PING PONG FOR EVERYONE...
A clipper came flying through the area Tuesday afternoon delivering up to an inch of snow in the far northeast. The rest of the area saw a dusting to 1/2" with nothing at all in the far south where only patchy flurries were found. The big story was the strong winds that coincided with the passage of the upper level short wave. Gusts in much of my area reached 40-45 mph and where snow showers and loose snow was kicked around visibility was a problem for a couple of hours until winds began to subside. Here's some of the 10 meter gusts at 6:00pm.
Temperatures which surged into the low 30s ahead of the disturbance quickly crashed as the short wave passed. By mid-evening readings in my northern counties were well into the teens.
Wind chills of zero to 15 degrees ( -5 to -10 near the Minnesota border) were surging southward.
PING PONG ANYONE?
With all that behind us we start Wednesday nice and fresh with readings in the range of 0-10 degrees. However, the winds have really eased up as a weak ridge passes overhead. That won't last long as the winds rev up again this afternoon due to a clipper that passes well to the north. Gusts of 35 mph possible but coming from the SW they will allow temperatures get out of the hole. By evening all areas should be well into the 30s (above freezing) with some 40s possible, especially south of I-80.
The next volley comes at us Thursday, especially Thursday night when the second of two cold fronts crosses the area. Do you see the trend here, were playing ping pong with air masses. Pressures are going significantly up and down in short periods resulting in a windy pattern that also brings regular fluctuations in temperature.
This front Thursday night contains some Arctic air and when it hits it will deliver a shot of wind and a cold day Friday with near steady or even falling temperatures in the low to mid teens. Wind chills are likely to be in the range of zero to 10 degrees for a very raw day.
Friday night the high pressure executing the polar deposit will be directly overhead killing the winds and allowing for strong radiational cooling, especially in those areas with several inches of snow on the ground. The coldest night of winter so far is anticipated with lows near and north of I-80 5 to 10 below zero.
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A COMPLEX SCENARIO THIS WEEKEND
Then we get into a complicated mess with a couple disturbances ejecting out of a southwestern trough Saturday night through Monday. Models have not been on the same page with solutions the past 24 hours but the latest trends bring a couple shots at snow with some mix still possible in the south, especially near and south of I-80.
The first short wave appears to produce its best lift in the north half where a 1-2" snow potential is indicated Saturday night early Sunday. The EURO is further north keeping the higher 3" totals up near and north of the Minnesota border.
The GFS brings the 3" line close to or just north of HWY 30. I would tend to lean more towards the EURO at this distance and suspect it is handling the overall forcing better. If nothing else, a compromise of the two would be a reasonable starter.
Just for kicks this is what the Canadian GEM indicates.
Things really get off the rails later Sunday and Monday as the EURO and GFS vary significantly on the handling and phasing of the next chunk of energy coming out of the trough. The EURO and Canadian take a second wave further south that brings another round of snow to roughly the southern half of my area. The GFS keeps all the energy bundled in the first wave and shows nothing! I have my doubts about that and again at this early stage will side more with the EURO and GEM and a second separate wave of snow later Sunday/Sunday night. For now, low confidence exists with what happens here. Plenty of time to get a handle on this aspect of the weekend. Meantime, here's what the models are showing for now to give you an idea of what's on the table.
The Canadian GEM
With that, I reluctantly sign off with plenty of doubt about how this all plays out. I'm hoping the puzzle comes together in my next post. Until then, Roll weather...TS