Monday, December 7, 2009

Winter Storm: Dec. 7/8

A significant winter storm is expected to impact much of the plains states beginning tonight and continuing through Tuesday and into Wednesday.  Winter Storm Warnings have been issued as far west as the NE/KS and Colorado borders to the east and northeast to the upper peninsula of Michigan.  Winter Weather Advisories have been posted for many of the areas adjacent to the warnings, with snow accumulations still up to 6 inches in those areas.  As the low pressure system strengthens during the day on Tuesday and into Tuesday night, expect a significant increase in the winds for portions of IA/MN/WI/IL.  For this reason, a blizzard watch and even blizzard warnings have already been posted where conditions are likely to become favorable for significant snowfall accumulations of 1-2" per hour and wind speeds sustained at greater than 35 mph.

Forecast models continue to be consistent in indicating the heaviest snowfall axis from north-central Kansas into Nebraska, Iowa and Minnesota.  Adjacent areas and areas further northeast will also see significant amounts, however not on the same terms of 10-12" that are possible over those areas of KS/NE/IA/MN.  This storm will be a very strong first winter storm for many, meaning that travel conditions will be very treacherous, and likely will result in travel not being advised for a significant portion of the plains.  It will be important to head these warnings, as conditions will likely deteriorate quickly with strong winds, and wind chills will be well below zero for those that do become stranded.  There will be plenty of coverage by local news stations and even national news stations as this event will cover so much of the plains states.

The latest snowfall forecasts by tonight's (00z) model runs are posted below:

00z 40km NAM

00z 5km WRF

Additional updates are likely tomorrow as the storm begins to affect the plains states, however, updates may be scarce as my location is within the warning area.