255  
FNUS73 KUNR 191531  
FWSUNR  
 
SPOT FORECAST FOR ROUTE FOUR NINE...SD-PRA  
NATIONAL WEATHER SERVICE RAPID CITY SD  
931 AM MDT TUE AUG 19 2025  
 
FORECAST IS BASED ON FORECAST START TIME OF 1000 MDT ON AUGUST 19.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE.  
   
DISCUSSION
 
 
HOT AND DRY CONDITIONS ARE EXPECTED TODAY AND TOMORROW, WITH HIGHS  
IN THE MID TO UPPER 90S AND MINIMUM RELATIVE HUMIDITY VALUES  
LIKELY FALLING BELOW 20 PERCENT. LIGHT AND VARIABLE WINDS EARLY  
TODAY WILL BECOME PREDOMINANTLY EASTERLY BY EARLY AFTERNOON, THEN  
SHIFT TO THE SOUTH THIS EVENING. WINDS WILL GRADUALLY INCREASE OVER  
THE NEXT 24 HOURS, WITH SUSTAINED WINDS OF 10 TO 15 MPH AND GUSTS  
TO 25 MPH EXPECTED TOMORROW AFTERNOON.  
   
REST OF TODAY
 
 
SKY/WEATHER.........SUNNY (5-15 PERCENT).  
MAX TEMPERATURE.....AROUND 95.  
MIN HUMIDITY........15 TO 20 PERCENT.  
WIND (20 FT)........LIGHT AND VARIABLE WINDS THIS MORNING BECOMING  
PREDOMINANTLY EAST AROUND 10 MPH BY EARLY  
AFTERNOON. GUSTS TO AROUND 15 MPH IN EXPOSED  
AREAS THIS AFTERNOON.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......10600 TO 11100 FT AGL INCREASING TO 11300 TO  
11800 FT AGL LATE IN THE AFTERNOON.  
TRANSPORT WINDS.....NORTHWEST TO NORTH AROUND 10 MPH THIS MORNING  
BECOMING EAST AT 10 TO 15 MPH BY EARLY  
AFTERNOON.  
SMOKE DISPERSAL.....GOOD INCREASING TO EXCELLENT LATE IN THE  
AFTERNOON.  
 
TIME (MDT) 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........2 3 3 5 8 10 12 14  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0  
TEMP............83 85 91 93 93 95 95 94  
RH..............36 32 27 23 22 19 19 21  
20 FT WIND DIR..S E E E E E E E  
20 FT WIND SPD..5 5 6 7 8 9 10 10  
20 FT WIND GUST.9 9 10 13 14 15 16 17  
MIX HGT (KFT)...1.7 3.1 6.5 9.6 11 12 12 10  
TRANSP WIND DIR.NW N NE NE E E E E  
TRANSP WIND SPD.8 9 10 12 14 15 16 17  
   
TONIGHT
 
 
SKY/WEATHER.........MOSTLY CLEAR (10-20 PERCENT).  
MIN TEMPERATURE.....AROUND 65.  
MAX HUMIDITY........85 TO 90 PERCENT.  
WIND (20 FT)........EAST WINDS AROUND 10 MPH SHIFTING TO THE SOUTH  
OVERNIGHT. GUSTS UP TO 20 MPH.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......400 TO 900 FT AGL.  
TRANSPORT WINDS.....EAST AT 15 TO 20 MPH SHIFTING TO THE SOUTH LATE  
IN THE EVENING.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........16 21 26 17 10 8 6 7 7 7 8 11  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............91 87 82 78 76 74 72 71 70 67 66 66  
RH..............25 30 40 47 52 57 64 68 68 78 84 81  
20 FT WIND DIR..E E E E SE SE SE S S S S S  
20 FT WIND SPD..10 10 10 10 10 10 10 10 10 10 10 9  
20 FT WIND GUST.17 17 18 18 18 18 18 17 17 16 16 16  
MIX HGT (KFT)...6.2 0.9 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.4 0.4  
TRANSP WIND DIR.E E E E E SE SE S S S S S  
TRANSP WIND SPD.18 18 18 18 18 18 17 17 16 16 15 15  
   
WEDNESDAY
 
 
SKY/WEATHER.........SUNNY (0-10 PERCENT).  
MAX TEMPERATURE.....AROUND 97.  
MIN HUMIDITY........AROUND 20 PERCENT.  
WIND (20 FT)........SOUTH WINDS 10 TO 15 MPH WITH GUSTS TO AROUND  
25 MPH.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......8900 TO 9400 FT AGL INCREASING TO 10400 TO  
10900 FT AGL LATE IN THE AFTERNOON.  
TRANSPORT WINDS.....SOUTH 15 TO 25 MPH.  
SMOKE DISPERSAL.....GOOD INCREASING TO EXCELLENT IN THE AFTERNOON.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........14 11 3 1 0 1 1 3 4 6 7 8  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............64 67 71 79 84 89 92 94 96 96 96 95  
RH..............87 81 71 56 44 35 30 26 23 21 20 21  
20 FT WIND DIR..S S S S S S S S S S S SE  
20 FT WIND SPD..9 10 12 12 13 13 14 14 14 14 14 14  
20 FT WIND GUST.16 16 17 18 20 20 21 22 22 23 23 23  
MIX HGT (KFT)...0.4 0.6 0.8 1.1 2.8 4.5 6.3 7.8 9.4 11 9.8 8.7  
TRANSP WIND DIR.S S S S S S S S SE SE SE SE  
TRANSP WIND SPD.15 16 17 18 18 20 21 22 22 22 22 22  
 

 
FORECASTER...KS  
REQUESTED BY...JUSTIN BAUER  
TYPE OF REQUEST...WILDFIRE  
.TAG 2519978.3/UNR  
.DELDT 08/19/25  
.FORMATTERVERSION 2.0.0  
.EMAIL JUSTIN.BAUER@BIA.GOV  
 
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