29. Models are still consistent with Monday's low pressure system.
The top screenshot is from the midnight run (0600z) of the GFS computer model at 66 hours... that's 18:00 on Monday (28th).
The bottom screenshot is the one I used in yesterday's blog; I've added it for comparison.
In today's run the model takes the low a little farther south. Yesterday's model shows the low along the US/Canadian border, today's now puts it in east-central Minnesota. The exact latitude, even a little bit, will be important when it comes to which type of precipitation will fall across northern Wisconsin. Between the two model runs, the 540 thickness line has moved a little farther south -- closer to northern Wisconsin.
The 540 thickness line (the first dashed blue line above the dashed red ones) is used as the snow line. It's not exact, but it's a fair estimate of the snow/rain line. North of the 540 thickness line will probably have snow, south of it will see rain, and along it may see something in-between.
From the NWS in Duluth: "INCREASE IN WARM AIR WILL BRING TEMPERATURES NEAR OR ABOVE FREEZING ALONG WITH ATHREAT OF MIXED PRECIPITATION AND FREEZING RAIN."
My forecast here on Maple Hill.
The screenshot (to the left) is from the NWS and shows the next five days: a warm weekend (sunny on Sunday with 34 degrees!) and then the system on Monday. Behind Monday's mess, arctic air returns... we'll have to see how low and for how long.
The Graphical Forecast for Monday at 13:00.
The lavender colors show the areas that may see ICE (freezing rain) during the mid-day hours on Monday. The darker shading indicates where heavier amounts are expected.
At this moment, it looks like northwestern Wisconsin will be having a freezing rain event.
If temperatures rise high enough, the freezing rain may turn briefly over to rain before refreezing later. If the low pressure shifts a little farther south, the cold air will be closer to northern Wisconsin.
The fine details will turn this system one way or the other. I'll be keeping a close eye on this system through the weekend.