FXUS63 KUNR 062333

AFDUNR



Area Forecast Discussion For Western SD and Northeastern WY

National Weather Service Rapid City SD

533 PM MDT Wed May 6 2026



.KEY MESSAGES...



- Warming trend as we move towards the weekend.



- Active northwest flow will bring chances for showers/storms,

  mainly Thursday and Saturday.



&&



.DISCUSSION...(This Evening Through Wednesday)

Issued at 1213 PM MDT Wed May 6 2026



Current Water Vapor and upper air models show northwest flow over

the FA, as weak troughing sits over the Great Lakes region and

upper ridge builds over the far western CONUS. 18Z Surface

analysis has high pressure centered over eastern Wyoming this

afternoon. Satellite shows some low-top CU development over the

forecast area. Temperatures currently sit in the 40s and low 50s

over the region, with winds out of the northwest. 



Upper ridge builds over the Rockies tonight and Thursday,

resulting in warmer temperatures for the area. Highs Thursday will

be in the upper 50s and 60s, while Friday will see widespread 70s.

Main concern for Thursday will be the potential for showers/storms

as a shortwave rides the northwest flow through the CWA.  

The better forcing region for precipitation potential looks to be

from northeastern WY into the Black Hills and southwestern SD. Low

CAPE values (200-400 j/Kg) and some low eff shear will be enough

to spark some thunderstorms in the showery regions. Given the 

forecast thermal profiles, not expecting any severe storm 

potential, but some gusty winds 40-50mph may be possible near 

showers/storms. 



Dry conditions return Friday, but precipitation chances return

Saturday as a weak wave moves thorugh WY into SD/NE. Upper ridge

slides over the Rockies into the northern and central plains early

next week, resulting in continued warmer temperatures and mostly

dry conditions Sunday through middle of next week. 



&&



.AVIATION...(For the 00Z TAFS Through 00Z Thursday Evening)

Issued At 523 PM MDT Wed May 6 2026



VFR conditions prevail this evening and overnight. Scattered rain

showers and isolated thunderstorms are expected to develop midday

Thursday, beginning over northeast Wyoming around 17Z and 

reaching southwestern South Dakota by 19Z. MVFR/IFR visibility and

gusty, erratic winds may be present near thunderstorms. Showers 

and isolated storms will persist through the remainder of the TAF

period.



&&



.UNR WATCHES/WARNINGS/ADVISORIES...

SD...None.

WY...None.

&&



$$



DISCUSSION/KEY MESSAGES...Dye

AVIATION...Schultz