FXUS63 KUNR 091925
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
125 PM MDT Thu Jul 9 2026

.KEY MESSAGES...

-Another round of passing storms is likely this afternoon and
 evening for northeast Wyoming and far western and southwestern
 South Dakota.

-Sufficient moisture and shear is in place to support a few 
 strong to severe storms.

-Very hot this weekend into early next week with record high 
 temps possible and dangerous heat.

&&

.DISCUSSION...(This Evening Through Thursday)
Issued at 104 PM MDT Thu Jul 9 2026

Latest satellite imagery and radar show mostly clear to clear 
skies for most of the area. The big exception is the Black Hills 
and northeast Wyoming, where clouds and a few storm cells have 
bubbled up in the heat of the day. As of this writing, 1 PM, these
storms haven’t lasted long and fade out quickly after maturing.

For the rest of this afternoon through tonight, storms will 
continue to develop through the afternoon and track east then 
southeast through the evening. Some of these storms have the 
potential to be severe with the main concern being hail and a 
secondary concern for strong wind gusts. Overnight though should 
be quiet with light winds and overnight temps dropping to the 
upper 50s to lower 60s.

For Friday, an upper level high pressure will build and start to 
shift northward. This will bring a warming trend to the area. 
Afternoon temps on Friday will reach the 90s for most of the area.
Low end chances for short lived, afternoon storms in the Black 
Hills.

The weekend is looking hot with highs at or above 100F for both 
Saturday and Sunday. Morning temps will be in the 60s to near 70. 
An Extreme Heat Watch has been issued due to heat index values 
above 100 degrees for multiple days in a row. With the hot 
temperatures and low dew points, humidities will be low so fire 
weather conditions will be elevated. 

For a quick look at next week, the hot weather will continue
through mid week. A potential pattern change would give cooler,
but still warmer than normal, temperatures later in the week. As
the pattern changes, thunderstorms would be possible.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Friday)
Issued At 1125 AM MDT Thu Jul 9 2026

Another round of convection is expected today, primarily over the
Black Hills and areas east. A PROB30 has been included for KRAP,
thunderstorms will be capable of large hail and gusty winds.
MVFR/IFR conditions are possible near/under stronger storms. 12Z
suite of CAMs had little confidence areas of northeastern WY near
KGCC would be impacted by TS, so it was left out. Will be closely
monitoring the development of storms today in case the surface
boundary slows and pops storms further west than anticipated.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Extreme Heat Watch from Saturday afternoon through Monday 
     evening for SDZ001-002-012>014-025>027-029>032-041>043-046-
     072>075-077-078.
WY...Extreme Heat Watch from Saturday afternoon through Monday 
     evening for WYZ054>056-058>060.
&&

$$

DISCUSSION...GS
AVIATION...Schweigert