020  
FNUS73 KUNR 170036  
FWSUNR  
 
SPOT FORECAST FOR IDOL...SDS WILDLAND FIRE  
NATIONAL WEATHER SERVICE RAPID CITY SD  
636 PM MDT WED SEP 16 2026  
 
FORECAST IS BASED ON FORECAST START TIME OF 1900 MDT ON SEPTEMBER 16.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE.  
   
DISCUSSION  
NORTHERLY WINDS WILL DIMINISH OVER THE NEXT SEVERAL  
HOURS AND BECOME DOWNSLOPE/DOWNVALLEY FOR MUCH OF THE NIGHT. THE  
OVERNIGHT RH WILL RECOVER TO AROUND 75 PERCENT BY THURSDAY  
MORNING. CLOUDY CONDITIONS ARE EXPECTED THURSDAY WITH WETTING  
RAIN CHANCES 50/50 BY THURSDAY AFTERNOON. WINDS WILL REMAIN  
GENERALLY LIGHT THROUGH THE DAY. COOL AND WET CONDITIONS CONTINUE  
INTO THURSDAY NIGHT, BEFORE DRYING OUT ON FRIDAY. COOL AND WET  
CONDITIONS ARE EXPECTED AGAIN OVER THE WEEKEND.  
 
   
REST OF TONIGHT  
 
SKY/WEATHER.........PARTLY CLOUDY (20-30 PERCENT) THEN BECOMING  
MOSTLY CLOUDY (60-70 PERCENT).  
MIN TEMPERATURE.....AROUND 52.  
MAX HUMIDITY........75 PERCENT.  
WIND (20 FT)........NORTH WINDS 8 TO 14 MPH WITH GUSTS TO AROUND  
20 MPH BECOMING LIGHT DOWNSLOPE/DOWNVALLEY BY  
LATE THIS EVENING.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......500 TO 1000 FT AGL.  
TRANSPORT WINDS.....NORTHEAST 10 TO 15 MPH SHIFTING TO THE EAST  
OVERNIGHT.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........21 15 18 19 31 36 51 61 67 74 78  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0  
TEMP............70 66 63 61 58 55 55 54 54 53 52  
RH..............35 42 45 50 55 61 64 66 69 71 73  
20 FT WIND DIR..N NE NE NE E E E E E E E  
20 FT WIND SPD..5 3 2 2 2 2 1 1 1 1 1  
20 FT WIND GUST.14 12 10 9 8 8 7 7 7 7 7  
MIX HGT (KFT)...0.8 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5  
TRANSP WIND DIR.N NE NE NE NE E E E E E SE  
TRANSP WIND SPD.14 12 9 8 8 7 7 7 7 7 7  
   
THURSDAY  
 
SKY/WEATHER.........MOSTLY CLOUDY (80-90 PERCENT). ISOLATED  
RAIN SHOWERS AND THUNDERSTORMS BY LATE MORNING.  
RAIN SHOWERS LIKELY IN THE AFTERNOON.  
MAX TEMPERATURE.....AROUND 72.  
MIN HUMIDITY........55 PERCENT.  
WIND (20 FT)........LIGHT WINDS BECOMING UPSLOPE/UPVALLEY BY MID  
MORNING, THEN MAINLY OUT OF THE EAST TO  
SOUTHEAST AT 4 TO 8 MPH. GUSTY AND ERRATIC WINDS  
EXPECTED NEAR THUNDERSTORMS.  
CWR.................50 PERCENT.  
MIXING HEIGHT.......1800 TO 2300 FT AGL.  
TRANSPORT WINDS.....SOUTHEAST 10 TO 15 MPH.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........80 87 76 73 71 74 89 89 90 92 93 97  
WEATHER COV..... SCH SCH SCH CHC CHC CHC LKY LKY LKY  
WEATHER TYPE.... RW RW RW RW RW RW RW RW RW  
TSTM COV........ SCH SCH SCH SCH SCH SCH SCH SCH SCH  
CWR.............10 10 10 10 20 30 40 50 50 50 50 50  
TEMP............54 54 57 61 64 66 69 69 69 70 68 67  
RH..............71 69 67 62 58 56 55 59 59 59 63 68  
20 FT WIND DIR..E E E E E E SW W NE E SE SE  
20 FT WIND SPD..1 2 2 2 3 2 2 2 2 3 3 3  
20 FT WIND GUST.7 7 9 10 10 13 14 14 14 15 14 13  
MIX HGT (KFT)...0.5 0.5 0.5 0.9 1.2 1.8 2.3 1.6 1.7 1.8 1.5 1.2  
TRANSP WIND DIR.SE SE SE SE SE SE SE SE SE SE SE SE  
TRANSP WIND SPD.7 7 8 9 10 10 12 12 12 12 12 12  
   
THURSDAY NIGHT  
 
SKY/WEATHER.........MOSTLY CLOUDY (75-85 PERCENT). RAIN SHOWERS  
LIKELY IN THE EVENING, THEN CHANCE OF RAIN  
SHOWERS OVERNIGHT.  
MIN TEMPERATURE.....AROUND 55.  
MAX HUMIDITY........90 PERCENT.  
WIND (20 FT)........SOUTHEAST WINDS AROUND 5 MPH WITH GUSTS TO  
AROUND 10 MPH SHIFTING TO THE SOUTH EARLY IN  
THE MORNING.  
CWR.................50 PERCENT.  
MIXING HEIGHT.......500 TO 1000 FT AGL.  
TRANSPORT WINDS.....SOUTHEAST 10 TO 15 MPH SHIFTING TO THE  
SOUTHWEST OVERNIGHT.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........96 92 85 82 82 77 67 63 63 62 63 63  
WEATHER COV.....LKY LKY LKY LKY LKY LKY CHC CHC CHC CHC CHC CHC  
WEATHER TYPE....RW RW RW RW RW RW RW RW RW RW RW RW  
TSTM COV........SCH SCH SCH  
CWR.............50 50 50 50 50 50 50 50 50 50 50 50  
TEMP............65 62 60 60 59 59 58 58 59 57 57 57  
RH..............73 78 87 87 90 87 87 87 80 83 80 80  
20 FT WIND DIR..SE E E SE SE SE SE SE SE S S S  
20 FT WIND SPD..3 3 3 3 2 2 2 1 1 1 1 1  
20 FT WIND GUST.14 12 13 13 12 9 10 9 8 7 7 8  
MIX HGT (KFT)...1.0 0.8 0.7 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5  
TRANSP WIND DIR.E E SE SE SE SE SE SE S SW SW SW  
TRANSP WIND SPD.13 13 14 14 14 13 10 8 7 6 6 8  
 
 
FORECASTER...SR  
REQUESTED BY...LAURA STEE  
TYPE OF REQUEST...WILDFIRE  
.TAG 2622037.0/UNR  
.DELDT 09/16/26  
.FORMATTERVERSION 2.0.0  
.EMAIL SDGPC@FIRENET.GOV  
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