789 FXUS63 KABR 040111 AAB AFDABRArea Forecast Discussion...UPDATED National Weather Service Aberdeen SD 811 PM CDT Fri Oct 3 2025
.KEY MESSAGES...
- Near record high temperatures will remain possible east of a line from Pierre to Ipswich on Saturday, where highs will be in the mid 80s to near 90 degrees.
- Windy conditions Saturday and Saturday night will be east of a line from Vivian to Aberdeen, where winds out of the south will gust 30 to 40 mph. On Sunday the winds will be switching out of the northwest, with gusts of 35 to 45 mph with locally higher gusts.
- A cold front will bring rain Saturday night through Sunday morning. There is a Marginal Risk, level 1 of 5, for severe storms Saturday night. Damaging winds will be the main concern. Heavy rain or hail will also be possible.
- There is a slight shift westwards with the highest rainfall potential. There is a 50 to 75% chance of rain in excess of 1" along and west of a line from Mobridge to Hayes.
- Localized frost is possible Monday morning, Tuesday morning, and Wednesday morning, mainly over portions of northern SD.
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.UPDATE... Issued at 806 PM CDT Fri Oct 3 2025
Red Flag warning was allowed to expire at 01Z as RH increases and winds slowly subside. Otherwise, forecast remains on track overnight with breezy/gusty southerly winds persisting especially for eastern portions of the CWA. Localized gusts in the Sisseton Hills region from 30 to 45 mph.
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.DISCUSSION... Issued at 300 PM CDT Fri Oct 3 2025
Winds will remain the main story through Sunday, with gusty winds not only during the daytime hours but at night as well. Fire weather wise, the near-critical areas with less green component in grasses is west of the Missouri River. Elsewhere there is green in the ditches and other grasses, but any farm land is dry (soybeans/corn). These crops would be the main carrier of any fire that may start over the next few days. With the continued lowering/western shift in the the overall precipitation amounts for Saturday night into Sunday morning, winds and fire weather will continue to be the main concerns.
Looking at the 19Z surface map, the main low was centered over southeastern MT/southwestern NE/northwestern SD, with plenty of clouds on the northern and western side of the low. Out ahead, winds were out of the south gusting 25-45 mph (strongest just west of Jones County). The lowest relative humidity values around 20-30 percent were over south central SD, with teens over southwestern SD.
This main surface low will shift across northern ND by 06Z Saturday, with a cold front extending south-southwest over Corson County through southwestern SD. Strong winds today out of the south will only slowly weaken overnight, but remain elevated over the Prairie Coteau of northeastern South Dakota, with gusts of 35 to 45 mph from eastern Marshall County down through Summit and South Shore. Relative humidity recoveries will be around 75 percent or higher, except closer to 65 percent over the eastern slopes of the Prairie Coteau.
A series of lows will slide northeast along the cold front as it shifts over mainly central SD by 00Z Sunday. The surface low overhead will continue to deepen as it moves over our north central forecast area by 06Z and southeastern SD into northwestern MN by 12Z Sunday. Expect windy conditions east of a line from Vivian to Aberdeen Saturday and Saturday night, out of the south will gusts 30 to 40 mph. This is where lowest relative humidity values of 25 to 35 percent will reside.
A Downslope wind event is possible Saturday night over the traditional locations from eastern Marshall through western/central Roberts (Summit/Peever) and northeastern Codington to western Grant through northern Deuel County. Winds between 800-900mb are 60-65kts with mixing, with a localized mixed environment and gusts of 45- 50kts for a good portion of the night. A wind headline may be needed.
Rain is also expected Saturday night into Sunday morning, but the higher amounts have again shifted to the west. A wetting rain of 0.10 inches or greater is expected northwest of a line from Pierre to Aberdeen. The probability of 0.25" or more in that same area is 25% or greater. The probability of 1" or more is 45% or greater northwest of a line from around Eagle Butte through Mobridge and Herreid. Little to no rain is forecast over west central MN and east central SD.
On Sunday the winds will be switching out of the northwest, with gusts of 35 to 45 mph and locally higher gusts. While relative humidity values will stay above 70 percent for most locations west of the James River, they will be as low as 50 percent over portions of west central MN and east central SD.
High pressure over southwestern Canada/MT on Sunday will build across SD on Monday, ushering in drier air and much cooler air. Highs Monday will be in the mid 50s to low 60s. Confidence remains high in the temperature forecast through Monday, before the 25-75th percentiles spread out a bit Monday night. Temperatures will moderate back into the 70s for highs by the end of the work week. We do still have the potential for frost each morning from Monday morning, Tuesday morning, and Wednesday morning. The overall coverage looks limited at this time, and focused over norther portions of SD.
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.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 635 PM CDT Fri Oct 3 2025
Terminals KABR,KATY,KPIR,KMBG
Low-level wind shear (LLWS) will be a concern across the region overnight, with winds from 40 to 50 knots out of the south- southwest around 2000ft. Otherwise, expect VFR conditions with gusty southerly surface winds continuing across KABR/KATY. Across KMBG/KPIR, winds will gradually switch to the west and north behind a frontal boundary.
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.ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. &&
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UPDATE...TMT DISCUSSION...06 AVIATION...TMT
NWS ABR Office Area Forecast Discussion