Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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367 FXUS63 KBIS 062048 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 348 PM CDT Thu Jun 6 2024 .KEY MESSAGES... - Windy conditions will continue through the day, with sustained northwest winds up to 35 mph and gusts up to 50 mph. - A weak wave will bring chances (20 to 40%) for showers to the central and James River Valley areas on Friday. An isolated thunderstorm is possible in the south central and southern James River Valley in the afternoon and evening. - After a drier weekend, chances (20 to 40%) for showers and thunderstorms return to western and central North Dakota on Monday and Tuesday. - A warming trend is then expected to begin through the rest of next week. && .DISCUSSION... Issued at 348 PM CDT Thu Jun 6 2024 At the moment, North Dakota sits under northwesterly upper level flow, with a large trough digging across the Great Lakes to the east, and a very broad ridge positioned across the western CONUS. With lower surface pressure to the east, and higher pressure to the west, a somewhat strong pressure gradient oriented northwest to southeast also sits across the entire state, helping bring about some rather strong northwesterly winds to much of western and central North Dakota. Earlier model soundings suggested the potential for 40 to 50 kt winds atop the mixed layer paired with inverted-V profiles, which seems to have nearly entirely transitioned these winds to the ground at this point. Many reports of sustained northwesterly wind speeds in the mid to upper 30 mph range have been reported today, with some gusts approaching 50 mph, exceeding 50 mph in isolated instances. As such, we`ve continued our Wind Advisory, which goes until 7 PM CDT tonight, when winds are expected to decrease around sunset. There have also been some reports of these winds kicking up dust, most notably across the southern James River Valley, which could potentially reduce visibilities to a half mile at times. We`ve added in some patchy blowing dust to the forecast in this area as well, until the Wind Advisory ends. While wind speeds are approaching warning criteria, they`ve largely remained below, so we will continue with a Wind Advisory at this time. Otherwise, generally clear skies are expected, with some fair weather cumulus across the central and James River Valley areas through the daytime hours. Highs today are largely in the 70s, with overnight lows tonight in the 40s. Heading into Friday, the aforementioned ridge is expected to flatten out somewhat, as a quick moving shortwave trough drops southeast through the area. Due to the transient nature of this wave, chances for precipitation (mostly 20 to 40%) moves through the area from the northwest corner to the southern James River Valley essentially through the daytime hours. A small corridor of modest instability and buoyancy across the south central may bring about some thunderstorms for a few hours in the evening, though the chance for these becoming severe is near 0. Otherwise, highs on Friday are expected to range from the mid 60s in the north to the upper 70s in the south. Some areas in the far south may see temperatures climb into the 80s. Overnight lows are expected to remain largely in the 40s. Through the weekend, the upper level pattern does not change very much, and as such, the conditions across our area will be rather similar Saturday through Monday morning. With a trough positioned to our north, slowly descending south through Saskatchewan and Manitoba, we remain under northwesterly upper level flow. Northern portions of our area may see occasional sprinkles or showers, but for the most part, we are expecting drier conditions, with highs consistently in the upper 60s to mid 70s during this time. A relaxed surface pressure gradient will help keep winds reduced as well. All in all, it seems like it will be a rather quiet period of weather through Monday morning. Our next decent chances for precipitation arrives Monday through Tuesday, as the aforementioned upper level low descends south into the northern Great Plains. With ample forcing associated with this wave, we may see a large swath of 20 to 40% chances for showers and thunderstorms sweep across the state from west to east during this time. Tentatively, long range guidance suggests the potential for some strong storms associated with this wave, however confidence remains rather low. The confidence in this upper level setup in general is somewhat low as well, as the spread in NBM high temperatures also increases during this time. Following this precipitation, long range guidance suggests broad ridging across the western CONUS, building into the Plains and sitting there through the remainder of the week. As such, a warming trend is currently forecast, with highs ranging from the mid 70s to mid 80s by Tuesday and Wednesday. As mentioned before, the NBM spreads in high temperatures are somewhat large, so the confidence in the pattern progressing like this is still not set in stone, but in general, we can anticipate warmer temperatures and drier conditions through the second half of next week. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1230 PM CDT Thu Jun 6 2024 VFR conditions are present across all terminals, with these conditions expected to prevail through the TAF period. Northwesterly winds ranging from 20 to 30 kts are present across much of western and central North Dakota, with gusts up to 40 kts possible through the next few hours. Some fair weather cumulus are also present across the central portions of the state, mainly across KMOT and near KJMS. As we approach sunset, these winds are expected to decrease, becoming more westerly overnight around 5 to 10 kts. Near the end of the TAF period, a quick moving wave will pass through the area, bringing about some mid level clouds and potentially some showers. However, confidence is too low to include this in the last few hours of the TAFs at this time. && .BIS WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 7 PM CDT /6 PM MDT/ this evening for NDZ001>005-009>013-019>023-025-034>037-042-045>048-050-051. && $$ DISCUSSION...Besson AVIATION...Besson