


Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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940 FXUS63 KFGF 041228 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 728 AM CDT Fri Jul 4 2025 .KEY MESSAGES... - There is a level 2 out of 5 risk for severe storms in the afternoon and evening today. Main hazards will be flash flooding, wind gusts to 60 mph, and hail to the size of quarters, along with frequent lightning. - Heat related impacts today due to high temperatures and high dew points. && .UPDATE... Issued at 724 AM CDT Fri Jul 4 2025 The last of the showers and t-storms with the t-storm complex is exiting Lake of the Woods while a small area of showers are moving northeast to the north of Devils Lake. I would suspect by 14z or so no precipitation will be in the fcst area. Enough sun as the clouds clear out to warm everyone up as forecast. 06z NAM and latest HRRR indicate conitnued good agreement in having a boundary and t-storm development around 21z Warroad to Grand Forks to Cooperstown. && .DISCUSSION... Issued at 308 AM CDT Fri Jul 4 2025 ...Synopsis... Outflow boundary with north-northeast winds has been dropping south and and passed Devils Lake and will likely go through Grand Forks, Thief River Falls with main rainfall activity and t-storms holding farther north closer to the border. This wind shift should wash out this early morning with winds at 12z likely turning back southeast or be light/variable in northeast ND and far NW MN, with a south wind 10-25 kts in SE ND and WC MN. Frontal boundary at 12z likely will still be well northwest of the area from near Estevan into northeast Montana. This frontal boundary moves east. It seems that short term models want to develop t-storms early to mid aftn in the zone of more variable wind right ahead of the front where it bumps up with a steadier south wind. That boundary looks to be from about Roseau to Grand Forks to Cooperstown at 00z. Cooler and less humid airmass follows for the weekend. ...Severe risk and heavy rain potential for this afternoon and tonight... Models in general agreement in developing an axis of thundertorms by 21z along a boundary from near Roseau/Warroad to Grand Forks to Cooperstown to Jamestown/Bismarck. Sfc CAPE from NBM 3km shows over 4000 j/kg just ahead of boundary at 21z where temps likely in the mid 90s Bemidji to Fargo. Sfc CIN values at that time becomes negligble, or foreast to be. Thus a rapid increase in storms anticipated around 21z along the boundary and the area of storms will grow and slide gradually east/southeast in time thru the evening. PWATs around 2.3 inches would certainly favor heavy rainfall potential with high rainfall rates leading to potential for urban flooding. Most of the area in June saw rainfall deficits of 1.50 to 3 inches in the area where storms will form and where highest rainfall amounts are forecast. Thus feel outside of rapid rainfall rate flooding in areas of poor drainage, streets, the ground will be able to absorb most of it where it falls on grassy surfaces, fields. No flood watch issued at this time due to this and usual uncertainity in exactly where heaviest rainfall will be. Severe weather is more uncertain. Early on in the development of the line, large hail and wind gusts 60 mph or higher is possible before it turns into more of a heavy rain threat. SPC has area in 2 pct tornado threat and think that would be short lived and in the early stages of development. Shower and t-storm chances linger in SE ND into MN into much of Sunday before pushing east. ...Heat today... Heat indices will reach the upper 90s to low 100s in most areas, except DVL basin. So will maintain the heat advisory. Wet bulb globe temp is in the high and extreme values (mid 80s). && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 724 AM CDT Fri Jul 4 2025 High level clouds this morning, thicker in the north with some mid clouds mixed in. South wind 10 to 15 kts SE ND into MN and a variable wind 5 to 10 kts in northeast ND and far NW MN. Focus for today will be development and timing of the t-storms and how long they persist at any one spot. Also vsby and ceilings. DVL has the lesser chance but high chances at the other TAF sites mid aftn or evening. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Heat Advisory from 11 AM this morning to 7 PM CDT this evening for NDZ027-029-030-038-039-049-052-053. MN...Heat Advisory from 11 AM this morning to 7 PM CDT this evening for MNZ001>003-005>009-013>017-022>024-027>032-040. && $$ UPDATE...Riddle DISCUSSION...Riddle AVIATION...Riddle