


Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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898 FXUS63 KBIS 162025 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 325 PM CDT Wed Jul 16 2025 .KEY MESSAGES... - Light showers will continue across the south central and southeast through the afternoon. - Areas of wildfire smoke may return this afternoon through tonight across the west. - Well below average temperatures through Thursday, with near- record cold highs in the 60s today. - Dry tonight and Thursday, then medium chances for showers and thunderstorms Thursday night through Friday, and again Saturday night through Sunday. && .DISCUSSION... Issued at 325 PM CDT Wed Jul 16 2025 This afternoon, broad surface high pressure was centered across the southern Canadian Prairies and into northwest North Dakota, underneath a shallow trough embedded in longwave troughing extending across much of the CONUS. A few embedded vort maxes have been rotating through the trough base, leading to on and off rain across the southern part of the forecast area. At this point, rain is primarily limited to the far south central and southeast, with no additional development expected for the rest of the afternoon and evening. Clouds are expected to diminish through the evening as the high pressure drifts southeast, with seasonably chilly lows tonight. Current forecast has widespread 40s tonight, but can`t rule out the typical cold spots (Hettinger to Glen Ullin corridor) dropping into the upper 30s, with the latest NBM giving this a roughly 20 percent chance of occurrence. Synoptic flow becomes more zonal on Thursday, with a few CAMs showing some very light morning rain showers in the southwest, although opted to keep forecast dry at this point. Temperatures begin a slow warming trend, with highs in the mid 60s to lower 70s and a bit of a southeast breeze during the day. Another embedded trough is progged to drop south through the area later Thursday night, with long-range CAMs beginning to advertise scattered convection on the nose of a low-level jet. Midday update did add in mention of isolate severe thunderstorms across parts of the west and into the south central, with main hazards of hail up to the size of ping pong balls and wind gusts up to 60 mph. There is quite a lot of bulk shear being advertised, on the order of 60 knots, although instability is marginal at best, generally under 1000 J/kg. HREF does paint some UH tracks starting in the late evening and continuing through part of the overnight hours. That surface trough will get washed out quickly on Friday, as precipitation chances diminish through the afternoon and evening. Friday evening and much of Saturday should be dry in between waves, with highs on Saturday in the mid 70s to lower 80s. A shallow ridge will be building in through the day Saturday, just downstream of a trough and closed low moving over British Columbia and Alberta. As the low approaches, precipitation chances start Saturday night, with machine learning guidance beginning to advertise increasing potential for severe weather across western North Dakota. Things bump up further on Sunday as longer lead deterministic guidance has a swath of sufficient buoyancy and bulk shear to support severe convection, mirrored in higher probabilities in machine learning guidance across much of the state. This trend continues through the start of the work week, as the original trough gets washed out but a secondary one digs over the Pacific Northwest, leading to southwest flow aloft across the Dakotas, a favorable pattern for severe storms across our area. High temperatures during this period are forecast generally in the 80s, with low chances of exceeding 90 degrees across the south Sunday and Monday. By the time we get to the middle of next week, cluster analysis reveals some modest differences in the placement of the ridge axis, which will influence the flow pattern over the Dakotas. Extended severe weather probabilities still keep some modest chances across the state through the end of next week, with NBM temperature percentiles advertising a bit of a cooldown late week before warming up next weekend. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1240 PM CDT Wed Jul 16 2025 Overall VFR conditions expected through the TAF period. A few areas of rain are ongoing across the south, potentially impacting KBIS and KJMS through the afternoon hours, which could lead to reduced visibilities. Northeast winds will become light and variable overnight before shifting to southeasterly on Wednesday morning. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Jones AVIATION...Jones