Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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142 FXUS63 KFGF 240429 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1129 PM CDT Thu May 23 2024 .KEY MESSAGES... - Heavy rain tonight into Friday over portions of the Red River basin may bring additional rises on area rivers. - Patchy frost could form Saturday early morning in the Devils Lake basin, although will depend on cloud cover and wind. && UPDATE Issued at 1005 PM CDT Thu May 23 2024 Showers continue to move across the region this evening. A few embedded thunderstorms remain possible, as well as locally heavy rain. Minimal adjustments needed this update, but will be monitoring for localized ponding and overland flood potential associated with the heavier showers. UPDATE Issued at 832 PM CDT Thu May 23 2024 Severe threat has diminished across much of the area this evening. Widespread showers and embedded thunderstorms will continue to move northward through the overnight period, with moderate to heavy rain possible at times. && .DISCUSSION... Issued at 337 PM CDT Thu May 23 2024 Main upper low is still coming out from the northern Rockies into the western Dakotas. Some convection firing in northeastern SD on the leading edge of the 850mb jet and in uncapped 2000 J/kg SB CAPE has mostly been unorganized and not severe. However, the CAMs still break out some more impressive convective cells later on this afternoon and evening. While the main wind shift with the warm front is still mostly down in SD, there is some 55 dew points pooling further north near the I-94 corridor where winds are from the east. That could make some cells moving in that area interesting and could bring some rotation in addition to the main hazards of hail up to two inches and winds to 70 mph. Will continue to monitor how the mesoscale features develop in the next few hours, but it still seems that we will see some good chances for isolated to scattered severe storms during the 21 to 03Z time frame. As the instability decreases tonight, the main upper low will still be coming out into the Northern Plains and the surface low lifting into the Red River Valley. This time the main deformation band sets up more over our northern counties, with the Devils Lake Basin and northern Red River Valley seeing the best probabilities of over an inch of rain. There is even some 50 to 60 percent probability of over 2 inches of rain by Friday evening. The precipitation will continue to wrap around the low pressure system as it lifts off into Canada Friday night. Some colder temperatures start to come down the backside of the system, with some of the models showing a few flakes mixing in the far northwestern counties as early as Friday morning. No accumulations or impacts expected. More cold air coming down as the system pulls east Friday night, although there is some signs of a reinforcing shortwave bringing some clouds that could prevent frost formation. The active pattern continues into the holiday weekend as flow becomes southwesterly, although the bulk of the energy on Sunday seems like it will be to our south. Northern branch shortwave coming through Monday will dig into the Great Lakes Tuesday, allowing ridging to build in and a warming trend for Wednesday/Thursday. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1130 PM CDT Thu May 23 2024 VFR to MVFR conditions prevail outside of showers and thunderstorms tonight, with IFR CIGs expected during showers and embedded storms. Ceilings will slowly fall during the remainder of the overnight period as an upper low traverses the region. Some guidance brings ceilings as low as 600 feet heading into Friday morning before a slow improvement takes shape during the day. Winds are expected to be gusty along a strong pressure gradient associated with the upper low, with sustained winds of 20 knots and gusts to near 30 knots at times. Shower activity will remain in the forecast through at least midday Saturday before slowly moving off to the north and east during the afternoon and evening. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...Lynch DISCUSSION...JR AVIATION...Lynch