology) & the Surface Hydrology/Surficial Processes course. All of them will of course get a passing grade from the work I've done, in fact going through my grades it looks like this may be my best semester since my 1st one down here in Ames. I thank that upon finishing up my work in Calculus and Physics!

Anyway, just thought I'd give a small update on some of the ongoings as to why I've been so busy lately. I'll have another post about school maybe once I receive my final grades this semester or before next semester begins with a little preview of what I'll be handling then.

Oh, as for the weather, didn't think I'd leave that out, did ya? It looks to be a fairly nice end of the week into the weekend, with temperatures in the mid 20s to mid 30s across the state for highs, lows ranging a little wider from the teens to a few single digits possibly. Only snow in the forecast may come Friday night into Saturday, this won't be much of anything accumulation-wise as flurries are really the only mention in the forecasts. Look forward to a nice weekend, get out and enjoy all of the snow that is around; also a great time with the sun out to melt any of that ice that you still have left on the driveway or other areas!

Monday, December 10, 2007

Winter Storm: Dec. 10-11 -- Storm Updates

9:00 PM - The freezing rain and sleet has ended for much of the state, at least the majority of accumulations have already occurred. Light freezing drizzle and/or snow may still occur over the next several hours as the moisture continues to be rung out of the atmosphere. Areas of southern and eastern Iowa are still without power and may be so for a couple of days; although much of the effect should be limited to cleaning up tree branches and scooping/scraping the sidewalks and driveway. Here is the latest update from Des Moines on what the state saw for accumulations:

Noon - The precipitation is beginning to move on, much of the western half of the state will likely only see flurries or light drizzle if anything for the remainder of the afternoon. Areas of eastern Iowa are still in the path of the surging moisture however and can expect to see the freezing rain, sleet or snow continue into this evening.

The latest map from the Des Moines NWS can give you an idea of how this storm turned out, a very sharp gradient from freezing rain to snow/sleet as Ames was acquiring mainly snow this morning while just to the south in Ankeny they were adding freezing rain on top of what they already had. This map was last updated over an hour ago, some of the details aren't great, as Ames does have over an inch of snow as well as the tenth of freezing rain that fell overnight. Once this storm has completely came to an end a complete wrap up of the storm will be posted... However, eastern Iowa still on the lookout for continued freezing rain accumulation while the western half finally begins to dry out.

6:15 AM - Freezing rain has continued throughout the night over portions of southern Iowa that are under the Ice Storm Warning. Other portions of the state have seen scattered showers capable of freezing rain, sleet or snow in some cases. Currently radar indicating that another patch of moderate showers is moving into southwestern Iowa and will continue to expand and move northeastward. Latest RUC model forecast for the short term today indicates light to moderate showers are expected over much of the state, with the potential still for some fairly heavy bursts in embedded storms...

Latest short term forecast from Des Moines touches on the fact that we should expect precip to expand and overtake much of the southern half to two-thirds of the state within the next 2 hours. Additional freezing rain likely south of I80, upwards of a half-inch of ice accumulation; while north of I80 can expect mainly sleet/snow to fall with accumulations of 1-3 inches.

Reports are beginning to come in this morning as people wake up and take a look at what they have received overnight. NWS Office in Johnston reports .2 inches of ice, Centerville & Ottumwa both report .5" of ice and a report from Bedford indicates that power outages have occurred in some portions of the state. Additional reports from the Des Moines Airport indicate that nearly .4" of ice has fallen there, Atlantic reports of a quarter inch of ice. The only snow report thus far comes out of Sioux City where they have received just under 2 inches of snow overnight. Expect reports to really pour in this morning, you can read the latest ones by viewing the 'local storm reports' links to the right. Next update likely to come during the early afternoon hours, after I've finished with my two finals tests for today!

10:30 PM - Likely the only update for tonight, freezing rain has surged northward this evening and is already as far north as a Harlan to Winterset to Albia line in southern Iowa. Freezing rain is likely to accumulate rapidly as moisture is plentiful and showers are likely to have decent rain rates. Some reports from southeast NE and southwest IA where the freezing rain began only an hour to an hour and a half ago indicate that accumulations are already nearing a quarter of an inch. Expect freezing rain to continue to push north and east into much of the southern half of the state by the early morning hours. By sunrise tomorrow could expect to see much of the state receiving some precip, with snow mainly north of a Omaha to Dubuque line; south of that line a mix of precipitation could be seen. Once south of a Nebraska City to Davenport line it is likely that you may be seeing freezing rain throughout the night and well into tomorrow...

Total accumulations with this storm do not look to be overdone at this time, previous storms have lacked some conditions to give them their full potential. Currently it looks as if this storm may truly produce upwards of an inch of ice for portions of the state and other states including KS/MO and IL into tomorrow evening. Areas of Oklahoma have already received extreme amounts of ice and put over a half a million people without power. Estimate will likely have that number over a million by sunrise and we could be into multiple millions of people without power by this time tomorrow evening.

I do have radar updating on my homepage, radar colors will stay in regular reflectivities as the mixed precip is likely to show up better with it rather than the winter reflectivity colors you may have saw last time. For the latest in the warnings/advisories that the NWS has issued please check out the links to the right of the posts. Also keep in mind the road conditions over the state, that link is also posted to the right. Next update likely to come very early tomorrow morning, subsequent updates not likely until afternoon tomorrow.

Winter Storm: Dec. 10-11 -- Update #2

Afternoon Update: Models from this morning went slightly warmer, or at least the WRF went warmer to become more in line with the GFS as far as snowfall production went. Looked over several of the atmospheric profiles this afternoon with several other meteorology students here at Iowa State and the consensus seems to be that this is a challenging forecast on precip type. Any slight changes in the temperatures anywhere below 700mb is likely to results in different precip types. The forecast from this morning still seems to be going fairly well, the location and timing of the system still seems to be good. One likely change will be to include the snow & sleet accumulations together; read snow/sleet accumulations of 2-6 inches combined. The center area will also likely see anywhere from a tenth of quarter of an inch of ice as well before the sleet/snow begin Tuesday morning. Of course as you reach further north/west to the line expect only 2 inches of sleet/snow with little ice accumulation. The south/eastern portion of the state still seems likely to have dramatic ice accumulations, with some forecasts indicating over an inch of ice accumulations. Therefore storyline of significant winter storm still going, areas of Oklahoma already saw some significant ice before it turned to rain this morning. Expect the remainder of the plains to get into the action by tomorrow morning...

Morning Forecast: Upgrades from the winter storm watch are continuing this morning, areas of southeastern Iowa are now in a Ice Storm Warning, other areas of southern Iowa are in a Winter Storm Warning and just to the north and east of that will likely be a Winter Weather Advisory. Cities under the Ice Storm Warning include Lamoni, Ottumwa, Davenport, Burlington and Keokuk. Those cities are expected to receive a half inch to over an inch of damaging ice accumulation, beginning tonight and lasting into Tuesday before a change to a sleet/snow mix may occur late Tuesday afternoon. The Winter Storm Warning includes Omaha, Atlantic, Des Moines, Ames, Marshalltown, Cedar Rapids & Iowa City. Areas within this stretch of the storm are expected to incur some freezing rain and/or sleet tonight before a change over to snow occurs Tuesday morning. These areas could receive up to a third of an inch of freezing rain, or one-half to an inch of sleet accumulations during the overnight. By Tuesday, the snow could accumulate from around an inch to upwards of 5 inches! The Winter Weather Advisory has been issued for portions of the state further north, more counties are expected to be included later this morning. These areas may receive some light ice/sleet accumulations before seeing all snow by Tuesday; total snow accumulations still likely into the 2-5 inch range.

For the latest map on the advisories/warnings, check out the Des Moines Winter Storm Page. A rough map of my current forecast is below:

Sunday, December 9, 2007

Winter Storm: Dec. 10-11

Another winter storm is taking aim at the central plains and unfortunately this storm is going to be one that once again is bringing a mixture of precipitation types to the state. A Winter Storm Watch has been issued for areas of Iowa mainly south of I80, to keep up on the warnings check out the link that was provided previously as well as the map on the Des Moines Winter Storm Page. The possibilities with this storm includes a mixture of freezing rain, sleet and snow; with up to a half inch or more of ice accumulation along with up to an inch of sleet and a couple inches of snow. Many possibilities still exist as the exact location of the storm as well as precip type, much like the last storms to hit the state. This event should begin Monday night and last through the day on Tuesday, with the bulk of mixed precip actually occurring Monday night. An update on the forecast as well as the watches/warnings will likely be made tomorrow in between my study sessions for finals!

Friday, December 7, 2007

Winter Storm: Dec. 8-9

Winter Storm Recap: Mixture of snow with some freezing drizzle over southern Iowa occurred on Saturday and into early Sunday for portions of eastern Iowa. Snow amounts were heaviest over northwest Iowa and gradually got lighter the further south you went. Looking over the reports on CoCoRaHS from Iowa, the highest report of snowfall came from my house! 5.5 inches of new snow fell on the ground, on top of ~3 inches that was already on the ground making for a nice 8.5 to 9 inch snowpack now on the ground in northwest Iowa. Iowa co-op observers go along with this location of heaviest snow, Sanborn observer reporting 6 inches of new snow. Here are a few maps of the reports:


6:30 PM Update: Snow has been falling over much of the state this morning and afternoon, some hazardous conditions are being noted on the roadways where snow has covered the roads and in some cases a mix of freezing rain or sleet has also occurred. North of highway 30 and west of a Waterloo to Mason City line is still under a Snow Advisory as 3-5 inches of snow are likely to fall by the end of the storm tonight. South of highway 30 throughout the state is a Winter Weather Advisory, areas may see freezing drizzle, sleet as well as the snow. Thus total snow accumulations are only expected to be 1-3 inches. The extreme southeast corner of the state actually has a Freezing Rain Advisory, where a tenth to a quarter of an inch of ice may accumulate.

For the latest reports on snowfall from throughout the state, please click on the local storm report links to the right of the post.


Haven't had a lot of time and thus won't be able to do the complete forecast for this event like I had hoped for. Nonetheless, want to let people know about the upcoming winter storm that will likely effect much of the state, areas of western Iowa have already been put under winter weather advisories, snow advisories and even heavy snow warnings around the Sioux City area where up to 8 inches of snow may fall through Sunday. For the latest watches/warnings that have been issued visit the Des Moines NWS Severe Weather page and click on respective county or any other option. Possible updates later on tomorrow evening may be possible...

It is finals week next week down here at Iowa State, thus updates may cease for a while as I prepare for those. Wish me luck!

Thursday, December 6, 2007

Winter Storm: Dec 6 -- Storm Updates

8:30 PM Update - Snowfall has ceased over areas of western and central Iowa, with only the eastern third of the state still under a Snow Advisory as moderate to heavy snows may occur through midnight. Once into the early morning hours the snow should taper off to only a light snow before stopping completely before the sunrises.

Accumulation totals over the state are highest in the southwest where a few 5 inch totals and even a 6 inch total just east of Tekamah, click to view the Omaha NWS Snowfall Map. Northwest Iowa was less, as the Snow Advisory was even canceled for some portions of the area. Mainly 1-3 inches, although a few 4"+ amounts in Cherokee, Storm Lake and Sioux City; click to view the Sioux Falls NWS Map. Across central Iowa, 2-5 inches of snow fell for a majority of the state with the heaviest surrounding the Des Moines area. A list of the Des Moines NWS reports can be found here. The areas of eastern Iowa aren't completely done with their snowfall, thus no final reports or images are available currently. It is expected that 2-4 inches, isolated 5 inch amounts may occur with a few of the stronger snow bursts.

2:00 PM Update - Snowfall was light in Ames throughout the morning, however latest radar imagery and the view from outside indicate that moderate to heavy snowfall is occurring and going to continue through mid-afternoon over central Iowa. This band of snowfall is working out of eastern NE and western IA where report have nearly 5 inches of snow on the ground in Omaha and 2.5 inches in Sioux City. This snowfall may create some travel problems before the snow stops and crews can completely clear it, take extra precautions when driving.

Mainly an inch has fallen over central Iowa where the snows are finally beginning to fall heavier, eastern Iowa has yet to see more than light snow out of the system. You can view the latest winter weather radar image on my homepage see where the heavier snows are, represented by the brighter blue colors. White reflectivities in this instance indicate mainly light snow, keep in mind this is the Des Moines radar image currently and thus those of you who are in the corner of the state or extreme eastern Iowa may not see reflectivities over them as the radar cannot reach that far.

Iowa Chaser Winter Weather Radar Image
Radar Loop -- Javascript or Flash Player

Wednesday, December 5, 2007

Winter Storm: Dec 6

A winter storm is taking aim at Iowa once again as the active pattern of systems continues... This system is luckily bringing with it only snow, no chances of any other wintery precip types. The snow should begin in western Iowa during the early morning hours and traveling across the state throughout the afternoon hours, ending in the west by mid-afternoon and finally leaving the state just after Midnight. Snowfall amounts should range within the advisory criteria, 2-5 inches throughout the state. Winds should be fairly brisk, in the 15-25 mph range and thus allowing for some blowing snow especially in open areas. Expect some traveling problems if you are out during the morning or afternoon hours, or evening in the east as snow blows across the road and moderate snowfall rates reduce visibilities under a mile. Overall a general winter storm with not much in the way of excess snowfall, but one of the first all snow events that some areas are going to see and thus take it slow the first time around to get used to the conditions...

For the latest Snow Advisory information via the NWS, please check out this link!

Once this storm passes through we will look ahead for this weekend as our next storm arrives. Models have fluctuated with the type of precip, lately they have progressed to an all snow event and this seems to be the going forecast. However, it has also trended towards a weaker solution of only light to moderate accumulations of snowfall. This system will still be watched, however at this time it seems to have lost some of its' potential. More updates on the weekend system in later updates...

Thursday's Potential Snowstorm & A Recap of Yesterday's 'Clipper' Snowfalls

Beginning Thursday morning we should have our next storm system moving into the state, the NWS has begun to issue their Snow Advisories for this storm. To read the latest text for these advisories, please check out the NWS Snow Advisories. This storm is expected to be fairly quick, beginning in western Iowa by the early morning hours on Thursday, but should be out of the state by Midnight that night. Lingering flurries or scattered snow showers may be possible later than that, however nothing significant expected. Updated forecast and status on advisories, etc. will be posted tonight...

Yesterday's quick moving system put down some decent amounts of snow across northeast Iowa, allowed scattered snow showers and rain showers, along with a mix of all precip in between snow & rain across portion of the state. No significant reports of accidents or power outages in Iowa, just north into MN or WI there were however reports of several accidents on I90 and other areas near the Twin Cities. Co-op reports from around the state put the snow northeast of a line from Webster City to Davenport. Highest amounts as noted were in the far northeast corner of the state where several 5 and 6 inch reports came in from observers. This puts snowfall depths in that part of the state nearing double digits, with Waukee actually in double digits with 10 inches of snow on the ground. The current swatch of snowfall actually on the ground comes from near Sioux City, to Carrol and through Boone continuing to the east to Davenport; a majority of locations north of that line currently have snow on the ground.

Monday, December 3, 2007

Some Quick Snow

A quick system is going to work over the state this evening and through the overnight, mainly effecting northeast Iowa. This kind of system is usually called a clipper due to the quick moving nature, often these systems originate in Canada and are called an Alberta Clipper. This case however is not an Alberta Clipper per say, a weak low pressure system is actually going to be located over Iowa and into the Midwest/Ohio Valley. To the north of this low where there is enough energy and cold air to ring out the moisture that is there and give areas some quick snowfall.

Tonights' system may bring some light precip for much of the state, however a bulk of its' energy will be to the north and east of the state. However, northeast Iowa may see some decent snow amounts during the overnight hours. A quick 2-6 inches of snow may be seen over that section of the state, while the rest of the state will likely stay under an inch of accumulation. Areas in the southern half of the state may see a mix of snow/sleet and rain if some precip can occur in those areas. No significant accumulation is expected, however it does not take much of a mix bag of precip to make conditions hazardous. Nonetheless, this system should move through and be gone by tomorrow morning...

For the latest statement by the NWS, read the latest Snow Advisory that is effect from this afternoon through tonight for areas of northeast Iowa.

Temperatures today ranging from the upper 20s in extreme northeast Iowa to the mid 40s in southwest Iowa where there is no snow on the ground. Lows tonight in the teens to upper 20s from north to south. By Thursday we will see our next winter system make its' way over the state, bringing the entire state to a chance of good snow accumulations. This system will be followed by several waves of energy that may bring more winter weather over the state throughout the weekend. More details on the Thursday storm and others following will be posted in tomorrow's update...

Sunday, December 2, 2007

Dec. 1 Winter Storm Recap

Light to moderate snow still making it' way across the state this morning in one last band behind this system which is currently over the Great Lakes and areas south. This storm is going to continue to give winter storm conditions over the northern Great Lakes and into the northeast over the next 48 hours. The storm however has moved past Iowa and other areas of the plains, leaving behind snow, ice and a mixture of everything winter in it' path. North of the IA/MN border and near the IA/SD border and west, mainly snow was received with little in the way of other precip forms. Portions of eastern NE got hit hard with ice/sleet mixtures, others began with ice but melted off before the storm was over due to rain. Iowa was a mixed bag of precip form, snow in the northern half mixed with glazes of ice; a quarter of an inch or more of ice throughout much of the southern half of the state. Some areas receiving over a half of an inch of ice and portion of southwestern Iowa mainly receiving rain.

Travel conditions were strained in the morning hours as mainly ice fell with drivers apparently not noticing the worsening conditions. By early afternoon many portion of the state were out of the 'Travel Not Advised' conditions, all except for east-central Iowa where large amounts of ice were falling. These areas were the main reports of power outages as well, although there were some scattered throughout the state; east-central Iowa was hit the hardest with nearly ~15,000 houses without power for at least some time. One western Illinois town is still without power this morning due to several downed lines; a community shelter was opened up there for people.

As for forecast verification, main problem was not total precip amounts but instead the coverage of those areas. The major pockets of ice were kept into a small coverage area for the most part, instead of being widespread as models were indicating. Also the presence of ice pellets and sleet were much higher than what my forecast indicated, here in Ames a majority of the morning was sleet compared to the expected freezing rain. Snowfall amounts were generally smaller than expected, areas in the northern third of the state received generally 1-3 inches although the northeast corner saw 3-6 inches amounts. Generally however the QPF amounts were above an inch, which is what forecasts were calling for. Main problem with this winter storm was the precip type, which generally is going to be extremely hard when you have this type of system.

Hope readers enjoyed the updates yesterday, the blog was at near-record numbers for visits and page views. We were competing with days in the month of June during TWISTEX, which is quite impressive for a winter storm making a run at severe weather and chasing. Hope many of you continue to come back to read the latest forecasts for the state of Iowa and when that next winter storm is likely to occur. Please, leave comments if you wish! Thanks

Saturday, December 1, 2007

Winter Storm: Dec. 1-2 -- Live Updates

5:45 PM Update: Small band of showers working through central Iowa currently, another small area in northwest Iowa and the strongest band of showers in southwestern Iowa. These patches of precip will put down a wide variety, ranging from mostly rain in the south to freezing rain in the north. Expect other patches of precip to develop throughout the overnight as the low pressure begins to make its' way into the state; there should however not be any significant amounts. General under a tenth of an inch of rain or freezing rain and an inch or so of snow/sleet at most. Some areas of the state due have problems with driving conditions and there are scattered areas without power; current estimates are ~15,000 people without power across the state, a majority of them in eastern Iowa.

Road conditions are mainly wet for the southern third of the state, partially covered in the central, mostly covered in the northwest. Completely covered in north-central and northeast Iowa, with travel still not advised for areas of east-central Iowa including Cedar Rapids, Iowa City and the Quad Cities. Storm has hampered some areas, but definitely not as widespread as forecasted and the hardest hit areas were luckily not as bad as the worst case scenario. Possibly one more update late tonight, otherwise may work on a recap of the storm tomorrow that will be posted.

3:30 PM Update - Light freezing rain still falling in Ames, has really slowed down for the past hour or so and it looks like it will remain light if at all for the remainder of the evening/night. East of I-35 is the only portion of the state that is currently showing reflectivities on radar, small area of precip on the wrap around for the low in northeast NE. That may track over parts of northwest Iowa and give them an extra shot at frozen precip. Warm air is still slowly pushing into the state, may be able to melt off some of the ice on the roadways, especially in southern half of Iowa. East-central Iowa is the only portion of the state that has 'travel not advised' posted; this will likely continue for eastern Iowa through the evening.

The ice storm warning has been cancelled for much of south-central Iowa; the winter storm warning for portions of northwest Iowa has also been canceled. Expect the remainder of the state to slowly see the warnings continue to expire into the evening as this line passes through. For now I'll cease the updates to only every couple of hours, leaving you with a few pictures I grabbed near my apartment here in Ames:

Fallen Tree Branch -- Small Icicle -- Several Small Icicles

2:00 PM - Currently experiencing freezing rain, heavy at times in the past half hour; accumulations occurred quickly on all of the trees, etc. Looks like a good tenth of an inch of frozen rain, slightly less on some trees. This rain did manage to melt into the sleet that was already there, creating somewhat of a frozen slush mixture. This band centered over I35 currently, continuing to move northeast into the mid-afternoon; behind this band it seems to have cleared off precip wise as a dry slot move in ahead of the low. Unsure on any precip chances after this current band works through, likely done in Ames by 3 PM. That update at 3 PM or just before will have the totals thus far, which may end up to be the final totals depending on how the rest of the system moves through.

1:15 PM - Warm air has made its' way into southwest Iowa, as well as southeast NE and the portions of KS/MO. This has prompted the Omaha NWS to cancel the ice storm warning for portions of the state, due to rain likely falling for the remainder of the afternoon and only light precip likely during the overnight hours when some freezing may occur. Much of the ice in the area that has been dropped will likely melt over the next couple of hours as the rain falls. This warm air has however allowed for a large complex of showers and potential rumbles of thunder to move into southern Iowa and is currently working east-northeast into central Iowa. This will have the potential to bring copious amounts of ice/sleet to the area in very little time. Check out the latest radar image on my homepage to view the location of this next round of precipitation... Temperatures are near freezing in front of the complex, sleet or freezing rain potentially turning over to rain if temperatures continue to rise with the system. Either way it is likely to be a mess over the next couple of hours for areas of central/eastern Iowa as it makes its' way through. Next update likely in an hour or so as this round is overhead...

Noon Update: Light sleet still occurring here in Ames, not sure on additionally accumulation as I haven't gotten back outside yet; will likely do that before next update. Warmer air continuing to make its' way into the state from the southwest, air temperatures and surface temperatures are both rising with its' appearance. Not much for additional reports in the past hour, been fairly quiet actually as a band moves into northeastern/eastern Iowa and moves out of the area; looks like western Iowa is fairly precip free for the time being. The next wave of precip is currently working through along the southwestern corner of Iowa and will likely continue east and north; mainly affecting southern Iowa with a round of rain/frz rain or sleet depending on the temperature profile.

11:00 AM: Moderate to Heavy sleet/graupel was coming down in Ames, seems to have let up a bit in the past couple of minutes. Nearly an inch of sleet accumulation on the ground, a couple of hundredths of an inch of ice on cars and other surfaces. Trees don't seem to have much for accumulation, although I'm sure some may accumulate better than others. Roads are slick however, several accidents have been reported throughout the morning with a couple of injuries possible (ambulances on scene, actual extents unknown). Travel is not advised for areas of southcentral, central and eastcentral Iowa currently; the remainder of the state has roads mostly or completely covered. Essentially travel should not be advised no matter where you are in the state, as conditions are likely to worsen into the afternoon. Power outages in some areas of the state have been reported, this may likely continue into the afternoon; latest estimates have total houses in the thousands. Several reports coming in as far as totals go, however conditions changing so rapidly I'm not going to go through a listing; check out the links to the right for the latest local storm reports.

Expecting sleet/frz rain to continue for much of the state, however the warm air has already made its' way into southwestern Iowa with surface temperatures above freezing now. Rain beginning to be reported at some of the stations along the IA/MO and IA/NE borders. This warm air is likely to slowly make its' way into the rest of the state, we'll have to watch closely as this could really improve conditions as areas where rain has begun in eastern NE report that the ice was melting fairly quick even with the cold rain.

9:30 AM: Freezing rain and light snow accumulating on the ground, a couple of hundredths of ice accumulation on trees and other surfaces. Up to a half an inch of the sleet/snow and ice on the ground however. Road conditions continue to deteriorate, however no complete closures as of yet. Highest snowfall reports out of northwest Iowa where up to 1.5 inches of snow in Spirit Lake & Estherville; sleet now the main form of precipitation as of latest reports; freezing rain occurring and accumulations over a tenth of an inch reports in several areas across the state. Next update likely at 11 AM.

8:45 AM: Freezing rain and sleet mixture began ~15 minutes ago in Ames again, quickly accumulating on the surfaces. This is actually occurring quicker than originally forecasted, thus expect travel conditions to deteriorate rapidly this morning and have roads in some areas closed before Noon. Areas now around Des Moines and Ames are now also under 'Travel Not Advised'; I believe I80 in eastern NE is closed already in some areas due to several jack-knifed semis. Ice accumulation fairly rapidly, next update likely ~9:30 AM.

8:25 AM: A good dusting of snow has occurred in Ames with the light precipitation that has been over the area for the past couple of hours. Some freezing rain has also been falling across the state, checking out the webcams across the state you can tell which areas have really received this as the cameras are iced over already. Surface temperatures over southwest Iowa are already near freezing and a couple of readings above freezing, this may likely cause the changeover to rain within the next hour or two. Thus far for road conditions, south-central Iowa is already indicating that travel is not advised, this includes I-35 south of Des Moines (Towing services prohibited). Storm already underway and thus far making a decent impact within hours...