A CHILLING BLOW...
SANTA'S SECRET 5-STAR STOP....
WIND, COLD, AND SNOWFLAKES AHEAD...
A storm system we've been focused on for over a week, has been on a steady track northeast. The center of the disturbance now over Minnesota, is headed for International Falls. From there, it gets absorbed into a deepening upper air low that reforms further east in Michigan. The deeper moisture that was in place Monday has been eliminated, and drier air is set to surge across the region Tuesday. While clouds will remain a factor, precipitation will be confined to isolated showers or sprinkles of little consequence. Winds will remain strong and temperatures, that start mild well into the 50s, will remain steady or slowly fall in the afternoon. This concludes phase 1 of the storm.
By the way, Monday's track of the nearly stacked surface and upper air low into NW Iowa, allowed the heavier precipitation to remain west of my local area. Even so, amounts were still generous, especially west of the Mississippi in eastern Iowa, where amounts were in the 1/2 to 1 inch range. The storm's precipitation shield was significant, covering an area that extended from Texas all the way to Minnesota and Wisconsin, where rain and snow is still falling early Tuesday.
PHASE 2, (SNOWFLAKES FOR SOME)
Tuesday night, the remnants of Monday's energy combines with another bout of vorticity, entering the storm. This pulls the cold core center over Minnesota southeast, where it spawns a new surface low in Michigan. A tight cyclonic circulation will bring windy conditions the remainder of the week. Wrap around moisture spins back into the area and combines with a pocket of cold air aloft to bring the threat of snow showers later Wednesday and Wednesday night. This is phase 2 of the storm.
Temperatures will be in the upper 30s to low 40s before the precipitation begins, so some rain or a mix is initially possible. However, with temperatures at 850 -7 to -9 C., dynamic cooling will quickly cool the column and allow snowflakes to reach the ground. That also allows a rapid drop in temperatures that will have readings in the low to mid 30s come Wednesday evening. Wind chills could reach the low to mid 20s.
The best snow chances are going to be across the N/NE but with very warm ground conditions and only minimal amounts of snow anticipated, not much more than a dusting is expected, mainly on grassy and elevated surfaces. It's possible that a few squalls could develop that bring 1/2 to an inch of snow in isolated spots. Currently, that is the worst case scenario.
One area that could do better is NE Illinois and eastern Wisconsin, closer to the developing low in Michigan. Models are indicating several inches of wet snow there, including such places as Green Bay, Milwaukee, Chicago, and perhaps even Champaign. Last week this was shown further west, but a track slightly further east should spare my area. Very close, but no cigar as it looks now. Here's what models are suggesting for snow totals late Wednesday through Thursday night. Keep in mind a lot of this will be melting and settling, thus accumulations are likely to be lower than the liquid equivalents that are shown in a 10:1 ratio.
The EURO
The GFS
The GEM
The HRRR (only out 48 hours through 6:00pm Wednesday evening)
The last of the snow showers should be east of my area by Friday, leaving us with a dry but chilly weekend. Here's the 15 day meteogram off the GFS for Davenport. It appears the 60s we enjoyed Monday and very early Tuesday are not in our future for some time. The transition to winter, while slow, seems to be underway.
I think the bottom line to this post is that the party is over for the lovely fall weather we've enjoyed for the last 2.5 months. We did mighty well to make it this far! No regrets! Roll weather...TS
