Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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500 FXUS63 KFGF 311506 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1006 AM CDT Fri May 31 2024 .KEY MESSAGES... - Isolated to scattered severe thunderstorms Sunday into Sunday evening. - Another good chance for showers and thunderstorms on Tuesday into Tuesday night. && .UPDATE... Issued at 1006 AM CDT Fri May 31 2024 Patchy fog has cleared across the area, with cloud cover increasing across the southern Red River Valley and west central Minnesota. Temperatures across the area are slowly climbing out of the 50s. Made slight changes to winds to better reflect current conditions, otherwise, the forecast remains on track. UPDATE Issued at 624 AM CDT Fri May 31 2024 Patchy fog has redeveloped this morning near Park Rapids and across Wadena county. A special weather statement was issued in case fog was likely to spread further south. Light showers are still expected near the Canadian Border and portions of the southern Red river valley. Total accumulations of less than a tenth are expected. && .DISCUSSION... Issued at 323 AM CDT Fri May 31 2024 ...Synopsis... Our first departing short wave early this morning has carried the precipitation east of the FA now. The edge of the thicker clouds is staying progressive, and should move east of the FA shortly. There has been some fog along and west of these clouds, which had appeared like it may linger through the rest of the night. Now it appears like it may thin out again or shift to the east, so will monitor and adjust the forecast as needed. There is another weak shortwave setting up along the Canadian border today into tonight. Along with some upper jet forcing, this produces isolated showers and thunderstorms more so this afternoon into tonight. Isolated showers are also possible across west central Minnesota. The parade of waves (and precipitation chances) continues thereafter, with another one Sunday into Sunday evening and Tuesday into Tuesday night. Beyond Tuesday night, model spread really increases, so confidence in the forecast really drops off. ...Sunday into Sunday evening... Should be able to get decent warming on Sunday, with highs expected to be in the 70s to around 80. Plenty of moisture around, with precipitable water values approaching 1.5 inches. 0-6km effective shear values look to be about 30-35 knots. Models are showing a north/south frontal boundary somewhere along a Bismarck to Minot line by 18-21z Sunday, shifting into eastern North Dakota by 00z Monday. So expect thunderstorm development to break out to the west of the FA initially, with some sort of linear complex pushing eastward during the late afternoon and evening. It does look like the low level jet will kick in Sunday night, helping to keep the line going as it moves to the east. SPC has placed most of the FA in a slight risk for severe weather during this period. As far as rainfall amounts, the NBM is showing about a 70 percent chance for amounts greater than 0.25 inches along the South Dakota border, to about a 50 percent chance along the Canadian border. Probabilities for amounts greater than 1 inch drop significantly, about a 5 percent chance along the Canadian border to 20 percent along the South Dakota border. ...Tuesday into Tuesday night... This period also features a pretty good chance for showers and thunderstorms, as the next strong shortwave pushes east along the northern tier states. Being further out, there is still a fair amount of uncertainty in how this event may unfold. However, ensembles are again showing good moisture, with precipitable water values up around 1.25 to 1.5 inches. There are questions on cloud cover and potential heating, with the NBM showing a bit more cloud cover across the northern half of the FA. This could be why the ensembles are showing more CAPE/slightly warmer highs across the southern FA. The NBM shows about a 65 percent probability for rainfall amounts greater than 0.25 inches, dropping to about a 20 percent probability for amounts greater than 1 inch. So these 2 events look similar in that regard. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 624 AM CDT Fri May 31 2024 VFR conditions are expected throughout the day. A cloud deck looks to move over the northern counties. KDVL, KTVF, and KGFK could possible see the layer move in from the north but these clouds look to remain above 10,000ft. Winds will shift from a westerly direction to a southerly direction around 23Z. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...Lynch DISCUSSION...Godon AVIATION...MM