Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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126 FXUS63 KBIS 181738 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 1238 PM 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 1228 PM CDT Sat May 18 2024 Winds are increasing as expected with widespread observations of gusts in the 40 to 50 mph range across portions of the west and central. Thus, the Wind Advisory looks to be in good shape. It will remain windy through the afternoon with plenty of fair weather cumulus. A few showers will remain possible through the early afternoon across Bottineau, Rolette, and northern Pierce counties but amounts should be rather light. No major changes were needed for this update. Just blended in the latest observations to the going forecast. UPDATE Issued at 850 AM CDT Sat May 18 2024 No major changes were needed for this update. A few showers continue to linger across the north as an upper low spins to the north of the International Border. 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 /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1228 PM CDT Sat May 18 2024 We will see widespread fair weather cumulus this afternoon but should remain in VFR categories through the period. Some isolated to scattered showers will develop across the south central and James River Valley early Sunday morning before lifting north. Due to the isolated to scattered nature and exact location uncertainty, have not included mention in any site specific forecast at this time. It will remain windy through this afternoon with winds mainly out of the west northwest. Sustained values may reach 30 mph with gusts to 45 mph. && .BIS WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 7 PM CDT /6 PM MDT/ this evening for NDZ001>005-009>013-017>023-025-031>037. && $$ UPDATE...ZH DISCUSSION...TWH AVIATION...ZH