630
FNUS73 KUNR 180327 CCA
FWSUNR
SPOT FORECAST FOR GREYHOUND FIRE...CORRECTED
NATIONAL WEATHER SERVICE RAPID CITY SD
827 PM MST WED DEC 17 2025
FORECAST IS BASED ON FORECAST START TIME OF 2000 MST ON DECEMBER 17.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE.
..HIGH WIND WARNING IN EFFECT UNTIL 8 AM MST THURSDAY
DISCUSSION
IT LOOKS LIKE WINDS HAVE DIED DOWN FOR SHELTERED
AREAS BASED ON NEARBY OBSERVATIONS AROUND 8PM, BUT SUSPECT
RIDGETOPS ARE STILL GUSTING OVER 40 MPH. MIXED RAIN AND SNOW
SHOULD END BY 9PM. WETTING PRECIPITATION IS UNLIKELY.
A STRONGER COLD FRONT WILL ARRIVE AROUND 2AM EARLY THURSDAY
MORNING WITH INCREASED NORTHWEST WINDS AT 20-40 MPH AND GUSTS
INCREASING TO 50-60 MPH THROUGH 8AM THURSDAY. WINDS WILL THEN
DIMINISH QUICKLY AFTER 8AM. BY MIDDAY, NORTHWEST WINDS WILL BLOW
AT 15-20 MPH WITH GUSTS OF 30-40 MPH. AFTER 3PM, WINDS WILL BECOME
WEST TO SOUTHWEST AT 10-20 MPH.
GOOD RELATIVE HUMIDITY RECOVERY (76%) IS EXPECTED TONIGHT WITH
LOWS IN THE LOWER 20S. MINIMUM RELATIVE HUMIDITIES ON THURSDAY
WILL DROP TO 32% WITH HIGH TEMPERATURES AROUND 34 DEGREES. AFTER
TEMPERATURES BOTTOM OUT THURSDAY EVENING IN THE MID 20S,
TEMPERATURES WILL RISE OVERNIGHT THURSDAY WITH UNSEASONABLY WARM
TEMPERATURES FOR FRIDAY WITH HIGHS IN THE UPPER 50S AND MINIMUM
RELATIVE HUMIDITIES DROPPING TO 29%.
REST OF TONIGHT
SKY/WEATHER.........BECOMING PARTLY CLOUDY (30-40 PERCENT).
MIXED RAIN/SNOW ENDING BY 9PM.
MIN TEMPERATURE.....AROUND 22.
MAX HUMIDITY........76 PERCENT.
WIND (20 FT)........WINDY. NORTHWEST WINDS 10-20 MPH GUSTING TO
40 MPH BEFORE 2AM. THEN, NORTHWEST WINDS
20-40 MPH WITH GUSTS INCREASING TO 50-60 MPH.
CWR.................25 PERCENT.
MIXING HEIGHT.......1300 TO 1800 FT AGL.
TRANSPORT WINDS.....NORTHWEST 70 TO 75 MPH INCREASING TO 90 TO 95
MPH.
SMOKE DISPERSAL.....GOOD.
TIME (MST) 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........39 34 33 25 26 31 32 33 37 46
WEATHER COV.....LKY
WEATHER TYPE....SN
TSTM COV........
CWR.............20 20 20 20 20 20 20 20 20 20
TEMP............37 35 34 33 31 29 28 26 25 23
RH..............57 58 53 54 52 48 44 47 48 52
20 FT WIND DIR..NW NW W W W NW NW NW NW NW
20 FT WIND SPD..20 20 20 20 20 25 32 35 36 36
20 FT WIND GUST.40 40 40 40 40 53 55 58 60 62
MIX HGT (KFT)...1.3 2.1 1.9 2.1 2.2 1.9 1.8 1.8 1.7 2.0
TRANSP WIND DIR.NW NW W W W W NW NW NW NW
TRANSP WIND SPD.66 69 71 74 78 82 86 90 92 92
THURSDAY
SKY/WEATHER.........MOSTLY SUNNY (35-45 PERCENT).
MAX TEMPERATURE.....AROUND 34.
MIN HUMIDITY........32 PERCENT.
WIND (20 FT)........WINDY. NORTHWEST WINDS 30 TO 35 MPH WITH GUSTS
AROUND 60 MPH QUICKLY DECREASING TO 15 TO 25 MPH
AS THEY BECOME WEST/SOUTHWEST FOR THE AFTERNOON.
CWR.................0 PERCENT.
MIXING HEIGHT.......3400 TO 3900 FT AGL.
TRANSPORT WINDS.....NORTHWEST 85 TO 90 MPH DECREASING TO 75 TO 80
MPH EARLY IN THE MORNING, THEN DECREASING TO
10-25 MPH IN THE AFTERNOON AS THEY BECOME WEST.
SMOKE DISPERSAL.....EXCELLENT DECREASING TO GOOD LATE IN THE
AFTERNOON.
TIME (MST) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........44 41 40 25 24 15 19 27 34 42 52 63
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............23 24 24 26 28 30 32 34 34 34 33 30
RH..............50 47 49 46 43 39 35 32 33 33 36 42
20 FT WIND DIR..NW NW NW NW NW NW NW NW NW W W SW
20 FT WIND SPD..35 33 30 26 23 20 17 15 13 12 9 7
20 FT WIND GUST.61 56 52 49 46 40 37 32 28 22 16 10
MIX HGT (KFT)...1.9 2.0 2.3 2.8 2.8 3.0 3.3 3.6 3.9 2.8 1.7 0.5
TRANSP WIND DIR.NW NW NW NW NW NW NW NW NW W SW S
TRANSP WIND SPD.90 85 79 73 66 58 49 43 35 25 16 10
THURSDAY NIGHT
SKY/WEATHER.........MOSTLY CLOUDY (60-80 PERCENT).
MIN TEMPERATURE.....AROUND 24.
MAX HUMIDITY........53 PERCENT.
WIND (20 FT)........SOUTH WINDS AROUND 10 MPH IN THE EVENING, THEN
INCREASING TO SOUTHWEST AT 12-25 MPH LATE WITH
HIGHER GUSTS.
CWR.................0 PERCENT.
MIXING HEIGHT.......400 TO 900 FT AGL.
TRANSPORT WINDS.....SOUTH 10 TO 20 MPH INCREASING TO SOUTHWEST 20
TO 30 MPH OVERNIGHT, THEN SHIFTING TO THE WEST
30 TO 35 MPH AFTER 3 AM.
SMOKE DISPERSAL.....POOR.
TIME (MST) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........73 47 67 61 70 79 73 66 60 57 53 50
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............28 27 25 26 27 27 29 31 33 36 39 42
RH..............46 48 53 50 48 48 48 48 49 50 49 47
20 FT WIND DIR..S S S S S S SW SW SW SW W W
20 FT WIND SPD..6 3 5 6 6 7 8 9 10 13 14 16
20 FT WIND GUST.8 10 14 16 18 21 23 25 29 32 36 38
MIX HGT (KFT)...0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.6 0.6
TRANSP WIND DIR.S S S S S S S SW SW SW W W
TRANSP WIND SPD.8 9 12 13 15 17 20 21 23 26 30 32
FRIDAY
SKY/WEATHER.........MOSTLY SUNNY (40-50 PERCENT). SLIGHT CHANCE OF
RAIN LATE IN THE AFTERNOON.
MAX TEMPERATURE.....AROUND 57.
MIN HUMIDITY........29 PERCENT.
WIND (20 FT)........WEST WINDS 10 TO 20 MPH. GUSTS UP TO 35 MPH.
CWR.................0 PERCENT.
MIXING HEIGHT.......3200 TO 3700 FT AGL.
TRANSPORT WINDS.....WEST 35 TO 45 MPH INCREASING TO 45 TO 55 MPH IN
THE LATE MORNING AND AFTERNOON, THEN DECREASING
TO AROUND 40 MPH LATE IN THE AFTERNOON.
SMOKE DISPERSAL.....VERY GOOD DECREASING TO FAIR LATE IN THE
AFTERNOON.
TIME (MST) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........49 48 47 43 39 35 38 41 44 49 54 59
WEATHER COV..... SCH
WEATHER TYPE.... RN
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............44 45 47 50 52 55 56 56 56 55 54 52
RH..............46 45 42 39 35 32 31 29 30 30 32 34
20 FT WIND DIR..W W W W W W W W W W W W
20 FT WIND SPD..17 18 18 18 18 18 17 16 15 14 12 10
20 FT WIND GUST.40 41 43 43 41 40 39 38 36 33 30 28
MIX HGT (KFT)...0.7 0.7 0.8 1.3 1.7 2.1 2.7 3.2 3.7 2.9 2.1 1.3
TRANSP WIND DIR.W W W W W W W W W W W W
TRANSP WIND SPD.35 36 38 44 48 52 52 49 46 45 43 40
FORECASTER...EH
REQUESTED BY...LOGAN BROWN
TYPE OF REQUEST...WILDFIRE
.TAG 2527911.0/UNR
.DELDT 12/17/25
.FORMATTERVERSION 2.0.0
.EMAIL LOGAN_BROWN@FIRENET.GOV
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