903
FNUS75 KCYS 250400
FWSCYS
SPOT FORECAST FOR SOUTH FORK...USFS
NATIONAL WEATHER SERVICE CHEYENNE WY
1000 PM MDT WED JUN 24 2026
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE AT (307) 772-2227
DISCUSSION
THE UPPER LEVEL TROUGH WILL BE PUSHING EAST TONIGHT LIMITING THE SEVERE POTENTIAL
OVERNIGHT. THERE WILL BE A BRIEF BREAK IN COVERAGE BUT MODEL GUIDANCE HAVE THE
SHOWERS CONTINUING AROUND 09Z (3AM) FOR THE SOUTH FORK FIRE AREA AND CONTINUING THROUGH
THURSDAY MORNING. RH RECOVERY WILL BE ABOUT 80 TO 100 PERCENT WITH THE MINIMUM VALUE
AROUND 70 PERCENT THURSDAY AFTERNOON. SINCE THE OVERNIGHT COVERAGE WILL BE A LITTLE MORE
WIDESPREAD WITH HIGHER RH VALUES THE CHANCE FOR WETTING RAIN WITH THIS SHOWERS IS FAIRLY
HIGH AROUND 70 PERCENT. THIS STORMY PATTERN LOOKS TO LAST UNTIL THIS WEEKEND WHEN WE START
TO DRY OUT AS WESTERLY FLOW SETS IN AND DROPS RH VALUES INTO THE TEENS AND 20'S BY SATURDAY
AFTERNOON.
REST OF TONIGHT
SKY/WEATHER.........CLOUDY (95-100 PERCENT). RAIN SHOWERS AND
SLIGHT CHANCE OF THUNDERSTORMS.
CWR.................67 PERCENT.
MIN TEMPERATURE.....AROUND 49.
MAX HUMIDITY........100 PERCENT.
WIND (20 FT)........EAST WINDS 5 TO 7 MPH. GUSTY AND ERRATIC WINDS
EXPECTED NEAR THUNDERSTORMS.
MIXING HEIGHT.......600 FT AGL.
TRANSPORT WINDS.....EAST AROUND 9 MPH.
SMOKE DISPERSAL.....POOR (5100 KNOT-FT).
HAINES INDEX........MISSING.
TIME (MDT) 5AM
SKY (%).........98
WEATHER COV.....DEF
WEATHER TYPE....RW
TSTM COV........SCH
CWR.............70
TEMP............51
RH..............99
20 FT WIND DIR..E
20 FT WIND SPD..7
20 FT WIND GUST.14
MIX HGT (KFT)...0.6
TRANSP WIND DIR.E
TRANSP WIND SPD.9
HAINES INDEX....M
SDSPL KT-FT/10007
THURSDAY
SKY/WEATHER.........CLOUDY (85-95 PERCENT). SLIGHT CHANCE OF
THUNDERSTORMS IN THE MORNING. RAIN SHOWERS
THROUGH THE DAY. CHANCE OF THUNDERSTORMS IN THE
AFTERNOON. PATCHY FOG LATE IN THE MORNING.
CWR.................94 PERCENT DECREASING TO 29 PERCENT IN THE
AFTERNOON.
MAX TEMPERATURE.....AROUND 64.
MIN HUMIDITY........75 PERCENT.
WIND (20 FT)........EAST WINDS 5 TO 12 MPH WITH GUSTS TO AROUND 28
MPH SHIFTING TO THE SOUTHEAST 10 TO 12 MPH WITH
GUSTS TO AROUND 29 MPH LATE IN THE AFTERNOON.
GUSTY AND ERRATIC WINDS EXPECTED NEAR
THUNDERSTORMS IN THE MORNING. GUSTY AND ERRATIC
WINDS EXPECTED NEAR THUNDERSTORMS LATE IN THE
AFTERNOON.
MIXING HEIGHT.......2600 FT AGL.
TRANSPORT WINDS.....SOUTHEAST 9 TO 16 MPH.
SMOKE DISPERSAL.....POOR (5700 KNOT-FT) EARLY IN THE MORNING
INCREASING TO FAIR (41800 KNOT-FT) IN THE
AFTERNOON.
HAINES INDEX........MISSING.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........100 98 91 92 92 92 82 82 82 86 96 94
WEATHER COV.....LKY DEF DEF DEF DEF LKY DEF LKY LKY SCH CHC CHC
WEATHER TYPE....RW RW RW RW RW RW RW RW RW RW RW RW
TSTM COV........SCH SCH SCH SCH SCH SCH SCH CHC CHC
CWR.............90 90 90 90 90 90 30 30 30 30 30 30
TEMP............51 52 53 54 55 56 57 60 61 62 63 62
RH..............100 100 100 99 98 98 95 89 82 77 76 79
20 FT WIND DIR..E E E E E E SE SE SE SE SE SE
20 FT WIND SPD..7 7 7 7 8 9 9 10 12 12 12 12
20 FT WIND GUST.15 15 16 17 21 22 24 25 28 29 29 29
MIX HGT (KFT)...0.7 0.8 0.9 1.1 1.3 1.4 1.7 2.1 2.2 2.2 2.4 2.6
TRANSP WIND DIR.E E E E E E SE SE SE SE SE SE
TRANSP WIND SPD.9 10 12 10 10 12 12 13 14 15 15 16
HAINES INDEX....M M M M M M M M M M M M
SDSPL KT-FT/10008 11 13 13 13 16 21 25 29 34 37 42
THURSDAY NIGHT
SKY/WEATHER.........MOSTLY CLOUDY (70-80 PERCENT). RAIN SHOWERS
LIKELY AND CHANCE OF THUNDERSTORMS IN THE
EVENING.
CWR.................39 PERCENT DECREASING TO 3 PERCENT OVERNIGHT.
MIN TEMPERATURE.....AROUND 51.
MAX HUMIDITY........100 PERCENT.
WIND (20 FT)........SOUTH WINDS 10 TO 15 MPH WITH GUSTS TO AROUND
30 MPH. GUSTY AND ERRATIC WINDS EXPECTED NEAR
THUNDERSTORMS EARLY IN THE EVENING.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....SOUTH 15 TO 20 MPH.
SMOKE DISPERSAL.....POOR (7300 KNOT-FT).
HAINES INDEX........MISSING.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........82 87 92 99 90 81 68 58 51 67 66 64
WEATHER COV.....CHC LKY CHC SCH SCH
WEATHER TYPE....RW RW RW RW RW
TSTM COV........CHC CHC CHC
CWR.............40 40 40 40 40 40 0 0 0 0 0 0
TEMP............62 62 59 58 57 57 56 56 55 54 54 53
RH..............82 75 86 87 88 88 89 90 94 96 99 100
20 FT WIND DIR..S S S S S S S S S S SW S
20 FT WIND SPD..12 13 13 13 14 14 15 15 15 14 13 13
20 FT WIND GUST.28 28 29 28 29 29 30 30 30 29 28 26
MIX HGT (KFT)...2.4 1.5 1.1 0.9 0.8 0.7 0.8 0.6 0.6 0.6 0.6 0.5
TRANSP WIND DIR.S SE S S S S S SW SW SW SW SW
TRANSP WIND SPD.16 15 16 17 17 18 20 20 20 20 18 17
HAINES INDEX....M M M M M M M M M M M M
SDSPL KT-FT/100037 23 21 18 16 14 16 14 13 14 13 13
FRIDAY
SKY/WEATHER.........MOSTLY SUNNY (30-40 PERCENT).
CWR.................4 PERCENT.
MAX TEMPERATURE.....AROUND 86.
MIN HUMIDITY........37 PERCENT.
WIND (20 FT)........SOUTH WINDS 9 TO 16 MPH WITH GUSTS TO AROUND 35
MPH.
MIXING HEIGHT.......6300 FT AGL.
TRANSPORT WINDS.....SOUTH 13 TO 22 MPH INCREASING TO AROUND 24 MPH
LATE IN THE AFTERNOON.
SMOKE DISPERSAL.....POOR (6700 KNOT-FT) EARLY IN THE MORNING
INCREASING TO VERY GOOD (109500 KNOT-FT) IN THE
AFTERNOON.
HAINES INDEX........MISSING.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........67 57 33 33 16 9 6 11 18 13 39 37
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
TEMP............53 56 60 64 70 73 78 81 83 85 83 82
RH..............100 98 90 79 67 59 49 44 40 36 40 43
20 FT WIND DIR..SW S S S S S S S S S S S
20 FT WIND SPD..12 12 12 10 12 12 12 12 13 14 15 16
20 FT WIND GUST.26 25 24 23 24 25 26 28 30 32 33 35
MIX HGT (KFT)...0.5 0.9 1.2 1.4 1.9 2.4 3.4 5.0 6.3 6.1 4.0 2.0
TRANSP WIND DIR.SW SW SW SW S S S S S S S S
TRANSP WIND SPD.15 15 14 14 14 13 13 16 16 17 22 24
HAINES INDEX....M M M M M M M M M M M M
SDSPL KT-FT/100012 15 17 19 24 31 43 72 96 95 110 56
FORECASTER...MCLAUGHLIN
REQUESTED BY...DUELL PUTTERGILL
TYPE OF REQUEST...WILDFIRE
.TAG 2616177.0/CYS
.DELDT 06/24/26
.FORMATTERVERSION 2.0.0
.EMAIL DUELL.PUTTERGILL@USDA.GOV
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