A significant winter storm is on our doorstep and will begin to impact all of the region in the coming hours. Low pressure will continue to deepen as it moves northeast out of Oklahoma, Arkansas, and into Kentucky. As this takes place, copious amounts of moisture will lift north into central Indiana. We think precipitation reaches Indianapolis, itself, during the overnight (likely between 3a and 4a).
The bulk of the northern half of the state is still expected to receive predominantly snow with this storm. However, things get much more tricky along the I-70 corridor (10 to 20 miles either side) as temperatures will be “marginal” early on in the event (aloft and at the surface) and will lead to quite the headache for the first several hours of this storm. Even as of this update, confidence is low on precipitation type for the I-70 corridor, itself. A difference of half a degree (F) can mean a world of difference with precipitation type (snow, freezing rain, sleet, or rain). Admittedly, concern is growing for the potential of icing in this area before the deeper cold air can arrive and switch things over to snow. On the other hand, should precipitation rates be heavy enough, it’s certainly possible these heavier rates will cool the entire column of air quicker than high resolution modeling currently suggests and a quicker transition to snow would result. “Boom or bust” potential is higher than normal along the immediate I-70 corridor.
Given the above, and the potential of a “deformation band” of snow to develop during the 2nd half of the storm, our forecast snowfall totals remain unchanged.
Stay tuned and please know we’ll have another update posted Saturday morning.
The other big concern here is the fact that east-northeast winds will turn increasingly strong and gusty as the day gives way to afternoon and evening. Winds may gust as high as 40 to 50 MPH at times during this time period as the storm heads off to the northeast. Even if you accumulate an inch of snow, expect blowing and drifting issues to result. Combine that with rapidly falling temperatures Saturday evening and the stage will be set for slick and hazardous travel throughout the region.
Much more in a few hours around this storm and additional “fun and games” that await next week… (Please send coffee ;-)).
II. As we look ahead, our next weather system will scoot into the region over the weekend. This will be a weak event and we only expect a light mixture of snow and rain Saturday evening.
III. The balance of Thanksgiving week looks rather quiet, but chilly, thanks to high pressure. The stretch of below to well below normal temperatures will continue, overall.
IV. As we look ahead, the pattern sure looks cold and stormy as we open December. On that note, the majority of data continues to trend colder for the month of December, as a whole, and with high latitude blocking in place, we’d expect to see an active storm track across the country. If you like it cold and active for the holidays, you just might be in luck this year… More on that later!