Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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032 FXUS63 KBIS 160016 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 716 PM CDT Wed May 15 2024 .KEY MESSAGES... - Daily chances for precipitation continue through the week into early next week. - A low potential for a strong or severe storm Friday afternoon/evening. - Warming trend through Friday, then a modest cooldown for Saturday. && .UPDATE... Issued at 715 PM CDT Wed May 15 2024 Scattered showers are being maintained over the James River Valley early this evening by an inverted surface trough underlying the base of a mid level trough. This activity should diminish closer to sunset. Extensive cloud cover wrapping around the surface low over far west central Minnesota continues to slowly erode from west to east over central North Dakota this evening. Due to the clearing skies with light winds and residual boundary layer moisture, we anticipate some patchy fog developing later tonight into Thursday morning, mainly across areas including Linton, Bismarck, Steele, Harvey, Rugby, and Rolla. Isolated to scattered showers preceding a shortwave ejecting off the Canadian Rockies are ongoing across northeast Montana. At 7 PM CDT, a couple of isolated showers were approaching the state border, while a more persistent line of showers with occasional lightning was tracking east through Glasgow. The PoP forecast has been updated to account for observed trends. && .DISCUSSION... Issued at 134 PM CDT Wed May 15 2024 Current surface analysis places low/trough over the eastern Dakotas, with frontal boundary dropping southward through the plains. Upper level analysis places trough stretching from the Northern Plains south/southwestward towards the central/southern Rockies. Over our area, some light rain showers continue to gradually dissipate over the James River Valley, while lingering low cloud cover over much of the area has started to diminish in earnest over western areas. For the rest of this afternoon into tonight, clouds will continue to gradually diminish from west to east, with showers ending as the aforementioned upper trough over the area pushes east. West-northwest flow sets up over our area but a modest short wave will make its way through the flow and start its approach late tonight, bringing low rain chances (~20 percent) to northwest parts of the area. The wave will continue its way across northern parts of the area Thursday morning, with continued modest chances. As we go through late Thursday into Thursday night, a trough drops into the Pacific Northwest with flow shifting southwesterly over our area and becoming active. This will bring the start of an extended period of shower/thunderstorm chances. At this time Friday looks to bring the greatest chances, especially overnight over central and southwest North Dakota (60-80 percent). There is a hint at some strong to severe thunderstorm potential as models are hinting at elevated instability (possibly 500-1000 J/kg) with ample deep layer shear for rotating updrafts. The fly in the ointment may be the timing of the forcing, as that seems to be overall lagging a bit as of this moment. With that said, the potential for the timing to eventually overlap a bit is there, and is being picked up by the CSU machine learning severe guidance which is showing a potential over central and parts of southwest North Dakota, so will continue to monitor. Friday also looks to be the warmest day, with highs pushing into the mid 70s to mid 80s. Cooler air moves in for Saturday, with a modest rebound for the upcoming week. Pattern remains active, with daily chances (20-40 percent) for precipitation. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 715 PM CDT Wed May 15 2024 Scattered showers will reduce visibility to MVFR/IFR levels at KJMS this evening. Ceilings will continue to improve to VFR levels from west to east across central and eastern North Dakota through the evening. A separate area of scattered showers over northeast Montana this evening could slowly move across western and central North Dakota overnight into Thursday morning. The highest chances for a shower are at KXWA. Additional shower and thunderstorm development will be possible Thursday afternoon. Light winds are expected through tonight, becoming westerly around 10 kts on Thursday. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Hollan DISCUSSION...JJS AVIATION...Hollan