textproduct: Twin Cities

KEY MESSAGES

- Lingering light snow ends from west to east today, with travel impacts through the evening commute.

- Cold temperatures tonight with lows in the single digits across the area.

- Another round of snow expected to arrive midday tomorrow in western MN, spread southeast through early Sunday. Several inches of accumulation are possible in southern MN with lower amounts to the north.

DISCUSSION

Issued at 159 PM CST Fri Dec 5 2025

Radar echoes continue to churn over the eastern half of Minnesota and through western WI this afternoon, with the strongest echoes and highest snowfall rates skirting just to the south of the MPX CWA in WI in portions of Wabasha, Trempealeau, and Buffalo counties as of 130pm. High resolution guidance has not performed particularly well with the evolution of the light snowfall today, as it tends to struggle with high PoP/low QPF type of scenarios. The latest HRRR/RAP show lingering echoes in southern MN through 21-22z after which point all snow tapers off this evening. Additional accumulations in the area should remain rather low, with an additional tenth of an inch or two in areas that continue to see some light snow. Visibility has generally been improving per automated surface observations, generally improving from 2 miles or lower while snow is falling to above 7-8 miles as it ends. In this type of environment, visibility is a decent proxy to snowfall rates, thus once the visibility improves we can generally say that lingering radar echoes are struggling to produce noticeable precipitation. Temperatures are expected to crash behind the departing snowfall as northwesterly winds stack across all layers of the troposphere, allowing overnight low temperatures to range in the single digits above zero tonight with the warmest temps in the metro urban heat island.

Another clipper type snow event is likely tomorrow favoring western to southern Minnesota and into Iowa, beginning around midday in western MN and spreading southeast into the evening before ending early Sunday morning. Guidance is still wobbling, especially the high resolution guidance as there was a significant discontinuity between the 00z runs last night and the 06/12z runs this morning, with the 18z returning to align with the earlier runs. The 06/12z HRRR especially pushed snowfall potential much farther north which has again retreated back to the south with the 18z guidance, as the 18z RAP shows a solid footprint of snow along and south of the Minnesota River with the highest amounts in northern Iowa. From our snow events so far this season, the RRFS/AIFS have acted as a steady anchor point for the forecast as the guidance has trended towards their solutions the closer we have moved towards an event, and no surprise the return to the more southerly solution within the 18z guidance is also following this trend as both keep the axis of highest snowfall potential from roughly Sioux Falls to Des Moines. Dynamics wise this looks to be a quintessential clipper type event with a strengthening mid level shortwave on top of a deep dendritic growth zone due to cold low level temperatures. Forecast soundings show a deepening DGZ as precipitation begins, with dynamic cooling allowing for better saturation and efficient snowfall production into the evening. The vertical continuity between the 925-700mb isodrosotherms and shortwave moving through should produce the heaviest bursts of snowfall as frontogenetic forcing remains aloft with the lack of a defined surface system/boundary, which timing wise favors the late afternoon through evening time frame south of the Minnesota River. With the snowfall relying on the omega from the shortwave, snow should end rather quickly as the forcing departs to the southeast, with most of the area done with snow after midnight. Overall accumulations are still fluctuating based on the expected track of the shortwave, with a solid 3-6 inch range south of the Minnesota River decreasing to 1-2 inches for most of the Twin Cities metro and even lower amounts to the north where the forcing cuts off. The highest overall amounts of 6 inches or more look to fall in central to northern Iowa where the best chance to line up the forcing with the best environment matches up, however there is still enough movement run to run within the guidance that some shifting is still possible. A Winter Weather Advisory has been issued along and south of the Minnesota River, with some upgrades/expansion possible tonight with the midnight shift having fresh data to work with after the 00z upper air soundings. Travel impacts are expected Saturday evening into early Sunday, especially along I-90 where our highest amounts are most likely, with impacts tapering off as crews have time to work on Sunday.

Temperatures remain cold on Sunday in the single digits with lows dropping below zero in spots both Sunday and Monday morning before we warm back up into the 20s on Monday ahead of our next potential system. Guidance late Monday into Tuesday favors a weak surface low developing alongside a diffuse upper level shortwave tracking from Grand Forks down through Duluth, which would place an axis of precipitation along our border with the DLH NWS office. We may be dealing with some p-type issues as we warm up enough to get above at the surface, with 850mb temperatures trending towards the freezing mark as well. There are still a few ways this could play out depending on where the forcing ends up and how far north the warmer air pushes, but don't be surprised if we start to mention a wintry mix of rain, snow, and freezing rain/drizzle on Tuesday next week. Stay tuned for more detail as there is still a high degree of uncertainty depending on how things evolve. Yet another shot of colder air is appearing within the longer range ensemble guidance afterwards, returning us back to our clipper train type environment we have been in since Thanksgiving.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1138 AM CST Fri Dec 5 2025

Snow is gradually coming to an end this afternoon across the area. Some terminals are even rising into VFR, but MVFR will be more likely as snow comes to an end. Some IFR will be seen as snow is still falling, but a quick improvement is expected as it comes to an end. Later in the afternoon into this evening lower MVFR into high IFR ceilings are expected, before VFR becomes more widespread overnight. Another snow system is expected tomorrow, but the heaviest snow is expected to the south of the terminals. RWF and MKT are most likely to see snow and as the forecast starts to come into better focus, more impacts will be added to those TAFs.

KMSP... Light snow will continue for much of the afternoon, but the main accumulation phase has ended. This will be mainly a MVFR visibility impact for the last few hours of this light snow. More snow will arrive across southern Minnesota tomorrow. How far north this snow gets, and therefore impacts to MSP, is still uncertain. With this uncertainty opted to keep the TAF dry, but if the northern solution were to win out the timing of the snow would be in the evening and could impact the later part of the rush period.

/OUTLOOK FOR KMSP/ SUN...Likely VFR. Wind N 5-10 kts. MON...MVFR cigs. Chc -SN. Wind SW 10-15 kts. TUE...VFR early, MVFR/IFR late with -SN. Wind S 10-15 kts.

MPX WATCHES/WARNINGS/ADVISORIES

MN...Winter Weather Advisory from noon Saturday to midnight CST Saturday night for Blue Earth-Brown-Faribault-Freeborn- Martin-Nicollet-Redwood-Steele-Waseca-Watonwan-Yellow Medicine. WI...None.