Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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841 FXUS63 KABR 132328 AFDABR Area Forecast Discussion National Weather Service Aberdeen SD 628 PM CDT Thu Jun 13 2024 .KEY MESSAGES... - A more active weather pattern sets up beginning Friday afternoon, and will continue into at the least the first half of next week. This will bring multiple opportunities for showers and thunderstorms to the region (30-60% chance). The greatest chance for severe weather will be on Monday along and east of the James River Valley. && .UPDATE... Issued at 627 PM CDT Thu Jun 13 2024 Few changes will be made to the ongoing forecast, with a clear sky and temperatures falling into the 50s tonight. && .SHORT TERM /THIS EVENING THROUGH FRIDAY NIGHT/... Issued at 312 PM CDT Thu Jun 13 2024 Upper level ridging will build over the region tonight and through the morning hours on Friday. The flow will become more zonal Friday afternoon as a shortwave trough crosses the Rockies. The trough will be strongest south of the region, with just the far southern part of the CWA getting clipped by some energy Friday night. At the surface, high pressure will be the dominant feature over the area tonight and Friday morning, keeping conditions dry. The high will then get pushed to the east, with the region becoming situated between it and low pressure to the west Friday afternoon. Southerly flow will increase across central South Dakota and will bring increased moisture to the area. Precipitation chances will also increase, first across central South Dakota Friday afternoon, then across the entire area Friday night ahead of the low pressure system, which will reach western South Dakota by late Friday night. Severe chances look pretty minimal, but may be a bit more elevated across the southwestern CWA Friday evening closer to the aforementioned shortwave energy, and where 1000-1500 J/kg of MUCAPE and 45 knots of bulk shear look to develop. Low temperatures tonight will be in the lower to mid 50s. High temperatures on Friday will be in the upper 70s to mid 80s. Lows Friday night will be in the lower to mid 60s. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Issued at 312 PM CDT Thu Jun 13 2024 The upper flow pattern will continue to remain active through most of this period with multiple waves or disturbances moving through the region, each giving us a chance for showers and thunderstorms. The first in a series of waves will be upon us at the start of the period on Saturday. Ensemble clusters show an upper level trough will be positioned across the western CONUS and PacNW. With a shortwave ridge shifting east of our region by the start of the weekend, southwesterly flow aloft will become the predominant pattern across the Northern Plains and Upper Midwest. Sfc low pressure and associated frontal boundary is progged to be located off to our west on Saturday, across parts of the western Dakotas and Northern High Plains. Southerly low level flow increases through the day with increasing humidity and temperatures. Instability does increase ahead of the boundary later in the day on Saturday but we also anticipate the potential for capping as warm air floods in at the mid levels. Deep layer shear isn`t all too impressive(20-25kts) ahead of the boundary across our area. Better chances for severe potential will be across parts of western ND and southeastern SD by Saturday night. The focus for strong to severe storms across southeast SD will be the result of a better shortwave lifting northeast out of NE into IA and MN Saturday into Saturday night. Precip chances are higher in our east as a result where there is potential for some heavy rain. Portions of northeast SD(east of the James Valley) into west central MN have a 15-35% chance for seeing a 0.5" of rain in a 24 hr period ending by late Saturday night. The frontal boundary is poised to shift eastward and through the CWA late Saturday into Sunday and then begin to stall out to our east and/or slowly lift back to the north and west early next week. Sunday still looks to be the drier day of the two for the upcoming weekend before the next shot of moisture and potential for strong to severe storms return Monday. Another disturbance in that series is expected to shift through the region on Monday. Sfc low pressure will slide along that aforementioned stalled front across parts of eastern SD/western MN and be the focus for showers and storms. With a southwesterly mid level jet along with a moist and unstable environment in place, ingredients will be in place for convection, perhaps strong to severe. We also me be dealing with some capping issues though too for some areas of the CWA, at least earlier on in the daytime hours. That could change by days end with a better chance for severe convection kicking off Monday night into Tuesday. SPC continues to highlight our eastern forecast area with the Day 5 15% severe risk and that seems to be reasonable at this time. Timing and placement differences among guidance continue to lend to lower confidence in how this severe event will eventually play out. The pattern really remains fairly consistent Tuesday through Thursday next week. An upper trough across the PacNW is progged to shift eastward across the Northern Rockies with continued multiple disturbance riding through the flow across our region. This will give us continued off and on chances for showers and thunderstorms through the end of the period. Overall, temperatures through the period will remain seasonal if not above normal at times with highs generally in the upper 70s and 80s and overnight lows in the mid 50s to mid 60s. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 627 PM CDT Thu Jun 13 2024 Terminals KABR,KATY,KPIR,KMBG VFR conditions will continue through the period. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...KF SHORT TERM...Parkin LONG TERM...Vipond AVIATION...KF