293
FNUS73 KUNR 022339
FWSUNR
SPOT FORECAST FOR BROKEN JAW...CASPER DISPATCH
NATIONAL WEATHER SERVICE RAPID CITY SD
539 PM MDT WED SEP 2 2026
FORECAST IS BASED ON FORECAST START TIME OF 1800 MDT ON SEPTEMBER 02.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE.
..RED FLAG WARNING IN EFFECT FROM NOON TO 8 PM MDT THURSDAY
DISCUSSION
CRITICAL FIRE WEATHER CONDITIONS TONIGHT THROUGH FRIDAY.
TONIGHT: POOR OVERNIGHT RELATIVE HUMIDITY RECOVERY (AROUND 45 PERCENT)
COUPLED WITH BREEZY SOUTHERLY WINDS THROUGH THE OVERNIGHT HOURS. CLOUDS
WILL INCREASE, BUT NO PRECIPITATION OR LIGHTNING IS EXPECTED TONIGHT.
CRITICAL FIRE WEATHER CONDITIONS THURSDAY (RFW IN EFFECT FOR THE FIRE
AREA) WITH RELATIVE HUMIDITY FALLING TO AROUND 9-10 PERCENT WITH SOUTHERLY
WINDS; SUSTAINED WINDS 10 TO 15 MPH WITH GUSTS 25 TO 30 MPH THROUGH
THE AFTERNOON.
VERY POOR OVERNIGHT RH RECOVERY EXPECTED THURSDAY NIGHT AND FRIDAY
MORNING (AROUND 30 PERCENT) WITH CONTINUED BREEZY SOUTHERLY WINDS
(GUSTS 20 TO 30+ MPH OVERNIGHT). VERY HOT (92-94F) AND DRY FRIDAY
(POOR OVERNIGHT RH RECOVERY FALLING TO AROUND 10 PERCENT BY PEAK HEATING)
ALONG WITH GUSTY SOUTHWEST WINDS WILL RESULT IN CRITICAL FIRE WEATHER
CONDITIONS AGAIN FRIDAY.
TONIGHT
SKY/WEATHER.........PARTLY CLOUDY (25-35 PERCENT) THEN BECOMING
MOSTLY CLOUDY (60-70 PERCENT).
MIN TEMPERATURE.....AROUND 60.
MAX HUMIDITY........45-50 PERCENT.
WIND (20 FT)........SOUTHWEST WINDS 10 TO 20 MPH WITH GUSTS TO
AROUND 32 MPH SHIFTING TO THE SOUTH AROUND 10
MPH WITH GUSTS TO AROUND 14 MPH AFTER 3 AM.
CWR.................0 PERCENT.
MIXING HEIGHT.......2600 TO 3100 FT AGL DECREASING TO 500 TO 1000
FT AGL EARLY IN THE EVENING.
TRANSPORT WINDS.....SOUTHWEST 25 TO 30 MPH BECOMING SOUTH 10 TO 20
MPH OVERNIGHT.
SMOKE DISPERSAL.....EXCELLENT DECREASING TO POOR.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........14 21 33 40 42 44 51 59 69 76 76 76
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............85 81 77 74 72 71 69 68 67 65 61 60
RH..............20 24 28 32 31 30 32 34 36 38 44 45
20 FT WIND DIR..SW SW SW SW SW SW SW SW S S S S
20 FT WIND SPD..17 16 14 13 13 13 13 12 9 7 7 6
20 FT WIND GUST.32 28 24 22 23 23 23 21 17 14 13 12
MIX HGT (KFT)...11 2.6 0.8 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.SW SW SW SW SW SW S S S S S S
TRANSP WIND SPD.30 26 23 21 21 22 22 18 15 13 10 10
THURSDAY
SKY/WEATHER.........MOSTLY SUNNY (30-40 PERCENT).
MAX TEMPERATURE.....AROUND 86.
MIN HUMIDITY........9-13 PERCENT.
WIND (20 FT)........SOUTH WINDS 10 TO 15 MPH WITH GUSTS TO AROUND
26 MPH SHIFTING TO THE SOUTHWEST AROUND 20 MPH
WITH GUSTS TO AROUND 30 MPH IN THE AFTERNOON.
CWR.................0 PERCENT.
MIXING HEIGHT.......9700 TO 10200 FT AGL INCREASING TO 11400 TO
11900 FT AGL LATE IN THE AFTERNOON.
TRANSPORT WINDS.....SOUTH 10 TO 20 MPH INCREASING TO SOUTHWEST 25
TO 30 MPH LATE IN THE MORNING.
SMOKE DISPERSAL.....GOOD INCREASING TO EXCELLENT.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........67 64 26 4 3 12 14 15 13 7 11 9
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............60 62 65 69 74 78 81 83 84 86 86 86
RH..............46 43 40 36 28 23 18 15 13 11 11 11
20 FT WIND DIR..S S S S S S S SW SW SW SW SW
20 FT WIND SPD..6 7 8 8 10 12 14 16 16 17 17 16
20 FT WIND GUST.12 12 14 15 17 22 26 29 30 30 30 30
MIX HGT (KFT)...0.5 0.4 0.5 1.3 2.7 5.0 8.4 10 11 12 12 11
TRANSP WIND DIR.S S S S S SW SW SW SW SW SW SW
TRANSP WIND SPD.10 10 12 14 17 21 24 26 28 29 29 29
THURSDAY NIGHT
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT).
MIN TEMPERATURE.....AROUND 65.
MAX HUMIDITY........30-35 PERCENT.
WIND (20 FT)........SOUTH WINDS 10 TO 20 MPH INCREASING TO AROUND
20 MPH EARLY IN THE MORNING. GUSTS UP TO 29 MPH
DECREASING TO 26 MPH IN THE LATE EVENING AND
OVERNIGHT, THEN INCREASING TO 32 MPH AFTER 3
AM.
CWR.................0 PERCENT.
MIXING HEIGHT.......500 TO 1000 FT AGL.
TRANSPORT WINDS.....SOUTH 20 TO 30 MPH DECREASING TO 20 TO 25 MPH
IN THE LATE EVENING AND OVERNIGHT, THEN
INCREASING TO AROUND 30 MPH AFTER 3 AM.
SMOKE DISPERSAL.....VERY GOOD DECREASING TO POOR EARLY IN THE
EVENING.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........20 24 30 26 16 16 19 19 20 18 9 13
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............85 82 78 72 70 68 68 67 67 67 67 67
RH..............11 12 14 17 18 20 20 23 24 25 27 27
20 FT WIND DIR..SW SW S S S S S S S S S S
20 FT WIND SPD..16 12 10 9 9 12 12 13 15 17 18 20
20 FT WIND GUST.29 23 20 17 18 20 21 23 26 29 31 32
MIX HGT (KFT)...10 7.1 3.8 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.SW S S S S S S S S S S S
TRANSP WIND SPD.26 23 18 16 16 17 20 22 25 28 29 30
FORECASTER...SE
REQUESTED BY...MOLLY WARTENBEE
TYPE OF REQUEST...WILDFIRE
.TAG 2621124.0/UNR
.DELDT 09/02/26
.FORMATTERVERSION 2.0.0
.EMAIL WYCPC@BLM.GOV
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page