Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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796 FXUS63 KBIS 181143 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 643 AM CDT Sat May 18 2024 .KEY MESSAGES... - Windy and cooler today with highs mostly in the 60s. A Wind Advisory is in effect from mid morning through this afternoon for northern and central North Dakota. - A chance of afternoon and evening thunderstorms Sunday far southwest and south central, some possibly strong to severe. - Seasonable temperatures through the work week with morning lows in the upper 30s to mid 40s and daytime highs mainly in the 60s. Periodic chances for showers and thunderstorms continue through the work week. && .UPDATE... Issued at 631 AM CDT Sat May 18 2024 Shortwave pushing through central ND is producing a narrow band of shower activity along the Highway 83 corridor. This shower activity will continue to track east, exiting the forecast area later this morning. Otherwise windy conditions are expected across the area today with advisory criteria winds mainly over northern and central ND. Updated PoPs and sky cover based on latest radar and satellite imagery. Updated text products will be transmitted shortly. && .DISCUSSION... Issued at 221 AM CDT Sat May 18 2024 Currently, thunderstorms are exiting the southern James River Valley. An area of rain showers continues to push from western and into central ND ahead of a shortwave lobe pushing into western ND. Surface low pressure is exiting eastern ND as high pressure is pushing into the western Dakotas from the Northern Rockies. This is producing a strong pressure gradient currently over western ND. Winds are gusting into the 40 to 50 mph range over southwest ND. The shower activity is likely adding to the gusts and this brief bump in winds can be traced west to east across southern ND this morning from the bufkit soundings. This brief bump in winds is not expected to last long as it propagates east through mid morning. Later this morning and this afternoon, strong gradient winds will remain across northern and central ND between the low that lifts northeast into Canada and the surface high that slides southeast into South Dakota. We have issued a wind advisory (in effect from mid morning, through the afternoon) for northern and central ND, along and north of the I-94 corridor. The gradient isn`t all that strong but steep lapse rates and good afternoon mixing should result in low end criteria wind advisory winds over a good portion of the forecast area. Although the aforementioned brief bump in winds tracks across the far south early, daytime wind potential will be lowest across the far southern tier counties. Winds diminish quickly tonight and we see low drop into the 40s, with some upper 30s possible in the north and west as surface high pressure propagates across the forecast area. another shortwave rotating around the mean upper low situated over southern Canada tracks across the Northern Rockies on Sunday. Surface low pressure will develop in the lee of the Northern and Central Rockies and exit into the plains during the day. By Sunday afternoon, deterministic guidance is depicting surface low pressure over South Dakota with a southwest upper flow from the Central Rockies into the Northern Plains. This will set the stage for a possible round of thunderstorms Sunday afternoon and evening tracking through the Dakotas. Based on the deterministic and ensemble location of the surface low, there would be a risk of strong to severe storms over south central into southeast North Dakota Sunday afternoon/evening. SPC has placed portions of south central ND (Sioux/Emmons east through Lamoure/Dickey counties) in a marginal risk for severe storms, with a general risk of thunderstorms over the far southwest and the remainder of south central ND. Based on the location of the surface low, all threats would be in play, including tornados. CSU_MLP has the low tornado probs up to the SD/ND border in south central ND. Bufkit sounding from Ashley shows a very warm, moist and highly sheared environment, but potentially capped. With a decent shortwave moving into the area, the potential will be there for enough forcing to initiate convection. Will certainly continue to monitor the south central for severe potential tomorrow afternoon/evening. Once this wave moves through Sunday/Sunday night, it looks like we may have at least a brief break in the convection early next week. The aforementioned upper low will linger over southern Canada pretty much through the work week. The next wave coming off the Pacific may take more of a southern track into the Central Rockies before lifting back north and east as it tracks through the central portion of the U.S. There is quite a bit of uncertainty in whether this wave misses us, or clips southern and eastern portions of the forecast area on Tuesday. Beyond this, the barrage of upper lows lifting into the Northern Plains continues through remainder of the forecast period. Temperatures remain seasonable next week with morning low in the upper 30s and 40s and daytime highs mostly in the 60s. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 631 AM CDT Sat May 18 2024 MVFR ceilings possible this morning at KXWA, KDIK and KMOT. Added a TEMPO for MVFR ceilings at these sites through around 14-16 UTC. Otherwise VFR conditions are expected through the TAF period at all sites. West winds across the area late this morning and this afternoon 25-30 mph with gusts to around 45 mph through 00 UTC. && .BIS WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 10 AM CDT /9 AM MDT/ this morning to 7 PM CDT /6 PM MDT/ this evening for NDZ001>005-009>013-017>023-025- 031>037. && $$ UPDATE...TWH DISCUSSION...TWH AVIATION...TWH