Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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725 FXUS63 KABR 281505 AAB AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1005 AM CDT Fri Jun 28 2024 .KEY MESSAGES... - There is a Marginal Risk (1 out of 5) for severe weather for much of the area later today. A few strong to severe thunderstorms are possible late this afternoon and this evening, but widespread thunderstorm activity is not expected. - Another opportunity for showers and thunderstorms will arrive later Sunday into Monday (30-70% chance of measurable rain). && .UPDATE... Issued at 952 AM CDT Fri Jun 28 2024 No changes planned to the today period forecast. Later this afternoon/evening, there will be a wind-shift/frontal boundary sweeping through central/north central South Dakota. Not much instability (mlCAPE ~250-500J/kg), but the deep layer shear is on the order of 45 to 55 linear hodograph knots (high shear/low CAPE environment). Not suggesting there will be copious amounts of severe thunderstorm activity later, but if a couple of thunderstorms were to develop, they would likely be supercellular and not very tall and probably not look like all that much on radar. Will have to see what type of wind/hail threat there could be. UPDATE Issued at 623 AM CDT Fri Jun 28 2024 See updated aviation discussion below. && .SHORT TERM /TODAY THROUGH SATURDAY AFTERNOON/... Issued at 312 AM CDT Fri Jun 28 2024 The region will be under upper level southwest flow today ahead of an approaching shortwave trough. This trough will track across the CWA tonight, leaving northwest flow it its wake on Saturday. At the surface, an area of rain and thunderstorms is currently tracking across the eastern part of the CWA, and expect this activity to exit to the east by early this morning. Conditions will be fairly quiet during the day, then the region will become situated between low pressure to the east and high pressure to the west tonight. Not much in the way of instability expected later this afternoon and evening, but will see some areas of shear in excess of 60 knots. CAMs are indicating the potential for a few thunderstorms, but do not expect widespread activity. The high to the west will track eastward and settle in over the Northern Plains on Saturday, keeping conditons dry and a bit cooler. High temperatures today will be in the upper 70s to lower 80s. Low temperatures tonight will be in the 50s. Highs on Saturday will be in the mid 60s to lower 70s. && .LONG TERM /SATURDAY EVENING THROUGH THURSDAY/... Issued at 312 AM CDT Fri Jun 28 2024 Saturday night, we start the long term on the downwind side of an approaching ridge. This will remain in place through the day Monday. Monday evening, an upper level trough will make its way across the region bringing a chance for rain and possibly some severe storms. After that, we pretty much stay in a trough pattern aloft. A couple shortwaves move through and Thursday night an upper level low starts to move down out of Canada. This is still 6 days out so there is a lot of variation in tracks. The GFS has the strongest low at the moment but generally keeps it in northern ND and MN. The EC has the weakest low and brings it into northeastern SD. The Canadian is in the middle and brings the low right across SD into northwestern IA. Our first chance for some precipitation will be Monday as that upper level trough moves through the region. This is expected to move northeast through the day bringing the warm front up from the south. Some severe storms could form along this boundary or along the cold front behind it. SPC has already highlighted most of eastern SD in a 15% risk for severe storms. Tuesday and Wednesday will feature slight to chance pops (15 to 25%) as we continue in a trough pattern with some energy moving across. Thursday, ahead of the low, chances increase to 35 to 50% through the day. Storms are possible, however, severe potential is uncertain. Temperatures throughout the period will be in the mid 70s to mid 80s, between 10 degrees below average and right around average. Sunday afternoon could have some gusts of 30+ mph around and west of the Missouri River as a result of a stronger pressure gradient ahead of the incoming low. Gusts around 30 mph are expected to continue through the overnight hours and into Monday moving west to east and diminishing Monday evening. For now, winds look to remain around normal for the rest of the period. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 623 AM CDT Fri Jun 28 2024 Terminals KABR,KATY,KPIR,KMBG There may be a few periods of MVFR cigs across the eastern part of the area early this morning. Otherwise, VFR conditions will prevail across the area today into this evening. A few thunderstorms may develop during the evening hours and may be strong to severe, but widespread thunderstorm coverage is not expected. Therefore, will not mention them in any of the TAFs. MVFR cigs will settle in over the northern and eastern parts of the area late tonight. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Dorn SHORT TERM...Parkin LONG TERM...KK AVIATION...Parkin