Friday, November 20, 2009

Snow in KC & More...

I spent the day on Monday attempting to forecast the cut-off low pressure system that rolled through Kansas and Missouri, bringing thunderstorms, moderate to heavy rainfall, and some fairly heavy snows to areas along the borders of KS/NE/MO.  This was one very difficult system, with varying temperatures throughout the precipitation bands creating mixes of rain/snow, heavy snow, sleet and just rain.  Parts of northeast Kansas and southeast Nebraska saw as much as 7 inches of snow fall within very short periods of time due to heavy bands of precipitation that were able to rapidly cool the air through evaporative cooling; thus creating conditions prime for a quick heavy snow.  Other areas, such as the Kansas City metro were able to dodge the initial rounds of precipitation and keep mainly rain falling.  Through Monday night however, additional bands created enough cooling to indeed drop a dusting to an inch of snow through the metro area and several inches across additional areas of northeast Kansas and northwest Missouri.  This cut-off low meandered over the central plains for a few more days, creating cloudy and wet conditions for areas of MO/IA/IL and more surrounding states.  Finally the low pressure system was engulfing enough dry air that it began to weaken and has since been picked up by mid-level flow and taken away from the plains.

A shortwave trough is making its' way across the southern plains today, and will bring the threat of thunderstorms and heavy rains to parts of Texas and the Gulf border states over the weekend.  And another trough will work into the plains bringing a passing cold front by Monday, followed by a few additional waves of energy that may likely create a low pressure system on the eastern plains.  This may once again bring a mix of rain and snow for areas of northern Missouri, Iowa, and Illinois; along with a rain/snow mix and perhaps accumulating snow for parts of Minnesota and Wisconsin for early next week.  Beyond this system some portions of the plains may see some very chilly temperatures for mid-week next week as a trough settles into the northern plains and transverses over the northeast by late next week.

Looking out into the guessing land of the models, we look to be flirting with the potential for a large trough for the first week of December which would bring some cold air and perhaps wintery precipitation to the northern and central plains.  Something to keep an eye on for the start of December...

I have better news than the weather though, this past week in Kansas City while I was down for a job interview I was offered and accepted a job in the Kansas City metro area.  Thus, will be relocating to the area sometime late December!  This will make for a busy few weeks as my family not only are in the process of finding a place to live, but the wife and I are going on our cruise from Nov. 30 - Dec. 5 and thus will even be out of the country!

Sunday, November 15, 2009

Rain & Snow for the Plains

A fairly potent storm system is working its' way onto the central plains and will bring significant chances of rain and even snow to areas.  The large trough that will work onto the plains will become cutoff at 500hPa and thus begin to wander the area for a few days until mid-level flow is able to push it off into the Ohio Valley.  While on the plains this system will be able to use all of the moisture available to produce ample amounts of precipitation.  The heaviest precip amounts through Monday morning should be confined to the areas along the cold front passage in the Mississippi Valley regions.  After which the deformation zone along the low pressure system should begin to produce the highest amounts of precipitation.  Interestingly enough, this system does become cold enough to support frozen precipitation over areas of Kansas, Missouri, Nebraska and Iowa on Monday and Tuesday. 

The potential for snowfall and sleet has prompted some Winter Weather Advisories for portions of KS/NE/MO with 3-6 inches of snow being possible across parts of the region.  Other areas may see at least a dusting of snow, and some slick conditions throughout the day on Monday.  You can see a graphical representation of the thoughts from the Kansas City NWS below:

I am currently in Kansas City, MO where I am completing a job interview and some operational forecast testing, thus this event will be very interesting to forecast as I try to show off my forecasting skills.  Nothing like a good cutoff low, mixed precipitation type storm to test on! 

Tuesday, November 10, 2009

Another Week of Sun!

Although not as warm as the previous week that was full of sunny conditions, this week will continue to have a nice fall feel to it with above normal highs through the remainder of the work week.  Under the clear conditions we'll see highs average in the upper 50s across northern Iowa, near 60 across central Iowa, and into the lower 60s and even mid-60s across the southeast and southwest portions of the state.  These conditions won't be completely ideal as we see some gusty winds of 10-20 mph or greater for both Wednesday and Thursday.  If you can deal with the wind, then this week will be another great one for you to enjoy!

The first trough in the mid-levels will work its' way and settle into the west, leaving the plains with favorable southwest flow to allow the potential for rain showers.  A cold front will move through the northern plains late this week, across the state of Iowa on Friday bringing with it the chance for rain showers.  With the passage of the cold front we will see temperatures drop to near-normal temperatures in the upper 40s to mid 50s across the state over the weekend.  Mostly cloudy to partly cloudy skies will also leave us with a bit less sunshine through the weekend...

Beyond the weekend we are looking at the potential for a strong storm system to work its' way onto the plains as the deep trough in the west moves onto the plains and has the potential to become a cutoff low.  This system has the potential to bring some hefty rains, and perhaps some frozen precipitation along the lows path as it moves across the central plains.  More information on this storm system as the week continues and models hopefully begin to come into an agreement.

Friday, November 6, 2009

The Sunshine Continues...

It has been amazing to be able to see the sun for so many consecutive days!  Today will be a bit breezy with southerly winds blowing up warm air at 15-25 mph with some higher gusts possible.  However, temperatures will be pushed up into the 60s and 70s across the state with the aid of this southerly wind.  The cooler temperatures will be confined to the northeast part of the state, where they are a little behind with the temperatures just above the surface.  These temperatures just above the surface will be mixed down today with the aid of those strong winds.  Where the temperatures aloft are cooler, the high temperatures won't be quite as high.  For the portions of western and south-central Iowa, high temperatures in the lower 70s are expected!  The wind will decrease for Saturday, but temperatures will still remain quite nice under the sunshine.  Highs ranging from the mid 60s across a majority of the state, to the upper 60s and near 70 over the southern third.  The latest weather story from the  Des Moines NWS office shows just that, with highs for today and Saturday depicted across the state:

Another sunny day, but once again slightly cooler, will remain for Sunday.  Followed by a chance of showers as a weak cool front blows through the state on Sunday night.  We'll rebound pretty good with sunny skies for a majority of next week, but high temperatures will likely be held in the 50s and lows in the 30s.

Wednesday, November 4, 2009

Enjoy the Day! - New Blog Feature

You can't ask for too much more from a early November day across the state of Iowa.  Temperatures are ranging from the upper 40s to the upper 50s across much of western and central Iowa; with the 40s across the eastern third due to some lingering cloud cover.  We'll likely see a few more days just like this, and likely even warmer, across the state through the remainder of the week.  Clear and sunny skies will give way to temperatures in the 50s and 60s through Saturday this week before our next storm system begins to move in for early next week.  Be sure to get out and enjoy the true fall weather, as October seemed to skip that part.

You'll also notice a new feature on the blog, Twitter Updates!  I recently joined the Twitter world in order to provide a few updates in between blog posts.  This may especially be useful for quick and short updates while on a storm chase, or for general updates on situations.  I'll be sure to note to watch for twitter updates on such occasions, or just be sure to follow me on my twitter page.

Tuesday, November 3, 2009

Light Rainfall

A band of light rain continues to work across portions of western Minnesota and western Iowa, stretching from just northwest of Des Moines, IA to near Fargo, ND.  Typical rainfall values from this line have been less than a tenth of an inch, with only a few isolated spots showing up with greater amounts across southwest Minnesota.  This band of rainfall is occurring ahead of a weak warm front that is working eastward in association with a low pressure system that is located over North Dakota.  Expect this light rainfall to continue to work eastward across portions of Minnesota and Iowa through the evening hours.  Accumulations should continue to be light with only a few hundredths of an inch of rain expected as the rain lasts for only a few hours at most.

Latest Upper Mississippi Radar Image

Sunday, November 1, 2009

A 'Normal' Start to November

After a top ten coldest and wettest month of October across the state of Iowa, and likely so for nearby areas as well, we look to start off the first full week of November in a fairly 'normal' fashion.  Temperatures look to be near normal, likely a few degrees below; and precipitation looks to be intermittent and with total accumulations of a few tenths at most during each of the events.  This sounds much better to those who are wanting to enjoy a little bit of the fall season and is especially helpful for the farmers still wanting to get into the field to complete their harvesting.  Unfortunately, the ground is very wet from the past weeks of rain, and will likely still take several days of dry and sunny weather to dry out the crop.  With light rains potentially in the forecast for this week, we may see the harvesting continue to be delayed by a wet crop.

High temperatures through the week look to range from the lower to upper 50s from roughly north to south on Monday, which will likely be the warmest day of the week.  Continued temperatures ranging from the lower 50s to mid 50s from northeast to southwest across the state through the remainder of the week.  A few locations in northeast Iowa may only see the highs in the upper 40s, as they will remain the cool spot as the upper level trough is steady across the Great Lakes and northeast regions.  Low temperatures will vary a little more, with upper 20s to mid 30s on Monday night from northeast to southwest.  Lower to upper 30s from north to south can be expected on Tuesday and Wednesday night; with a degree or two drop for Thursday and Friday nights' lows.

Precipitation chances enter the forecast due to the passing of two shortwaves that ride the flow across the northern plains on Tuesday and Thursday.  Tuesday's precipitation chances are best throughout the day across the state, higher in the west during the morning hours and in the east during the evening.  Total accumulations expected between a few hundredths to a couple of tenths at most for Tuesday's system.  Thursday's precipitation chances are best during the afternoon and evening hours across the state, with total accumulations of up to a quarter-inch possible.  This is a generalized pattern over the state of Iowa for the week, so you can expect some portions to miss out on these small rainfalls while others may receive the brunt of both systems.

Looking out beyond this week, models are beginning to indicate another large trough to work its' way onto the plains for the time frame of Nov. 9-11.  Precipitation chances are very hard to nail down at this point, and temperatures may see a small window of above normal before likely falling below normal for the remainder of the week (Nov. 12-14) across much of the northern plains.  More details on that system in later updates...