970  
FNUS73 KUNR 201154  
FWSUNR  
 
SPOT FORECAST FOR WEST COAL CREEK FIRE...CAMPBELL COUNTY FIRE DEPARTMENT  
NATIONAL WEATHER SERVICE RAPID CITY SD  
554 AM MDT THU AUG 20 2026  
 
FORECAST IS BASED ON FORECAST START TIME OF 0600 MDT ON AUGUST 20.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE.  
   
DISCUSSION
 
LIGHT AND VARIABLE WINDS TODAY WILL TURN NORTHWESTERLY  
AFTER 1000-1100 THIS MORNING. WHILE SUSTAINED WINDS WILL BE LIGHT  
(LESS THAN 10 MPH) WITH GUSTS TO 15 MPH, THERE IS POTENTIAL FOR AN  
OCCASIONAL GUST TO 25 MPH DURING THE AFTERNOON (1400-1800) GIVEN  
HIGH MIXING HEIGHTS DURING PEAK HEATING. DAYTIME MINIMUM RELATIVE  
HUMIDITY WILL FALL TO AROUND 12 PERCENT WITH TEMPERATURES PUSHING  
INTO THE LOW TO MID 90S. EXPECT ELEVATED FIRE WEATHER CONDITIONS  
THIS AFTERNOON GIVEN HIGH TEMPERATURES AND LOW RH.  
 
OVERNIGHT RH RECOVERY WILL BE POOR (~50%) THURSDAY NIGHT INTO  
FRIDAY MORNING, ALTHOUGH WINDS WILL BE LIGHT AND VARIABLE.  
 
ELEVATED FIRE WEATHER CONDITIONS PERSIST FRIDAY WITH TEMPERATURES  
IN THE 90S, RH IN THE TEENS, AND NORTH WINDS WITH GUSTS 20 TO 25  
MPH DURING THE AFTERNOON.  
   
TODAY
 
 
SKY/WEATHER.........SUNNY (10-20 PERCENT).  
MAX TEMPERATURE.....AROUND 93.  
MIN HUMIDITY........12-15 PERCENT.  
WIND (20 FT)........LIGHT AND VARIABLE WINDS BECOMING NORTHWEST  
AFTER 1000-1100. SUSTAINED WINDS 5 TO 10 MPH  
WITH GUSTS TO 15 MPH. AN OCCASIONAL GUST TO  
25 MPH IS POSSIBLE BETWEEN 1400 AND 1800.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......9100 TO 9600 FT AGL INCREASING TO 10200 TO  
10700 FT AGL LATE IN THE AFTERNOON.  
TRANSPORT WINDS.....SOUTHWEST AROUND 10 MPH SHIFTING TO THE  
NORTHWEST LATE IN THE MORNING.  
SMOKE DISPERSAL.....GOOD INCREASING TO VERY GOOD LATE IN THE  
AFTERNOON.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........11 23 10 6 4 4 6 7 6 6 6 3  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............55 58 64 71 77 82 87 89 91 93 93 93  
RH..............46 49 41 33 27 22 19 17 14 13 13 13  
20 FT WIND DIR..S SW SW W W NW NW NW NW NW NW N  
20 FT WIND SPD..5 2 2 2 2 3 3 3 3 3 5 5  
20 FT WIND GUST.7 6 7 8 8 8 10 12 14 14 15 14  
MIX HGT (KFT)...0.5 0.4 0.4 0.7 2.4 5.4 7.5 8.7 9.6 11 10 10  
TRANSP WIND DIR.S SW SW SW W W W W W W NW NW  
TRANSP WIND SPD.7 8 8 8 8 8 8 9 12 13 13 12  
   
TONIGHT
 
 
SKY/WEATHER.........PARTLY CLOUDY (45-55 PERCENT).  
MIN TEMPERATURE.....AROUND 63.  
MAX HUMIDITY........50 PERCENT.  
WIND (20 FT)........NORTH-NORTHWEST WINDS BECOMING LIGHT AND  
VARIABLE OVERNIGHT; SUSTAINED WINDS AROUND  
5 MPH.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......400 TO 900 FT AGL.  
TRANSPORT WINDS.....NORTHWEST AROUND 15 MPH SHIFTING TO THE EAST  
EARLY IN THE EVENING, THEN SHIFTING TO THE  
SOUTHEAST LATE IN THE EVENING SHIFTING TO THE  
SOUTH AFTER 3 AM.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........5 11 26 43 49 58 50 55 60 60 63 58  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............92 89 84 79 75 73 71 69 67 66 64 63  
RH..............14 17 20 25 28 31 35 39 42 43 46 50  
20 FT WIND DIR..N N NE E E E SE SE S S S S  
20 FT WIND SPD..5 3 3 3 3 5 3 3 3 3 5 5  
20 FT WIND GUST.14 12 10 12 13 10 10 9 10 10 10 9  
MIX HGT (KFT)...8.9 3.4 0.4 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.4 0.4  
TRANSP WIND DIR.NW N NE E E SE SE SE S S S S  
TRANSP WIND SPD.12 12 12 13 13 14 14 15 15 15 15 13  
 

 
FORECASTER...SE  
REQUESTED BY...TRAVIS WICKWIRE  
TYPE OF REQUEST...WILDFIRE  
.TAG 2620074.0/UNR  
.DELDT 08/20/26  
.FORMATTERVERSION 2.0.0  
.EMAIL BRYANB@CAMPBELLCOFIREWY.US,TRAVISW@CAMPBELLCOFIREWY.GOV  
 
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