textproduct: Duluth

KEY MESSAGES

- Clipper system for Tuesday will bring widespread snow chances to most of the Northland. A Winter Storm Warning has been issued for southern Lake County with Winter Weather Advisories for the rest of the Arrowhead

- Cooler temperatures persist today. Wind chills ten to twenty below this morning.

- Temperatures gradually increase midweek through Friday with the high temps for Friday in the 40s.

DISCUSSION

Issued at 322 AM CST Mon Feb 23 2026

Current Conditions/Today:

Surface high pressure is moving over the region today with bitterly cold air overhead this morning. Cloud cover from lingering lake effect process can still be seen filtering over NW WI. But the rest of our area is largely cloud free which has lead to some rapid radiational cooling. Morning lows are around -5F with wind chills in the -10F. The exception to this is NW WI where northerly winds streaming over Lake Superior have engulfed the area in stratus providing a warm blanket of temps in the teens.

Dry air in the low levels will be moving in across Lake Superior today and we will see a shift into more southerly winds this afternoon as the air mass departs. The snow showers on the South Shore will taper off but we could still see a lake effect band form in western Lake Superior. A few of the high res guidance is picking up on this convergent band and tries to bring it to the North Shore in the late afternoon.

Clipper Tonight-Tuesday:

A compact low pressure system is set to eject out of the Canadian Prairies and through the Northland Tuesday. Prior to its arrival we will see southerly winds increase with isentropic forcing for ascent ramping up overnight. Dry air in the lower levels will have to saturate out before the snow starts to fly but the North Shore may see an earlier onset time then the rest of the region thanks to the added boost of terrain enhancement. Tuesday morning will be when the best synoptic forcing arrives with the divergent sector of an upper level jet overhead coupled with ample PVA. This will be when we see our heaviest snowfall across the region with rates between 0.5" to 1" per hour. Thermal profiles highlight favorable omega within the DGZ but does have a layer of supercooled water that the dendrites will have to fall through before making it to the surface. The good news is that this profile is not nearly as bad as our last winter storm which produced the wet and heavy snow, this will be more of the usual snow for this time of year. Totals have ticked up just a smidge and we have opted to issued a Winter Storm Warning for Southern Cook County and Winter Weather Advisories for inland Cook/Lake and southern Lake counties. Central and northern St. Louis may need to be put into an Advisory as well depending on how the forecast trends, but at this time confidence is not high enough to add them.

The system moves through at a fairly quick pace with the main band of snowfall exiting to the east in the afternoon. The cold front trailing behind the clipper looks to pack some decent advection with it as it plows through the Northland. Gusty winds will filter in and our low level lapse rates become quite steep with the passage. If we have enough moisture loitering about we could get some more convectively driven snow showers on the backside before all activity wanes in the overnight hours. As mentioned above the lion's share of the snow will be across the Arrowhead and the North Shore with diminishing amounts as you head southwest.

The Rest of the work week:

Surface high pressure fills in for Wednesday with cooler temperatures in play once again. Highs will be in the teens but will mark the start of our warming trend to round out the work week. Temperatures will continue to climb with highs topping off in the 40s for Friday. Precipitation chances continue to oscillate as models waffle with the placement of synoptic features in the extended. There remains good agreement in a low pressure moving across the Central Plains Wednesday with its associated precipitation shield staying to our south or just barely brushing our southern tier counties. Thursday will see the surface high pressure shunted off to the east with increased warm air advection. Weak isentropic ascent could generate some precipitation as a warm front moves through Thursday. But for now we have PoPs less then 15% across the region.

Friday there is good agreement between both the GEFS and the EPS of taking a low pressure system across Manitoba and through Ontario. This will help to draw those warmer temperatures in for Friday. The latest 00Z suite of deterministic guidance favors keeping the bulk of the precipitation north of the border with only a 20% chance of snow for northern MN. As the system slides east a cold front will rush down from Canada and bring our temperatures back down into the teens and twenties to start the weekend.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 531 AM CST Mon Feb 23 2026

Largely VFR conditions across the Northland with mostly clear skies. Northerly wind across Lake Superior are still producing MVFR ceilings which are impacting HYR. Winds will begin to shift to out of the south today and there is growing agreement amongst the models with bringing the stratus over NW WI up into the Twin Ports impacting DLH. Cloud cover across the region will continue to increase out ahead of an approaching clipper set to move in late tonight and through tomorrow.

MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/

Issued at 322 AM CST Mon Feb 23 2026

Northerly winds will be tapering off through the morning hours with marine headlines dropping off. A few of the high res models are hinting at a convergent band of snow developing in western Lake Superior this afternoon and possibly gliding up the North Shore this evening. On Tuesday, a robust clipper system will move through the Northland providing widespread snow. This system will bring with it gusty winds out of the south that will veer to out of the west in the afternoon with the passage of a cold front. Small Craft Advisories will likely be needed for all the near shore waters. Gales are also not out of the question with 40-60% chance along the North Shore.

For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt.

DLH WATCHES/WARNINGS/ADVISORIES

MN...Winter Weather Advisory from midnight tonight to 3 PM CST Tuesday for MNZ012-020. Winter Storm Warning from midnight tonight to 3 PM CST Tuesday for MNZ021. WI...None. MARINE...Small Craft Advisory until 8 AM CST this morning for LSZ140. Winter Weather Advisory from midnight tonight to 3 PM CST Tuesday for LSZ142. Small Craft Advisory until 6 AM CST early this morning for LSZ148-150. Heavy Freezing Spray Warning until 6 AM CST early this morning for LSZ150.