6:14 PM Wednesday, December 21, 2022
- Winter Storm Warnings and Advisories remain in effect for much of the Northland through Saturday.
- An upgrade to a Blizzard Warning is possible for the North Shore and South Shore of Lake Superior for the Thursday night through Saturday time frame.
- Accumulating snow continues area-wide tonight with lingering snow showers and flurries continuing Thursday into Friday over the Arrowhead and North Shore.
- A prolonged period of lake effect/lake enhanced snow for the South Shore in northwest Wisconsin through Saturday.
- North to northwest winds increase on Thursday and get even stronger Thursday night through Saturday with wind gusts of 30 to 45 mph likely, to as strong as 65 mph along the North Shore of Lake Superior.
- High winds could cause power outages due to snow-loaded trees from last week’s storm.
- Visibility reductions with blowing snow Thursday through Saturday.
- Very cold temperatures and wind chills continue through Saturday. Highs in the single digits below to single digits above zero, with lows ranging from the single digits below to around 20 below zero. Wind chills ranging from 25 below to around 40 below zero through Saturday.
Larger view of current winter weather alerts.
WIND CHILL ADVISORY in effect through 12 PM Saturday (light blue area on map)
For Duluth — Snow continues tonight but it should diminish Thursday morning (around 5 AM) but it may end up a little earlier or later since the computer models struggled just a bit on the timing for when the snow would begin today, ended up being quite a bit earlier than expected. Might see a few peeks of sun on Thursday, but a few flurries and snow showers will probably continue as well.
18z NAM 3km model radar forecast through 6 PM Thursday (snow in blue)
No changes made to my snowfall forecast.
Forecast snow totals through 6 PM Saturday.
Note — The bulk of this snow falls tonight into Thursday morning, except over the Arrowhead and North Shore where some snow will continue at times through Friday, and also in the snowbelt region in northwest Wisconsin (South Shore) where snow will likely persist through Saturday.
0.9 inches of snow has fallen thus far in Duluth today (thru 4 PM) with a snowfall ratio of only 7:1, and this is well below what the computer models were showing for this event. The arctic air mass has led to very small snowflakes in Duluth today (takes longer for the snow to pile up when dealing with fine/small snowflakes) and if this trend continues tonight, then we probably won’t see much more than 2 or 3 inches of total snow accumulation in Duluth out of this system.
HIGH WIND POTENTIAL
Strong north to northwest winds will develop in the Northland on Thursday and these strong winds will continue into this weekend.
Currently it looks like the strongest winds in northeast Minnesota and northwest Wisconsin will occur from Thursday evening through Christmas Eve (Saturday), but gusty winds could linger into Christmas Day (Sunday) especially near Lake Superior.
NAM 850mb wind forecast valid from 6 AM Thursday to 6 PM Saturday.
Shown below are forecast winds at 850mb or 5000 feet in the atmosphere, not all of this wind will mix down to the surface, but the fact we’re seeing such strong winds aloft at 50-60+ knots makes me believe will see winds down here at the surface of at least 30 to 40 mph, and likely even stronger than that.
Reds=850mb winds of 50 to 65 knots
Purples=850mb winds of 70 to 80 knots
Wind gusts of 20 to 35 mph will develop in the Northland on Thursday with even stronger winds expected Friday into Saturday with wind gusts of 35 to 45 mph, to as strong as 50 to 65 mph along the North Shore of Lake Superior.
NAM wind gust forecast valid from 6 AM Thursday to 12 AM Sunday.
POWERFUL WINTER STORM DEVELOPING
Strong jet stream winds diving SE across the Rockies combined with a trough digging S/SE across the northern Plains will help fuel a rapidly deepening low-pressure system as it tracks from the Midwest to the eastern Great Lakes by Friday.
Goes-16 water vapor loop from Wednesday, December 21, 2022 (loop time ends 5:50 PM CT)
Upper-Level analysis
TEMPERATURE CONTRAST — SIBERIAN EXPRESS
Incredible temperature gradient over Colorado this afternoon ranging from around 50 in eastern Colorado to around zero in northern Colorado.
Low Temperature Reports from Wednesday morning, December 21, 2022
Source: National Weather Service Duluth, MN
Embarrass, MN: -30 F
2 S Tower, MN: -30 F
Birchdale, MN: -29 F
Ash Lake, MN: -29 F
Effie, MN: -27 F
Orr, MN: -27 F
Northome, MN: -27 F
Cook, MN: -27 F
Bigfork, MN: -26 F
Ely, MN: -26 F
Isabella, MN: -25 F
Cass Lake, MN: -24 F
Eveleth-Virginia, MN: -24 F
Winton, MN: -24 F
Longville, MN: -24 F
Walker, MN: -23 F
Deer River, MN: -22 F
Chisholm, MN: -22 F
Hibbing, MN: -21 F
Brainerd, MN: -20 F
Grand Rapids, MN: -20 F
Solon Springs, WI: -20 F
Butternut, WI: -19 F
4 W Clam Lake, WI: -19 F
Duluth Airport: -18 F
Aitkin, MN: -18 F
Cloquet, MN: -18 F
Hayward, WI: -17 F
Grand Marais Airport: -17 F
Superior Airport: -16 F
Siren, WI: -16 F
Duluth Sky Harbor Airport: -13 F
Thanks for reading!
Tim