Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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059 FXUS63 KABR 060524 AFDABR Area Forecast Discussion National Weather Service Aberdeen SD 1224 AM CDT Sat Jul 6 2024 .KEY MESSAGES... - Scattered showers and thunderstorms are expected to track from west to east across the region from Saturday morning to Saturday evening. The severe threat is generally low, although a stronger storm or two is possible along and south of US Highway 14. - Isolated shower and thunderstorm chances remain in the forecast on both Sunday and Monday. However, a pattern change seems likely thereafter. Expect a gradual warming trend through the work week. By the end of the week we should be seeing temperatures 5 to 10 degrees above average (highs in the upper 80s-90s). && .UPDATE... Issued at 907 PM CDT Fri Jul 5 2024 Still just a few showers and weak thunderstorms around this evening, mainly across parts of central South Dakota. These will likely dissipate before 10pm with the loss of daytime heating. The next area of precipitation that is expected to affect the CWA overnight is now over western North Dakota and far northwestern South Dakota. No changes made to winds or temperatures at this time. && .SHORT TERM /THIS EVENING THROUGH SATURDAY NIGHT/... Issued at 207 PM CDT Fri Jul 5 2024 Plenty of sunshine, instability (1000-2000 J/KG CAPE) and steep low level lapse rates have resulted in isolated showers and thunderstorms across the region. These should be short lived and will diminish along with the setting sun. The rest of the evening should be dry with lows dropping into the mid 50s/low 60s. Another shortwave will work across the region Saturday. While decent upper level forcing, the low level pressure pattern remains weak. Instability will be limited. Bulk shear does increase across southern South Dakota, with progs around 30kts for areas along and south of Highway 14. This may be enough for a stronger storm or two and the region is in a marginal (1 of 5) risk for severe weather. Showers and thunderstorms may linger into the evening and overnight hours. High confidence in the temperatures forecast. Ensemble Max/Min T spread is generally 5 degrees or less. Expect temperatures to continue to be near or slightly below normal through the weekend. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 207 PM CDT Fri Jul 5 2024 Not too much of a change for the long term as Clusters continue to indicate a highly amplified ridge over the western Conus/Pacific and a trough over the Southern Plains through the Upper Midwest Sunday into Monday. This pattern continues to bring in several embedded shortwaves over the Northern Plains. We finally start to see a shift eastward in the trough and ridge Tuesday. By Wednesday, Clusters "overall agree" on the axis of the ridge over central Canada through the intermountain West (and western Conus). However, Clusters 1 and 3 (made up of mostly EC) keeps the axis slightly further westward than the other ensembles. By the end of the week, the ridge becomes more broad with much of the Conus underneath it into next weekend. There is slight timing and intensity differences of the ridge this far out between the ensembles. At the surface a low is forecasted to be centered over ND/SD/MN border early Sunday morning, along the 850mb trough. Most of the CWA will be post frontal at this point besides eastern SD into west central MN. Through the day this low and front will continue east/northeastward as a high pressure system will move in behind it. Chance of light precip is possible Sunday morning-midday (15-30%) before chances increase with diurnal heating to 30-45% across the CWA with this system. Just enough afternoon instability (up to ~1000 j/kg CAPE or so per GEFS) should be present for general thunderstorms with severe threat on the low side as shear remains weak. Any storms should dissipate by sunset. High pressure system over much of central and western SD for Monday with the possibility of isolated (15-25%) afternoon showers and thunderstorms, mainly over eastern SD/western MN (behind the exiting low) and help from the embedded wave. Again just enough CAPE for general thunder as shear remains low. Another wave and surface trough look possible Tuesday, however, forecast remains dry for now. Otherwise into the midweek, the forecast looks quiet and dry. With the incoming ridge, temps will gradually warm up from west to east across the CWA next week, with temps back into the 80s Tuesday and Wednesday. Probability of 90 degrees and above Thursday is 25- 50% from north central to south central SD. For Friday, prob increases to 30-85% over this same area. NBM 25th-75th spread is not too bad ranging from 3-6 degrees next week. So depends on the speed eastward of the ridge and intensity, as mentioned earlier. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1223 AM CDT Sat Jul 6 2024 Terminals KABR,KATY,KPIR,KMBG Showers and thunderstorms will track across the area overnight into early Saturday morning. Additional shower and thunderstorm development is expected across the area Saturday afternoon and evening. For the most part, VFR conditions will prevail overnight and through the day Saturday, but there may be brief periods of MVFR vsbys with any thunderstorms that develop. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Parkin SHORT TERM...Serr LONG TERM...MMM AVIATION...Parkin