Andes Tower Hills Snow Report

403 FXUS63 KFGF 290453 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1153 PM CDT Mon Sep 28 2026 .KEY MESSAGES... - Widespread soaking rainfall with embedded thunderstorms will continue this afternoon through tonight. Localized flooding impacts may occur in portions of southeast North Dakota into central and southern Red River Valley from rainfall amounts 3 to 6 inches. && .DISCUSSION... Issued at 301 PM CDT Mon Sep 28 2026 ...Synopsis... Broad southwest flow aloft currently resides over the Northern Plains and Upper Midwest as a result of longwave upper troughing in the West. This is helping draw northward increasing moisture content, while also allowing several shortwave troughs embedded within the flow aloft to provide forcing for ascent to drive widespread rainfall into the eastern Dakotas and northern Minnesota this afternoon through tonight. Weak but sufficient instability accompanying the surge in moisture will also allow embedded thunderstorms to be present, especially tonight. Two or more "waves" of rainfall with embedded thunderstorms will drive potential for training higher rain rates - bringing potential for localized flooding impacts. More details on this potential found below. Tuesday morning, rainfall should end west to east, with most/all of the area becoming dry by the afternoon. This will usher in a relatively dry period through the remainder of the week, with the exception of some transient showers potentially late week/weekend, but ultimately resulting in little rainfall amounts, if any. This is a result of generally zonal to northwest flow aloft amid upper ridging building over the High Plains/Intermountain West. Near to above average temperatures are forecast through Wednesday, turning average to below average temperatures late this week. ...Potential flooding impacts this afternoon & tonight... There remains potential for an additional 3 to 6 inches of rainfall this afternoon through tonight in portions of southeast ND, central/southern Red River Valley, into northwest MN. The majority of CAMs continue to paint this scenario somewhere within the aforementioned areas, but each with their own variety of exactly where this will occur. Locations that experience these amounts are liable to see flooding impacts. Confidence is relatively high in this output based on the presence of a stationary boundary extending southwest to northeast generally from the southern James River Valley in southeast ND into the central Red River Valley into northwest MN. This sets the stage for additional upper forcing to act upon, which is well advertised to resurge tonight in the form of a shortwave trough propagating out of the High Plains of WY/SD, through the Dakotas, and into northwestern ON by Tuesday morning. This will help reinvigorate the low level jet within the "warm sector" of the aforementioned stationary front - suggested to generally remain in this orientation/position through the event, with some eventual movement eastward Tuesday morning. Abnormally high moisture content (~1.5 inches of PWATs) coupled with weak but sufficient instability (MUCAPE ~800 J/kg), and storm motion generally parallel to frontal orientation will drive high rain rates. Rain rates like 0.5-1" per hour and/or 2-4" per 6 hours will result in areas that see repeated thunderstorms move over any particular location for at least 2 hours. Pre-conditioned areas that have recently experienced soaking rainfall is also important to consider when identifying potential areas for subsequent flooding impacts. While these advertised highest rain rates may occur in northwest MN, higher rain amounts from this morning have generally missed this area. Conversely within southeast ND, rainfall from this morning in the 1-2 inch range have already occurred, with continued convective rates from thunderstorms still ongoing in southeast ND at the time of this Forecast Discussion issuance. Despite this area in drought, higher rain rates coupled with previously/currently received rainfall still allow for excessive runoff. Of course, urban areas are relatively more susceptible to these higher rain rates; this includes cities like Fargo-Moorhead and/or Valley City. While the overall area of concern holds generally medium to high confidence, more precise location of highest rainfall amounts remain in question. Because of this, have opted to not issue a Flood Watch; however, a Flood Watch may be issued should confidence increase in more precise location of potential area of concern later this afternoon/early evening. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 1153 PM CDT Mon Sep 28 2026 Highly variable flight conditions as a frontal zone lingers over the region and clusters of showers and embedded thunderstorms track southwest to northeast. Many locations are reporting MVFR and IFR conditions. Stratus should fill in through the overnight hours and IFR ceilings will become predominant with the potential for LIFR (mainly KDVL). Fog may also develop in areas outside of showers tonight/Tuesday morning. Drier air does eventually arrives Tuesday and VFR should return to ND by early afternoon, with a slower west to east period of improvement in the afternoon/evening across northwest MN. MVFR ceilings may linger over north central MN including KBJI through Tuesday evening. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Flood Watch until 5 AM CDT Tuesday for NDZ038-039-049. MN...Flood Watch until 5 AM CDT Tuesday for MNZ003. && $$ DISCUSSION...CJ AVIATION...DJR