IT'S SHOWTIME FOR THE WINTER STORM...
The big winter storm is on the move and is set to arrive by mid-afternoon in the south and evening in the north. The satellite shows the extensive cloud shield and moisture draw from the Gulf. Radar is just beginning to detect snow developing in my southern counties just north of the Missouri border moving slowly but steadily north.
Winter storm warnings extend all the way from HWY 20 in the north to the Missouri border in the south.
The latest trends are fairly consistent with what we saw evolving yesterday with regards to snowfall and that is amounts lowering from west to east as the system slowly weakens as it moves in that direction. The highest amounts are expected to be found from I-380 west towards Des Moines where 6 to potentially 10" totals are possible. Lighter amounts are anticipated southeast of a line from Burlington and Galesburg to near Princeton, Illinois where some sleet and freezing rain is also a threat. Below is the official NWS forecast at this time.
The brunt of the heavy accumulating snow will occur tonight although lighter snow will continue into at least Tuesday morning. As you can see moderate impacts are anticipated around the area according to the latest Winter Storm Severity Index.
New model data has been coming in showing the latest snowfall guidance from this mornings runs. I will show you the range that is helping guide the overall forecast and guidance. You can see there are still some differences between them even at this late hour with totals from location to location. We are looking for consistency so a blend of the raw output is usually a reliable indicator of how much snow will fall. One thing that is clearly evident is the trend for the heaviest snow to fall in Iowa.
The Canadian GEM
The 12K NAM
The NAM 3K
That's where things stand now with the storm knocking on the door. I will be back with you with updates and developing trends as the system unfolds this afternoon and night. Roll weather and white gold...TS
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