####018004571#### FXUS63 KFGF 131539 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 939 AM CST Sat Dec 13 2025 .KEY MESSAGES... - Dangerously cold wind chills continue today through Sunday. && .UPDATE... Issued at 938 AM CST Sat Dec 13 2025 A very cold morning across the FA, with wind chills as cold as 53 below zero in the Langdon area. Wind chills have recovered very little, with -40 values as far south as the Highway 200 corridor. With wind chill values that low, headlines remain in good shape as of mid morning. The center of high pressure responsible for the cold will approach the western FA today, which will keep temperatures subzero through the afternoon. This will set the stage for another very cold night. With the center of high pressure much closer, winds should be lighter compared to what we saw last night, keeping wind chills slightly higher. Not that it will matter much, as however you look at it, the next 24 hours are going to be very cold. UPDATE Issued at 549 AM CST Sat Dec 13 2025 Cold and quiet conditions continue with only a few lingering clouds in our southwestern counties. Much of the extreme cold warning is below -40 or close to it. No changes planned for headlines. && .DISCUSSION... Issued at 308 AM CST Sat Dec 13 2025 ...Synopsis... Reinforcing shortwave coming down the backside of the upper low near the Great Lakes will bring more Arctic air over the region today. The surface high will begin to shift slightly south and east tonight, but the cold dome will remain firmly in place. Upper ridging starts building into the Rockies tomorrow, but the south winds and warm air advection won't have an impact until fairly late in the day. Change really kicks in early next week as northwesterly flow becomes more zonal and surface low moving through southern Canada brings westerly wind behind it. Exact highs will be dependent on what happens with stratus and fog as warm air comes over the snow pack, but ensemble probabilities of getting above 32 degrees Tuesday and Wednesday are 90 to 100 percent. Flow starts to become more southwesterly Wednesday ahead of the next trough coming through on Thursday. There are some hints in the ensembles of a fairly impactful system moving quickly through, but a lot of uncertainty not just in the track of the system and snow amounts, but how the warm temperatures on previous days will impact how much snow blows. Does look like we will get another surge of cold air for the end of the week behind the system, although not as bitter as current air mass. ...Extreme cold this weekend... Wind chills currently in the -40 to -45 range across portions of the Devils Lake Basin into the northern Red River Valley. See little reason to make changes to the extreme cold warning at this point. Southern portions of the CWA have more cloud cover and are above -30 in some places, but still plenty cold and will see a continued drop in the next few hours. HREF has high probabilities of -30 or less apparent temperatures continuing through the rest of today and into tomorrow night. Should see some improvement during the day on Sunday. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 549 AM CST Sat Dec 13 2025 VFR conditions with mostly clear skies. Some of the model solutions bring some low stratus into the MN airports later today and into the tonight, but confidence is not high enough to include in the TAFs at this point other than a scattered deck. Winds out of the northwest will increase a bit today, with gusts up to 20 kts at times. Winds will decrease again this evening, eventually becoming light and variable as they start to shift around to the south. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Extreme Cold Warning until noon CST today for NDZ006>008-015- 016-026-027-054. Cold Weather Advisory until noon CST Sunday for NDZ006>008-015- 016-026-027-054. Cold Weather Advisory until noon CST Sunday for NDZ014-024- 028>030-038-039-049-052-053. MN...Extreme Cold Warning until noon CST today for MNZ001-004-005- 007>009-013>017-022>024. Cold Weather Advisory until noon CST Sunday for MNZ001-004-005- 007>009-013>017-022>024. Cold Weather Advisory until noon CST Sunday for MNZ002-003-006- 027>032-040. && $$ UPDATE...Rafferty/JR DISCUSSION...JR AVIATION...JR