1/21/2012-
The system produced generally just 1 - 3" snowfalls across much of the region. The heavier band of snow ended up falling just south of the region across northern Indiana and Ohio where I saw heavier reports of 5 - 8" as the bulk of the moisture stayed south of our region. Another related problem here was snowflake size which was very small with the very cold air in place prior to the event. My forecast of generally 2 - 4" with areas of 3 - 5" was a bit too aggressive in this Saturday morning quarterbacking review with a 1 - 3" call better suiting the event.
Snowfall reports from NWS White Lake Mi
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Original Post
A quick third shot of Arctic air will plow through Southeast Lower Michigan Thursday. This reinforcing blast of Arctic air will be accompanied by gusty winds, snow showers and flurries. While accumulations of snow will be around an inch or less, falling temperatures and blustery winds will make for an uncomfortable January day for sure.
The better snow maker will move into Southeast Lower Michigan quickly on heels of the Thursday system during the day Friday. Our extended and now short term models have been fairly consistent with this system with its broad area of moisture, good forcing and lift which will squeeze out any available, layered moisture. While the center of the actual low pressure will be far south over the lower Ohio Valley, moisture will be flung far to the north over the Southern Great Lakes. Even though the moisture and precipitation amounts are not high with the system; they will be more than sufficient, given the dynamics of this system, to give much of the region its best snowfall of the season (considering the previous light amounts). I'm generally looking for at least 2 - 4" of snow but with higher areas of 3 - 5" possible in the heaver snow. Even scattered pockets of 6" amounts are not unreasonable given the cold air mass in place and resultant high snow to water ratios of the system. The snow to water equivalent ratios should generally fall in the 15-20 to 1. This means for every .10" of precipitation (or melted water equivalent), snowfall should range in the 1.5" to 2.0" (possibly even as high as 2.5"). There's even a slight risk of some freezing rain near the Ohio border if the warmer moist layer is flung far enough north to clip that region. This system will have to be watched for any type of path change as some of the models are beginning to hint a bit further north with the core moisture. Any updates will be issued if needed in my blog.
Needless to say driving beginning Friday afternoon into Saturday morning will become slippery and dangerous and all cautions should be exercised.
Making weather fun while we all learn,
Bill Deedler - SEMI_WeatherHistorian
