textproduct: Duluth

KEY MESSAGES

- Winter storm affects portions of the area today into early Monday morning. Latest trends have decreased snowfall amounts for northern Minnesota, with resulting headline changes for most of our NE MN counties.

- Snowfall begins through this morning into early afternoon, with peak rates late this afternoon through the evening. The heaviest snowfall amounts are expected for Pine County and across Northwest Wisconsin. There remains significant uncertainty for snow totals from the Brainerd Lakes to the Twin Ports.

- Strong north-northwest winds with gusts of 30-60 mph will lead to blowing and drifting snow. Blizzard conditions are expected along portions of the South Shore, and localized intermittent whiteouts are possible wherever new snow is falling this evening.

- Much colder temperatures are expected into the week with a chance for some light snow accumulations Tuesday.

DISCUSSION

Issued at 421 AM CST Sun Dec 28 2025

We're enjoying the calm before the storm early this morning, though small dewpoint depressions and little air movement yet mean that some low clouds and areas of mist and fog are still around. Generally, the widespread dense fog has lessened but it's unlikely that we'll see completely full visibility before precipitation starts through today.

Today's weather maker is on track, with a slowly strengthening low pressure center chugging across Kansas through this night shift, which at the time of writing had just seen its central pressure drop under 1000mb. Models are in very good agreement regarding the track of the system, moving northeast from its current position across northern Illinois and into the lower peninsula of Michigan - reaching a central pressure in the low 980s by the time it's crossing Lake Huron early tomorrow morning. This track and rapid deepening is still expected to lend itself to some impressive synoptics and winter weather, though there have been some mesoscale adjustments with the latest forecast package:

- The 00z suite of guidance continued a trend we saw in some models yesterday, bringing more mid level dry air across northern MN, and leading to a much sharper northern snowfall gradient. This has led to forecasted snowfall amounts along and north of the Iron Range to fall short of an inch, and Winter Weather Advisories across the Borderlands, Iron Range, and portions of the MN Arrowhead have been cancelled.

- These most recent trends bring the greatest uncertainty to the potential swath of snow that may fall from the Brainerd Lakes to the Twin Ports. Using Duluth as an example, there's some guidance that gives the city a dusting while other models give us as much as 11" - this kind of spread exists across the aforementioned high uncertainty area, including partially up the North Shore as well. With this update, we have opted to downgrade those areas from a Winter Storm Warning to a Winter Weather Advisory, since most 00z guidance did continue to display a downward trend and our forecast is towards the high end of guidance. There does exist a reality where some or all of these advisories would have to be re-upgraded to a warning should near-term model trends and mesoanalysis suggest it, but we've tried our best to follow the full suite of models and a couple personal gut checks with this headline decision. If a re- upgrade were to occur, it would be most likely for southern Aitkin and the Carlton/South St. Louis zones.

- For Pine county and across NW WI, the forecast has stayed much more steady. There are still some large variations in snowfall amounts due to a question of just how high snowfall rates will be and the placement of the best mesoscale forcing, but overall the floor for lowest possible amounts is much higher here. Generally expecting at least 6-12", with higher amounts of 10-20" for the South Shore lake effect belts. Snowfall rates in excess of 1"/hour are likely through this evening across all of NW WI, and some of those higher rates should linger along the South Shore into early Monday morning, especially in the higher terrain of Ashland and Iron counties.

With the rapidly deepening low, strong north-northwest winds are still on track to sweep across the area through the day, reaching their peak through this evening with gusts of 30-60mph, strongest along the North Shore. For the North Shore, have kept the Wind Advisory and High Wind Warning that the day shift issued, to highlight that threat of 50-60mph wind gusts, which extends beyond the end time of the Winter Weather Advisories in effect there. Wind gusts of 35+mph will combine with heavy snowfall rates along portions of the South Shore to lead to blizzard conditions for Ashland and Iron County. It seems likely that much of the rest of NW WI and Pine County will probably experience some brief, localized whiteouts this evening as the best rates and wind gusts overlap, but these conditions are not expected to be as persistent nor widespread as they will be where the Blizzard Warning is in effect.

Outside of the changes outlined above, there have been some minor headline timing changes made to account for most models showing this storm departing the area slightly earlier than what previous forecasts expected. By the time the sun rises tomorrow morning most snow should be over outside of the South Shore, with only some lingering blustery winds that could still be causing some areas of blowing and drifting snow.

Another quick clipper is still expected to zoom over the area Tuesday, bringing some quick accumulations of an inch or less to most of the Northland. Between today's storm and Tuesday's clipper, we should see an efficient push a colder air into the area through the week, with most days seeing high temperatures in the teens or colder and overnight lows below zero. Global ensembles suggest a continued on/off chances for more snow through the new year. CPC outlooks continue to suggest a slight (20-40%) chance for a risk of heavy snow through the first weekend of January.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 532 AM CST Sun Dec 28 2025

Mix of conditions early this morning should deteriorate for most terminals through this morning and early afternoon as snow moves in. Places along and north of the Iron Range (HIB, INL) should see slightly better visibilities with less snow expected. The heaviest snow is expected for BRD, DLH, and HYR. There is some uncertainty on just how much snow DLH and HIB may observe. Strong north to northwest winds pick up through this morning as well, gusting 20- 30knots by Sunday afternoon. Snow and blowing snow may contribute to visibility reductions. Snow continues through the evening. Conditions should gradually return to VFR through Monday morning.

MARINE

Issued at 421 AM CST Sun Dec 28 2025

Strong north-northwest winds ramp up through the day today, with gusts of 35 to 50 knots expected this evening, strongest along the North Shore. Most areas have Gale Warnings in effect, with a Storm Warning in effect from Grand Marais to Grand Portage. A couple localized storm force gusts will be possible from Silver Bay to Grand Marais, but are not expected to be as widespread and persistent as further up the shore. Precipitation is expected to move across the lake through this afternoon, with rain at first that should quickly turn to all snow, heavy at times, which could reduce visibility. Temperatures drop into Monday which will likely lead to heavy freezing spray, especially along the South Shore. Lake effect snow continues through the day Monday which could lead to bands of reduced visibility along the South 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 3 PM this afternoon to 3 AM CST Monday for MNZ020-021. Wind Advisory from 9 PM this evening to 3 PM CST Monday for MNZ020. High Wind Warning from 9 PM this evening to 3 PM CST Monday for MNZ021. Winter Weather Advisory from 9 AM this morning to 3 AM CST Monday for MNZ025-033>037. Winter Storm Warning from 9 AM this morning to 3 AM CST Monday for MNZ038. WI...Winter Storm Warning from 9 AM this morning to 3 AM CST Monday for WIZ006-007. Dense Fog Advisory until 6 AM CST early this morning for WIZ001-002. Winter Storm Warning from noon today to 6 AM CST Monday for WIZ001-002. Blizzard Warning from noon today to noon CST Monday for WIZ003- 004. Winter Storm Warning from noon today to 9 AM CST Monday for WIZ008-009. MARINE...Gale Warning from 6 PM this evening to 9 PM CST Monday for LSZ121-141>148-150. Storm Warning from 6 PM this evening to 9 PM CST Monday for LSZ140. Heavy Freezing Spray Warning from 9 PM this evening to 9 PM CST Monday for LSZ140-145>148-150. Winter Weather Advisory from 3 PM this afternoon to 3 AM CST Monday for LSZ142. Wind Advisory from 9 PM this evening to 3 PM CST Monday for LSZ142.