353  
FNUS73 KUNR 171400  
FWSUNR  
 
SPOT FORECAST FOR CLAY SPUR RX PREP...USDA FOREST SERVICE  
NATIONAL WEATHER SERVICE RAPID CITY SD  
800 AM MDT TUE JUN 17 2025  
 
FORECAST IS BASED ON IGNITION TIME OF 0700 MDT ON JUNE 17.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE.  
 
DISCUSSION...  
A SHOWER OR THUNDERSTORM IS POSSIBLE THIS MORNING, BUT THE MOST  
LIKELY TIME FOR SHOWERS AND THUNDERSTORMS IS 100 PM TO 600 PM,  
TAPERING OFF THIS EVENING AND ESPECIALLY AFTER SUNSET. ANY  
THUNDERSTORM COULD CONTAIN HAIL OR GUSTY ERRATIC WINDS AS THERE IS  
A MARGINAL RISK (1 OUT OF 5) OF SEVERE THUNDERSTORMS. MUCH WARMER  
AND MOSTLY DRY WEATHER WILL THEN PREVAIL THROUGH SATURDAY -  
ALTHOUGH A STRAY THUNDERSTORM CANNOT BE COMPLETELY RULED OUT, THE  
CHANCE IS LESS THAN 15%. THE NEXT ORGANIZED CHANCE OF  
THUNDERSTORMS SHOULD OCCUR SUNDAY NIGHT INTO EARLY NEXT WEEK.  
   
TODAY  
 
SKY/WEATHER.........MOSTLY CLOUDY (65-75 PERCENT). CHANCE OF RAIN  
SHOWERS AND SLIGHT CHANCE OF THUNDERSTORMS IN  
THE MORNING, THEN SHOWERS AND THUNDERSTORMS  
LIKELY IN THE AFTERNOON.  
MAX TEMPERATURE.....AROUND 69.  
MIN HUMIDITY........56 PERCENT.  
WIND (20 FT)........EAST WINDS 5-15 MPH BECOME NORTH.  
GUSTY AND ERRATIC  
WINDS EXPECTED NEAR THUNDERSTORMS.  
CWR.................45 PERCENT.  
MIXING HEIGHT.......4700 TO 5200 FT AGL.  
TRANSPORT WINDS.....NORTH 10 TO 15 MPH.  
SMOKE DISPERSAL.....FAIR.  
 
TIME (MDT) 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........67 66 64 68 71 75 74 73 73 73 73  
WEATHER COV.....CHC CHC CHC CHC CHC LKY LKY LKY LKY LKY LKY  
WEATHER TYPE....RW RW RW RW RW RW RW RW RW RW RW  
TSTM COV........SCH SCH SCH SCH SCH LKY LKY LKY LKY LKY LKY  
CWR.............40 40 40 40 40 40 40 40 40 40 40  
TEMP............56 57 59 61 63 65 67 68 69 68 68  
RH..............82 80 72 67 64 62 60 59 56 58 59  
20 FT WIND DIR..E N N N N N N N NE NE N  
20 FT WIND SPD..3 3 5 6 7 7 7 7 7 7 7  
20 FT WIND GUST.7 8 9 10 10 10 10 12 13 13 13  
MIX HGT (KFT)...1.1 1.6 2.2 2.5 2.9 3.3 3.9 4.4 5.2 3.9 3.1  
TRANSP WIND DIR.N N N N N N N N N N N  
TRANSP WIND SPD.9 9 9 10 10 10 10 12 12 12 12  
   
TONIGHT  
 
SKY/WEATHER.........MOSTLY CLOUDY (60-70 PERCENT) THEN BECOMING  
PARTLY CLOUDY (25-35 PERCENT). CHANCE OF  
SHOWERS AND THUNDERSTORMS EARLY IN THE EVENING.  
MIN TEMPERATURE.....AROUND 49.  
MAX HUMIDITY........100 PERCENT.  
WIND (20 FT)........NORTHEAST WINDS 5-10 MPH.  
GUSTY AND ERRATIC WINDS EXPECTED NEAR  
THUNDERSTORMS EARLY IN THE EVENING.  
CWR.................30 PERCENT.  
MIXING HEIGHT.......500 TO 1000 FT AGL.  
TRANSPORT WINDS.....NORTH AROUND 15 MPH SHIFTING TO THE NORTHEAST 5  
TO 15 MPH IN THE LATE EVENING AND OVERNIGHT.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........74 67 60 53 44 35 26 24 22 20 23 26  
WEATHER COV.....CHC CHC CHC  
WEATHER TYPE....RW RW RW  
TSTM COV........CHC CHC CHC  
CWR.............30 30 30 30 30 30 30 30 30 30 30 30  
TEMP............66 63 61 58 55 54 54 53 52 51 50 50  
RH..............62 69 78 80 88 88 90 90 93 97 100 98  
20 FT WIND DIR..N N NE N NE NE NE NE NE NE NE NE  
20 FT WIND SPD..7 6 5 5 3 2 2 2 2 2 2 2  
20 FT WIND GUST.12 9 9 8 7 7 3 6 6 6 5 6  
MIX HGT (KFT)...2.6 2.2 1.1 0.8 0.7 0.6 0.6 0.6 0.6 0.5 0.5 0.5  
TRANSP WIND DIR.N N N NE NE NE NE NE NE NE NE NE  
TRANSP WIND SPD.12 13 13 14 10 7 5 5 6 7 7 7  
   
WEDNESDAY  
 
SKY/WEATHER.........SUNNY (15-25 PERCENT).  
MAX TEMPERATURE.....AROUND 81.  
MIN HUMIDITY........28 PERCENT.  
WIND (20 FT)........LIGHT EAST WINDS BECOMING SOUTHWEST  
5-15 MPH IN THE AFTERNOON.  
CWR.................0 PERCENT.  
MIXING HEIGHT.......10000 TO 10500 FT AGL.  
TRANSPORT WINDS.....NORTHEAST AROUND 10 MPH SHIFTING TO THE SOUTH  
EARLY IN THE MORNING, THEN SHIFTING TO THE WEST  
LATE IN THE MORNING INCREASING TO 10 TO 15 MPH  
IN THE AFTERNOON.  
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 (%).........29 24 19 14 11 8 6 8 10 12 10 9  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............51 53 57 61 64 67 70 73 76 79 80 80  
RH..............94 92 83 73 65 56 49 42 35 32 29 28  
20 FT WIND DIR..NE E SE SW SW SW SW W W W SW S  
20 FT WIND SPD..2 2 2 3 5 5 6 6 6 6 5 5  
20 FT WIND GUST.6 6 6 6 7 9 10 12 13 13 13 13  
MIX HGT (KFT)...0.6 1.0 1.4 1.8 2.9 4.0 5.1 6.9 8.7 11 9.9 9.2  
TRANSP WIND DIR.NE E S SW SW W NW W W W W W  
TRANSP WIND SPD.6 6 6 6 7 8 9 12 13 14 14 13  
 
 
FORECASTER...EH  
REQUESTED BY...BLAKE COBB  
TYPE OF REQUEST...PRESCRIBED  
.TAG 2516107.0/UNR  
.DELDT 06/17/25  
.FORMATTERVERSION 2.0.0  
.EMAIL BLAKE.COBB@USDA.GOV  
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