Good afternoon everyone and thanks for checking out the latest Midwest Extreme Wx Update! Overall the short-term is looking rather inactive with light snows lifting through the Great Lakes region tonight. Fast-forwarding ahead to Sunday, our late weekend storm system has had some notable weakening trends and shifts to the south when compared to yesterday’s model runs. The reason why models have shifted our system slightly south and weaker is in part do to the evolution of an East Coast storm system during the day Saturday. Shown below is a trend loop for the East Coast storm system which has shifted northward and stronger over the last 24-36 hours. This will subsequently allow for the upper-level trough to the west (positioned over the central/eastern US) to dig southward and force our wave to be more progressive, meaning weaker and further south. If these northward jogs continue with Saturday’s system off the East Coast, this would allow for additional southward ticks in the Sunday system here.
GFS Parallel model simulation from Saturday night through Sunday night: Watch for our wave to lift out of the Rockies and glide through the southern half of the Central Plains Saturday night through the daytime hours Sunday, likely bringing the heaviest amounts of snow accumulations to KS and MO. The snows will quickly pull into the Ohio Valley, especially locations along and south of I-70 late Saturday night but more so during the daytime Sunday. Model guidance is keen on weakening the system further across the Ohio Valley, which is likely a result of a transfer of energy from the Deep South towards the East Coast, leaving somewhat of a “snow hole” particularly over IN. Regardless, accumulating snow is likely especially along and south of I-70 across IL/IN/OH before the wave quickly works out of the region into the northeast Sunday night.
Here’s a look at potential snowfall with our incoming wave late Saturday night but particularly Sunday: Notice the “snow hole” or lesser amounts in place across IN as that transfer of energy occurs towards the East Coast. This is actually a typical phenomenon for the Ohio Valley as low pressure centers like to ride tighter thermal gradients, which are most common along the East Coast. The further north you head, especially towards the Great Lakes, the less likely snow will become as these parts remain too far north of the main forcing mechanism.
After this wave passes through the area Sunday, we’ll watch for quickly dropping temperatures Sunday night and come Monday morning, areas west of I-69 will likely have wind chill values falling below 0ºF. Definitely not what you would expect for an opening to Meteorological Spring. Check out the wind chills in northwestern IL into IA! -20ºF wind chills are definitely not something to mess around with as this is what you would expect at times during the heart of winter.
Speaking of winter…it is most definitely going to feel like January through next week as temperature departures (shown below) will wind up ending far below typical early March standards. Through the course of the upcoming week, expect temperature departures to end up on average 15ºF below normal in the Ohio Valley as winter hangs on for dear life. Light is definitely at the end of the tunnel as winter is on its tail-end at this point in time and we start looking towards spring and increased severe weather potential during the latter portions of March but especially into April.
Have a great weekend!