Area Forecast Discussion
Issued by NWS Aberdeen, SD
Issued by NWS Aberdeen, SD
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323 FXUS63 KABR 311523 AAA AFDABR Area Forecast Discussion...UPDATED National Weather Service Aberdeen SD 1023 AM CDT Fri May 31 2024 .KEY MESSAGES... - There is a 50-80% chance for showers and thunderstorms Sunday afternoon and evening. Strong to severe thunderstorms will be possible. - Temperatures are forecast to rise above normal this weekend into next week (highs in the 80s). && .UPDATE... Issued at 1015 AM CDT Fri May 31 2024 Radar trends continue to show general rain showers over parts of southwest/south central South Dakota working their way northeast. The forecast/POPs reflect this well in the forecast for now. Will continue to monitor and adjust as necessary. No other changes made to the forecast this morning. && .SHORT TERM /TODAY THROUGH SATURDAY AFTERNOON/... Issued at 328 AM CDT Fri May 31 2024 The surface weather map at 08Z showed the exiting cold front/trough across western MN and far southeastern SD. High pressure was set up over much of western and central SD. While more persistent fog has been seen off satellite imagery northeast of Traverse County in MN, spotty fog has developed over eastern SD. This is where more rain has fallen over the past 18 hours adding to the low level moisture, and where winds remain light. A new daily record for precipitation was reached yesterday at K8D3/Sisseton, with 1.35". We will keep monitoring the latest visibility trends, like KATY/Watertown varying between greater than 6 miles and 1/4 mile visibility between 0645- 0745Z. Despite the area of high pressure at the surface, much of western SD is under clouds and light rain. This is thanks in part to the 500mb trough moving across the Northern Plains into Saturday morning. We will continue the chance of light rain (around 20% chance) across portions of the area through the day mainly from around Pierre northeast to Redfield, Sisseton, and Watertown. These low chances for precipitation will continue into this evening, before dry weather returns through Saturday morning. Relatively light winds will remain through the period. && .LONG TERM /SATURDAY EVENING THROUGH THURSDAY/... Issued at 328 AM CDT Fri May 31 2024 Saturday evening starts the long term with westerly flow aloft. This will remain the pattern through Monday night. Tuesday, we get into some southerly flow as a negatively tilted trough starts to move in from the west. The GFS brings that trough in a bit faster than the Canadian and EC, with the axis of the trough passing over the area during the day Tuesday. The other two deterministic models are slower and also bring the center of the low over the region overnight Tuesday through Wednesday. The EC keeps the low circulating over the Dakotas through the night Wednesday before slowly moving southeast Thursday. The EC definitely has a stronger and slower low, with shortwave energy remaining over eastern SD into Friday morning. The Canadian and GFS both have northwesterly upper level flow after the low moves off through the end of the period. The best chance for some rain looks to be Sunday evening into early Monday morning. NBM has PoPs ranging from 25% across central SD to 65% over northeastern SD Sunday evening and 15-25% west river to 75- 80% east of the James River Sunday night. With mid level lapse rates around 7.5 C/km over eastern SD and MLCAPE between 1000 and 2000 J/kg, there looks to be a good probability of storms east of the Missouri River with some possibly becoming severe. SPC has placed the area in a slight risk (2 of 5) for severe storms already at Day 3. Another chance for rain would be Tuesday evening. NBM has PoPs in the 25-45% range for areas east of the Missouri River. There also looks to be a chance for some severe storms during this time frame around and east of the James River with LR and CAPE values about the same as Sunday evening. With southerly winds and WAA, high temperatures for the first few days of the period will be between 5 and 10 degrees above average, in the upper 70s to low 80s. When the low moves in mid-week, winds will be more northerly and bring CAA, which will bring temperatures down to about average. Winds on Tuesday and Wednesday could become strong during the afternoon hours mainly west river, with gusts of 30-35 mph possible. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 622 AM CDT Fri May 31 2024 Terminals KABR,KATY,KPIR,KMBG VFR conditions are expected to continue. While we did have fog at ATY, much have that has gone away after sunrise and with the higher clouds moving in. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. && $$ UPDATE...Serr SHORT TERM...KF LONG TERM...KK AVIATION...KF