091
FNUS75 KCYS 302207
FWSCYS
SPOT FORECAST FOR SAWMILL FIRE...CASPER INTERAGENCY DISPATCH CENTER
NATIONAL WEATHER SERVICE CHEYENNE WY
407 PM MDT THU JUL 30 2026
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE AT (307) 772-2227
DISCUSSION
ISOLATED THUNDERSTORM CHANCES FOR THIS EVENING AND TOMORROW AS WELL.
DUE TO THE ISOLATED COVERAGE, LOW MODEL CONFIDENCE, AND BUILDING DRY
LAYER NEAR THE SURFACE TO REALLY DECREASE THE CHANCES FOR A WETTING
RAIN (LESS THAN 10% UNTIL ABOUT TUESDAY). A BUILDING UPPER LEVEL RIDGE
WILL START TO DRY THE REGION THIS WEEKEND RAISING THE TEMPERATURES INTO
THE 90'S AND 100'S. RH VALUES WILL ALSO START DROP BELOW 20 PERCENT
STARTING THE FRIDAY AFTERNOON. NOCTURNAL INVERSIONS WILL KEEP THE WINDS
BELOW 10 MPH AFTER 10 PM EACH NIGHT KEEPING SMOKE DISPERSAL AND TRANSPORT
WINDS IN POOR CONDITIONS. DIURNAL MIXING SHOULD HELP ALLEVIATE ANY SMOKE
DISPERSAL CONCERNS DURING THE DAY.
REST OF TODAY
SKY/WEATHER.........MOSTLY SUNNY (20-30 PERCENT). SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS.
CWR.................6 PERCENT.
MAX TEMPERATURE.....AROUND 85.
MIN HUMIDITY........27 PERCENT.
WIND (20 FT)........NORTHWEST WINDS AROUND 14 MPH. GUSTY AND
ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS.
MIXING HEIGHT.......9400 FT AGL.
TRANSPORT WINDS.....NORTHWEST 18 TO 20 MPH.
SMOKE DISPERSAL..... VERY GOOD (141300 KNOT-FT) EARLY IN THE
MORNING INCREASING TO EXCELLENT (159200
KNOT-FT) IN THE AFTERNOON.
TIME (MDT) 4PM 5PM
SKY (%).........25 27
WEATHER COV.....SCH SCH
WEATHER TYPE....RW RW
TSTM COV........SCH SCH
CWR.............10 10
TEMP............82 81
RH..............28 29
20 FT WIND DIR..NW N
20 FT WIND SPD..14 14
20 FT WIND GUST.26 25
MIX HGT (KFT)...9.4 8.8
TRANSP WIND DIR.NW NW
TRANSP WIND SPD.20 18
SDSPL KT-FT/1000159 141
TONIGHT
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT). SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS EARLY IN THE EVENING.
CWR.................5 PERCENT.
MIN TEMPERATURE.....AROUND 59.
MAX HUMIDITY........62 PERCENT.
WIND (20 FT)........NORTH WINDS 5 TO 13 MPH IN THE EVENING BECOMING
LIGHT, THEN BECOMING SOUTHWEST AROUND 5 MPH
EARLY IN THE MORNING. GUSTY AND ERRATIC WINDS
EXPECTED NEAR THUNDERSTORMS EARLY IN THE
EVENING.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....NORTH 8 TO 17 MPH SHIFTING TO THE WEST 7 TO 8
MPH OVERNIGHT.
SMOKE DISPERSAL..... VERY GOOD (114800 KNOT-FT) EARLY IN THE
EVENING DECREASING TO GOOD (78800 KNOT-FT) LATE
IN THE NIGHT DECREASING TO POOR (2800 KNOT-FT)
EARLY IN THE EVENING.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........25 32 24 20 8 8 6 8 12 8 10 13
WEATHER COV.....SCH SCH SCH
WEATHER TYPE....RW RW RW
TSTM COV........SCH SCH SCH
CWR.............10 10 10 10 10 10 0 0 0 0 0 0
TEMP............80 77 75 72 70 68 66 65 64 63 62 62
RH..............31 35 37 41 46 49 54 56 58 60 60 58
20 FT WIND DIR..N N N N N N N NW W W W SW
20 FT WIND SPD..13 12 9 7 6 5 3 3 3 3 3 5
20 FT WIND GUST.24 22 17 14 10 8 7 6 7 7 8 8
MIX HGT (KFT)...7.7 6.1 0.8 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.NW N NW N N N NW W W W SW SW
TRANSP WIND SPD.17 15 13 10 9 8 9 8 7 8 7 7
SDSPL KT-FT/1000115 79 8 5 4 4 4 4 3 3 3 3
FRIDAY
SKY/WEATHER.........SUNNY (20-30 PERCENT) THEN BECOMING PARTLY
SUNNY (60-70 PERCENT). SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS EARLY IN THE AFTERNOON.
CHANCE OF SHOWERS AND THUNDERSTORMS LATE IN THE
AFTERNOON.
CWR.................7 PERCENT.
MAX TEMPERATURE.....AROUND 83.
MIN HUMIDITY........21 PERCENT.
WIND (20 FT)........SOUTHWEST WINDS AROUND 5 MPH EARLY IN THE
MORNING BECOMING LIGHT, THEN BECOMING EAST 5 TO
9 MPH IN THE LATE MORNING AND AFTERNOON. GUSTY
AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS
IN THE AFTERNOON.
MIXING HEIGHT.......8700 FT AGL INCREASING TO 11900 FT AGL IN THE
AFTERNOON.
TRANSPORT WINDS.....SOUTH 6 TO 7 MPH SHIFTING TO THE SOUTHEAST
AROUND 7 MPH EARLY IN THE MORNING, THEN
SHIFTING TO THE NORTH 8 TO 10 MPH LATE IN THE
MORNING SHIFTING TO THE SOUTH AROUND 10 MPH
EARLY IN THE AFTERNOON SHIFTING TO THE NORTH
SHIFTING TO THE NORTHEAST LATE IN THE
AFTERNOON.
SMOKE DISPERSAL.....POOR (2500 KNOT-FT) EARLY IN THE MORNING
INCREASING TO VERY GOOD (101300 KNOT-FT) IN THE
AFTERNOON INCREASING TO GOOD (96300 KNOT-FT)
EARLY IN THE MORNING INCREASING TO VERY GOOD
(114200 KNOT-FT) IN THE AFTERNOON LATE IN THE
AFTERNOON.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........16 9 8 8 8 12 9 15 12 16 42 67
WEATHER COV..... SCH SCH SCH CHC CHC CHC
WEATHER TYPE.... RW RW RW RW RW RW
TSTM COV........ SCH SCH SCH CHC CHC CHC
CWR.............0 0 0 0 0 0 10 10 10 10 10 10
TEMP............60 63 67 69 73 77 79 81 82 82 83 82
RH..............62 56 49 45 37 31 27 24 22 22 21 22
20 FT WIND DIR..SW SW S SE SE E E E E E E E
20 FT WIND SPD..5 5 3 3 5 6 7 7 7 7 8 9
20 FT WIND GUST.9 8 7 7 8 10 12 13 14 14 16 17
MIX HGT (KFT)...0.5 0.5 1.0 1.8 3.5 5.9 8.7 11 11 12 11 8.8
TRANSP WIND DIR.SW S SE SE SE N N NW S N NE NE
TRANSP WIND SPD.7 6 7 7 7 8 10 10 10 10 10 15
SDSPL KT-FT/10003 3 6 11 21 41 78 98 101 107 96 114
FORECASTER...MCLAUGHLIN
REQUESTED BY...THEODORE DONOGHUE
TYPE OF REQUEST...WILDFIRE
.TAG 2618593.1/CYS
.DELDT 07/30/26
.FORMATTERVERSION 2.0.0
.EMAIL JBISIAR@BLM.GOV,WYCPC@FIRENET.GOV
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