/Issued 4:47 PM CST, Monday, February 12, 2018/
20z HRRR model
Wednesday’s thaw is still on track, but it will be brief as colder temperatures return once again later this week.
•15 days in a row with a below zero low temperature at Duluth, Minnesota (January 29-February 12) This is the longest streak of below zero low temperatures so far this winter, the previous longest was 14 days in a row from December 24-January 6.
Cold pattern continues for about the 15th day in a row across the Northland. Lots of sunshine again today but temperatures remained well below normal with highs only in the zero to around 10 above range — Changes are coming, and they will begin Tuesday.
Tonight: It’ll start off kinda chilly as temperatures range from the teens below to single digits above zero, but temperatures are expected to rise a bit by daybreak with locations that drop below zero likely climbing above zero by 7 AM Tuesday. Clear to partly cloudy skies this evening will become mostly cloudy later in the night as a warm air advection pattern develops as winds turn southerly as high pressure heads southeast and out of the upper Midwest. There is also a weak wave that’ll approach from the western High Plains later tonight, and there could be just enough lift/moisture combined with a strengthening SW low level jet of 30 to 50 knots to kick off a little bit of snow in parts of the Northland Tuesday morning.
Tuesday: The aforementioned wave which could bring a dusting of snow to parts of the area late tonight/Tuesday morning will scoot off to the E/NE and away from our area by early afternoon, in its wake expect partly sunny to mostly cloudy skies with milder temperatures with highs in the 20s, lows Tuesday night will be in the teens to around 20 degrees, so a lot warmer compared to the last two weeks.
Note: Wednesday still looks like the warmest day of the week as southwest winds occur out ahead of a southeastward moving cold front while an area of low pressure passes by to our north. 850mb temperatures of -12 to -18C this evening will warm to +3 to +5C Wednesday, and this should result in most of the Northland climbing above the freezing mark with a few spots possibly climbing into the lower 40s Wednesday afternoon. This warmth will be short lived, however, as a cold front swings through the area Wednesday night ushering in chillier temperatures for Thursday and Friday. There could also be some light snow around the area late Wednesday night or Thursday with some locations picking up around an inch of snow at that time.
Forecast for Duluth and Superior
.Tonight… Increasing cloudiness. Light snow or flurries possible mainly after 4 AM. Low 0 to 5 below with slowly rising temperatures overnight. Wind southwest at 5 to 15 mph.
.Tuesday… Light snow or flurries early otherwise partly to mostly cloudy. Total snow accumulations less than one inch. Milder. High 24 to 29. (First above normal high temperature since January 31) Wind southwest at 10 to 20 mph.
.Wednesday… Partly to mostly cloudy. High 35 to 40. Wind southwest at 10 to 20 mph.
Normal temperatures for Tuesday
Sunrise Tuesday: 7:16 AM CST
Sunset Tuesday: 5:31 PM CST