FXUS63 KFGF 021457 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 957 AM CDT Sat Nov 2 2024 .KEY MESSAGES... - Rain spreads north Saturday night into Sunday and exits east Sunday night and Monday. A 60 percent chance of an inch or more in some locations. There is a 20 percent chance for thunder Sunday evening near the South Dakota border. && .UPDATE... Issued at 957 AM CDT Sat Nov 2 2024 Pockets of dense fog have become prevalent across portions of the northern Red River Valley with improving conditions expected around noon for the most affected areas. Have issued a short term SPS for the fog in said areas to aid messaging. Otherwise forecast for today remains on track. UPDATE Issued at 649 AM CDT Sat Nov 2 2024 The hole in the clouds is expanding slightly from Cavalier to west of Grand Forks. In this area temps drop a bit and there is some patchy fog. The rest of the forecast area remains in the lower clouds. Per usual 12z time frame, ceilings are lowering and getting a bit more fog (mostly 3-4SM). Webcam views show fog behaving. No changes otherwise, but much uncertainty in regards to cloud trends later today. && .DISCUSSION... Issued at 320 AM CDT Sat Nov 2 2024 ...Synopsis... Western Canada and western U.S. 500 mb trough to start the weekend. Northern short wave is over southern British Columbia and will move northeast and have no impacts on our area. Stronger wave moving southeast and will be at the base of the upper trough over Arizona and New Mexico late Sunday. Ahead of this more southern short wave will be a long feed of moisture (sfc-500 mb) which will spread north the next 24 hours. Next week will see the Arizona short wave move northeast while the western Canadian short wave moves northeast as well. An elongated upper trough will be present, positively tilted, mid week with some light precip chances Tues-Wed. SSW flow aloft will re-establish itself by late week and next weekend with precip chances increasing by next Saturday. ...Today... 500 mb short wave that was in NW SD is in northern MN at 06z. The precip with this wave which was diminishing as forecasted is over NE MN. Net result over eastern and central ND and northwest MN is extensive low level moisture and cloud cover. Near calm winds to start today...will lead to areas of fog in E ND. Though main fog in terms of lower vsbys likely to be tied to any holes of clearing that form or along the west edge of the low cloud deck more in western ND. Will monitor fog, but for now the areas and patchy fog mentioned for RRV and west seem reasonable. Getting into that time of the year when clearing of the lower clouds is getting more questionable. Do think some clearing will take place but full clearing is uncertain. This will have to be monitored for short term aviation trends. ...Tonight-Monday... 850 mb winds of 40kts spread north into the area tonight into Sunday and with it an increase of 850 mb dew pts from -8/-10C at 18z Sat to +8C by 09z Sun. Initial moisture increase looks to be focused into central and eastern ND heading into tonight and Sunday. Then rain chances taper off from the west Sun night into Monday as main moisture shifts east. Overall WPC QPF shows high chances of around 0.75 inch on average. NBM probs indicate 40-60 pct chance of 1 inch or more of rain in the 48 hour period 00z 18Z Sat to 18z Mon. Some thunder possible in SE ND late Sunday. PWATs over 1 inch forecast as well in E ND and western MN, so this would support potential for 1 inch rainfall. For most areas this will be beneficial rains due to the dry fall. Harvest is mostly done as well. ..Beyond Monday... Main moisture moves east and cooler air moves back in with some weak short waves and small chances for light rain showers mainly Wednesday for western and north central ND. Next 500 mb south to southwest flow event sets up late next week and next weekend and timing differences exist between all the global models. Temperatures suggest any precipitation will remain liquid as temps remain above normal. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 649 AM CDT Sat Nov 2 2024 11z-12z obs showing their usual downturn, with many sites IFR east and west of the valley with low ceilings. Clear area Cavalier to Grand Forks airport and this causing some patchy fog. The whole idea of how things transition today sky cover wise is uncertain. Should see improved conditions at least with rising ceilings midday into MVFR range at least. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...TT DISCUSSION...Riddle AVIATION...Riddle