An area of low pressure over northeast Colorado this afternoon will lift northeastward, reaching central portions of Lake Michigan by Wednesday evening — This system will produce some rain across southern portions of the Northland on Wednesday, especially in the afternoon-early evening, but northern Minnesota and the Arrowhead should stay dry on Wednesday. It will also be quite breezy in parts of the Northland on Wednesday, with NE winds gusting 20 to 35 mph especially near Lake Superior.
Our system for Wednesday continues to move across the central Rockies today where it has been and will be producing some snow or a mix of precipitation types in parts of Wyoming, South Dakota and Nebraska through Wednesday morning.
Goes-16 water vapor loop from Tuesday, October 19, 2021.
Note: There are some differences in the computer models on how far north the rain will get on Wednesday with a slight nudge to the north noted between the 12z and 18z model runs today. The latest data as of late this afternoon would bring the northern extent of the rain to about the Highway 2 corridor in northeast Minnesota, and also affecting much of northwest Wisconsin, with a little rain even possible in the Twin Ports. Again the timing of this would be Wednesday afternoon-early evening, with the morning hours of Wednesday looking dry, except near Lake Superior where some patchy drizzle is possible.
18z NAM 3km model simulated radar forecast valid from 7 AM Wednesday to 7 AM Thursday.
The highest rainfall amounts for Wednesday are still expected to setup from south-central to eastern Minnesota to central Wisconsin where widespread half inch to >1″ of rain is possible, but rainfall totals will drop off significantly farther north.
You can really make out where a cold front was located at mid-afternoon today by the temperatures and satellite imagery.
West of the cold front, skies were mostly cloudy with temperatures in the 40s this afternoon, while east of the cold front skies were mainly sunny with temperatures in the upper 60s to lower 70s.
The Duluth Airport hit 70 degrees today, October 19, 2021, and this could very well be the last time we hit 70 in Duluth this year since the average date for last 70 degree temperature in Duluth is October 9, but just last year, Duluth had three days in the 70s in November, one as late as November 6th (75 degrees). For those wondering, the latest date for last 70 degree temperature in Duluth occurred on November 9 (set in 1999).
Today will likely be our last real warm day (compared to normal) at least for a little while.
Temperatures will be cooling off quite a bit over the next few days, with daytime highs in the Northland generally in the 40s to around 50 from Wednesday through Sunday, but our normal highs at this time of the year are mainly in the upper 40s and lower 50s, so yes it will be a lot cooler, but really we’re just heading back to where we should be here in mid October.
Temperatures aloft will be cooling off enough to where we could see some frozen precipitation in the Northland late this week.
850mb temperatures (shown below) are forecast to range from around -2 to -4C on Friday, so if we can get the surface temps to remain cold enough, then we could very well see the season’s first snow flurries especially over the far northern Minnesota (white outlined area on map).