175 FXUS63 KFGF 310533 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1133 PM CST Tue Dec 30 2025 .KEY MESSAGES... - A wintry mix of freezing drizzle and light snow may impact travel conditions through 3AM tonight. - Bands of light snow will quickly traverse through the region tonight into Wednesday morning. Light accumulations up to 2 inches may still bring sub-advisory type impacts to the early morning commute. && .UPDATE... Issued at 1133 PM CST Tue Dec 30 2025 As colder air aloft arrives and saturation deepens, we are seeing a transition from freezing drizzle to snow in the Devils Lake Basin into the northern Red River Valley. Drizzle has become a more consistent flurry here at the office, with higher radar returns upstream soon to arrive. Further south and east, freezing drizzle continues, especially from the central Red River Valley into west central MN. Updated grids to reflect these latest trends, with the winter weather advisory still on track to expire at 3AM, as by then we should be over to predominately snow across the entire FA. UPDATE Issued at 902 PM CST Tue Dec 30 2025 Webcam images and surface observations show mist/freezing drizzle/light snow over much of northeastern ND and northwestern MN. This wintry mix has been on full display at the office, alternating between flurries, drizzle and nothing. Until deeper saturation and better forcing arrives with our next weak clipper that is still up in Canada, this wintry mixture will likely continue. Therefore, a winter weather advisory has been issued for much of the FA until 3AM to cover the icing threat. After midnight we should see a transition to more predominate snow, with freezing drizzle ending by 3AM. UPDATE Issued at 612 PM CST Tue Dec 30 2025 A complicated evening, with light snow, drizzle/freezing drizzle and fog all keeping things busy in the short term. Compared to earlier today, visibilities have improved, which would seem to indicate freezing drizzle has decreased in coverage. However, in the past hour or so several sites have started to see visibility decrease again. Stepping outside here at the office a bit ago, there was a very fine mist falling, but now it seems to of ended. To keep things simple, I added in more drizzle through midnight. As the backdoor cold front continues to sag south and west, high res model guidance depicts fog developing in southeastern ND later tonight. I did not add it in at this time, as this could turn into more of a drizzle then a fog anyways. However this will need to monitored over the next several hours to see if any changes are needed. && .DISCUSSION... Issued at 121 PM CST Tue Dec 30 2025 ...Synopsis... General upper ridging into the western CONUS and upper troughing along the Atlantic Seaboard attached to an upper low over the Hudson Bay places our region generally in northwest flow aloft through the remainder of the work week. This will promote quick moving, weak clipper-type systems across the Northern Plains and Upper Midwest. Each will bring its own brief period of light wintry accumulations, mainly in the form of light snow, with the exception of today's weak clipper which has resulted in freezing drizzle. This will also promote generally below average temperatures behind a backdoor-type cold front moving through the area today. After today's above average temperatures in 20s and 30s, highs are forecast to generally be in the single digits to teens above zero, with lows in the single digits to teens below zero. Toward this weekend into early next week, upper ridging in the West will tend to build eastward into the Great Plains. Ensemble guidance varies in how amplified this ridge will be, dictating how warm (or not warm) temperatures will trend. A stronger, more amplified upper ridge would promote average to above average temperatures (including the potential for more above freezing temperatures), along with the periods of light wintry mix including more freezing drizzle/light rain as well as light snow. Weaker/Less amplified ridging would promote temperatures closer to average, with periods of light snow in lieu of wintry mix. There is currently no signal for strong/significant winter precipitation nor high winds within ensemble guidance through next Monday. ...Wintry mix this afternoon into evening... Weak surface low pressure system moving south-southeast through northwest into central Minnesota continues to result in light wintry mix of freezing drizzle and light snow within portions of Minnesota and the northern Red River Valley. Air temperatures on its western flank have warmed above freezing, along with surface temperatures via RWIS observations. This has mitigated any ice impacts generally west of the Red River (with the exception of the far northern Valley). Thus, the Winter Weather Advisory for light ice impacting travel conditions is largely confined to Minnesota through the early afternoon. As the weak surface low departs, a backdoor-type cold front moves through from the north/northeast tonight into Wednesday. This will tend to shunt any residual low level moisture that would feed continuing wintry mix into portions of eastern North Dakota the southern Red River Valley, and west-central Minnesota late afternoon into early evening. Confidence is not high enough in sustained freezing drizzle production to deposit additional glaze of ice in these areas, thus the 3 pm expiration time of the current Winter Weather Advisory seems to be on track as forcing near the surface low departs. However, there is still a 20% chance travel impacts ensue in these aforementioned areas should the backdoor cold front be enough to force sustained freezing drizzle into existence. Thus, there remains a low chance for travel impacts from glaze of ice late this afternoon into early evening within portions of eastern North Dakota, the southern Red River Valley, and west-central Minnesota. While blowing snow was previously messaged to be a potential impact toward travel conditions behind the cold front, vast majority of guidance have come into agreement in winds remaining low enough mitigate this potential impact. Breezy winds will still be able to create minor drifting snow in open country. ...Light snow tonight into Wednesday morning... The next quick moving clipper-type feature to traverse the region comes late tonight into Wednesday morning. Temperatures will be cold enough behind the cold front to keep precipitation type as snow. Synoptic forcing associated with this snow is greatly lacking, if at all existent. Light snow tonight into Wednesday morning will almost be purely mesoscale-driven in the form of transient frontogenesis sliding southeast along the backdoor cold front. This will result in transient, unorganized yet elongated bands of light snow to move quickly across our area. While frontogenesis commonly can lead to 'higher end' snow amounts, this particular scenario is not one of them - mainly due to absence of more organized synoptic forcing and a thermodynamic profile that does promote high SLRs. Additionally, there is a deft in upright instability; however, there will be some slantwise instability available for the frontal circulation to utilize. Thus, there could be some transient burst of higher snow rates over localized areas. Ultimately, snow accumulations from this snow is forecast to be in the half inch to around 2 inch range. With the potential of transient burst of moderate snowfall as well as accumulations between 1 to 2 inches, sub-advisory impacts are possible (50%). This may impact the early morning commute, as even lightly accumulating snow and visibility reductions near half a mile could result in hazardous travel conditions. By sunrise, most snow is expected to have already departed our area into central Minnesota. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1133 PM CST Tue Dec 30 2025 FZDZ transitions to -SN over the next few hours, with visibilities dropping further from MVFR to IFR as this transition occurs. Snow will continue overnight into early Wednesday morning, ending from northwest to southeast mid morning into the afternoon. Ceilings will remain stuck at MVFR/IFR levels through Wednesday morning, then slowly improve. All TAF sites will be back into VFR by the end of the TAF period. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Winter Weather Advisory until 3 AM CST Wednesday for NDZ007- 008-015-016-026-027-029-030-039-053-054. MN...Winter Weather Advisory until 3 AM CST Wednesday for MNZ001>009-013>017-022>024-027>032-040. && $$ UPDATE...Rafferty DISCUSSION...CJ AVIATION...Rafferty