Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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935 FXUS63 KBIS 262312 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 612 PM CDT Sun May 26 2024 .KEY MESSAGES... - Showers and thunderstorms likely through the evening, becoming more isolated tonight. An isolated strong storm is possible with small hail and gusty winds. - Isolated to scattered showers and thunderstorms return on Memorial Day. High temperatures will generally be in the 60s. Some breezy northwest winds may be found across the south. - Generally dry conditions and warming temperatures to be found Tuesday into Wednesday. - Later Wednesday through the end of the work week, precipitation chances return while temperatures remain near to slightly above normal. && .UPDATE... Issued at 548 PM CDT Sun May 26 2024 Scattered to numerous showers and isolated thunderstorms continue to track eastward across western and central North Dakota early this evening. We`ve had a report or two of some pea sized hail and have seen gusts to around 35 mph with a few of the stronger thunderstorms. Most of the activity has produced brief heavy rainfall. If you do have outdoor plans this evening, remain alert to the potential for thunderstorms amongst the general shower activity and move indoors if you hear thunder. We made some small adjustments to pops and sky cover based on the latest radar and satellite imagery. Otherwise no changes to the going forecast. && .DISCUSSION... Issued at 340 PM CDT Sun May 26 2024 Shortwave trough wrapping around a stalled upper low in Canada will bring widespread showers and thunderstorms through this evening. A few of these storms could be strong as MUCAPE of near 1000 J/KG will be found. The skinny cape profile though should make large hail tough, as well as the overall lack of shear. Expect more pulse like thunderstorms that may be strong briefly then diminish, and could produce hail of a half inch to an inch. Inverted V soundings and small amounts of DCAPE could also promote some gusty winds of 50 to perhaps 60 MPH in the strongest storms. Once the wave moves more eastward later this evening through tonight showers and thunderstorms should become more isolated tonight. Lingering cloud cover should keep overnight lows in the 40s, limiting the frost potential. There could be some lower clouds or perhaps patchy fog tonight. Fog is not in the forecast at this time, although northern and eastern areas do have some potential for this to occur. The main upper low in Canada looks to move southward on Memorial Day extending a trough into North Dakota. This could bring some isolated to scattered showers and thunderstorms. Instability looks even less for Monday, with shear also remaining low. Thus severe thunderstorms are not expected at this time. THe increased gradient could bring some breezy northwest winds on Memorial Day, mainly south and east. Look for temperatures to be slightly below normal and in the 60s. Skies go on a clearing trend Monday night, with wind also going light. This could bring some cool temperatures and perhaps some patchy fog. Lows in the upper 30s to upper 40s are forecast. Perhaps some patchy frost could return to the north central if overnight lows dip further, which will have to monitored. Tuesday, a building ridge will bring mainly clear skies and dry conditions. Areas closer to the ridge in the west will see warming temperatures, while eastern areas remain in the northwest flow pattern and see cooler temperatures in the 60s. Ridge starts out overhead on Wednesday, with a transition to southwest flow aloft throughout the day. A developing low lee of the northern Rockies could bring tight pressure gradient. This could bring a warm yet breezy to windy southerly flow. This unsettled setup could also return showers and thunderstorms to the west Wednesday afternoon and evening. Instability and shear go on the increase during this time period, perhaps bringing some strong to severe thunderstorms as also indicated by the CSU-MLP. A front and the upper wave then looks to move through on Thursday. CSU-MLP also showing the possibility of severe weather when this does so, which will also have to be monitored. A breezy southerly wind could become a breezy westerly wind depending on the timing of this wave. Warm temperatures on Wednesday may also linger into Thursday, also depending on timing. An upper low may then linger across southern Canada through much of the upcoming weekend. The resultant westerly flow could continue to bring near to slightly above normal temperatures. This unsettled pattern could also bring some showers and thunderstorms, although predictability at this point is low and the NBM generally maintains slight pops at times through this time period. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 548 PM CDT Sun May 26 2024 Scattered to numerous showers and isolated thunderstorms continue to move east across central and western ND. Thunderstorms activity around KMOT and KBIS at this time and may need to include Thunder to begin the TAF. Will include VCTS elsewhere to begin the TAF period, except KDIK which activity has moved out of the southwest. Shower activity will diminish later this evening. Late tonight into Monday morning a band of MVFR clouds is expected to drop south from Canada and clip KMOT, KBIS and KJMS with a period of MVFR cigs mid morning to early afternoon. KDIK and KXWA currently expected to remain VFR. Isolated to scattered shower activity is expected again Monday afternoon with best chances north and east. Too far out at this time to include in any TAF. Light surface flow central ND and westerly flow in the west becomes west to northwest this evening then northwest to north Monday generally 10 to 20 knots. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...TWH DISCUSSION...TWH AVIATION...TWH