898
FNUS75 KRIW 201450
FWSRIW
SPOT FORECAST FOR SVF UNIT 1...USFS-BTF
NATIONAL WEATHER SERVICE RIVERTON WY
850 AM MDT FRI MAR 20 2026
FORECAST IS BASED ON IGNITION TIME OF 0900 MDT ON MARCH 20.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE
DISCUSSION
ANOTHER WARM, DRY, AND SUNNY DAY IS EXPECTED. TEMPERATURES WILL BE
SIMILAR TO YESTERDAY, WITH MINIMUM HUMIDITY A LITTLE HIGHER
PEAKING IN THE LOW 20 PERCENT RANGE. WIND WILL BE PRIMARILY
TERRAIN DRIVEN, GENERALLY OUT OF THE WEST AT THE UNIT. LIKE
YESTERDAY, GUSTS OF 15 MPH CAN BE EXPECTED AFTER 1200 WITH AN
OCCASIONAL GUST NEARING 20 MPH AT HIGHER TERRAIN. EXPECT WIND TO
DECREASE AFTER 1800, TRANSITIONING TO DOWNSLOPE/DOWNVALLEY BY
2100. HUMIDITY RECOVERY IS EXPECTED TO BE POOR TONIGHT, ONLY
INCREASING TO AROUND 45 PERCENT.
SATURDAY WILL SEE INCREASING HIGH CLOUDS AHEAD OF AN INCOMING COLD
FRONT. WIND WILL BE STRONGER OUT OF THE WEST. THERE WILL BE A 20
PERCENT CHANCE OF A RAIN SHOWER SATURDAY NIGHT THOUGH LITTLE TO
NO PRECIPITATION ACCUMULATION IS EXPECTED.
..THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS
REST OF TODAY
SKY/WEATHER.........SUNNY (5-15 PERCENT).
CWR.................0 PERCENT.
CHANCE OF PCPN......0 PERCENT.
CHANCE OF THUNDER...0 PERCENT.
MAX TEMPERATURE.....AROUND 66.
MIN HUMIDITY........24 PERCENT.
WIND (20 FT)........SOUTHWEST WIND AROUND 5 MPH UNTIL 1200, THEN
BECOMING WEST AROUND 7 MPH WITH GUSTS TO 15 MPH.
RIDGETOP WIND.......SOUTHWEST 10 TO 15 MPH UNTIL 1300, THEN WEST.
MIXING HEIGHT.......INCREASING TO 5000 FT AGL BY 1400.
TRANSPORT WINDS.....SOUTHWEST 9 TO 13 MPH UNTIL 1500, THEN 13 TO 14
MPH.
SMOKE DISPERSAL.....POOR INCREASING TO GOOD BY 1500.
TIME (MDT) 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........10 10 15 10 5 0 5 5 5
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0
CHC OF THDR (%).0 0 0 0 0 0 0 0 0
TEMP............45 50 56 56 60 62 63 63 64
RH..............62 54 45 35 31 26 24 24 26
20 FT WIND DIR..SW SW SSW SSW W W W W W
20 FT WIND SPD..4 4 6 6 6 7 7 7 7
20 FT WIND GUST.6 6 8 11 12 15 15 16 14
RIDGE WIND DIR..SW SW SW SW W W W W W
RIDGE WIND SPD..10 10 10 11 15 16 16 17 16
MIX HGT (KFT)...1.0 1.5 2.0 3.0 4.0 5.0 5.0 4.5 3.5
TRANSP WIND DIR.S S SW SW SW W W SW SW
TRANSP WIND SPD.9 9 10 10 12 13 14 13 13
SDSPL KT-FT/10009 10 18 28 38 53 60 49 39
TONIGHT
SKY/WEATHER.........MOSTLY CLEAR (5-15 PERCENT).
CWR.................0 PERCENT.
CHANCE OF PCPN......0 PERCENT.
CHANCE OF THUNDER...0 PERCENT.
MIN TEMPERATURE.....AROUND 46.
MAX HUMIDITY........43 PERCENT.
WIND (20 FT)........SOUTHWEST AROUND 7 MPH BECOMING DOWNSLOPE/DOWNVALLEY
AROUND 5 MPH AFTER 2100.
RIDGETOP WIND.......SOUTH 10 TO 15 MPH.
MIXING HEIGHT.......1000 FT AGL.
TRANSPORT WINDS.....SOUTH 12 TO 14 MPH.
SMOKE DISPERSAL.....POOR.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........5 10 5 5 5 5 5 5 5 5 5 5
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0 0 0 0
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 0 0 0
TEMP............61 60 57 51 50 49 48 48 47 47 46 46
RH..............33 33 37 42 42 44 42 42 40 38 38 40
20 FT WIND DIR..SW S S SE E E E E E SE E SE
20 FT WIND SPD..7 6 6 5 5 5 5 5 5 5 5 5
20 FT WIND GUST.11 10 8 7 7 7 7 7 7 7 7 7
RIDGE WIND DIR..SW S S SE SE SE SE SE SE SE SE SE
RIDGE WIND SPD..15 15 10 10 10 10 10 10 10 10 10 10
MIX HGT (KFT)...2.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
TRANSP WIND DIR.SW S S S S S S S S S S S
TRANSP WIND SPD.14 13 12 12 12 12 12 13 13 12 12 12
SDSPL KT-FT/100031 14 11 11 11 11 11 12 12 11 11 11
SATURDAY
SKY/WEATHER.........MOSTLY SUNNY (25-35 PERCENT).
CWR.................0 PERCENT.
CHANCE OF PCPN......0 PERCENT.
CHANCE OF THUNDER...0 PERCENT.
MAX TEMPERATURE.....AROUND 64.
MIN HUMIDITY........36 PERCENT.
WIND (20 FT)........SOUTH AROUND 5 MPH BECOMING WEST
RIDGETOP WIND.......SOUTH 10 TO 15 MPH UNTIL 1200, THEN WEST 15 TO
20 MPH.
MIXING HEIGHT.......1500 FT AGL UNTIL 1100, THEN 4000 FT AGL UNTIL
1300, THEN 6500 FT AGL UNTIL 1500, THEN 7500 FT
AGL UNTIL 1700, THEN 5500 FT AGL.
TRANSPORT WINDS.....SOUTH 10 TO 18 MPH UNTIL 1300, THEN WEST 21 TO
25 MPH.
SMOKE DISPERSAL.....POOR UNTIL 1200, THEN GOOD UNTIL 1400, THEN
VERY GOOD EARLY IN THE MORNING INCREASING TO
EXCELLENT IN THE AFTERNOON UNTIL 1700, THEN
VERY GOOD.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........5 10 15 15 20 20 20 25 30 40 45 50
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0 0 0 0
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 0 0 0
TEMP............46 47 47 48 52 55 59 60 61 62 60 59
RH..............40 40 38 39 38 37 36 35 35 35 36 38
20 FT WIND DIR..SE S S S S SW SW W W W NW NW
20 FT WIND SPD..5 5 5 5 6 8 10 12 14 15 15 14
20 FT WIND GUST.7 7 7 7 8 11 13 16 18 20 20 19
RIDGE WIND DIR..SE S S S S SW SW W W W NW NW
RIDGE WIND SPD..10 10 10 10 10 15 15 15 15 15 20 20
MIX HGT (KFT)...1.0 1.0 1.0 1.0 1.5 3.0 4.0 5.0 6.5 7.5 6.5 5.5
TRANSP WIND DIR.S S S S S SW SW SW W W NW NW
TRANSP WIND SPD.12 12 12 10 13 16 18 21 23 25 24 22
SDSPL KT-FT/100011 11 11 9 19 39 62 92 127 167 136 103
FORECAST DAYS 3 THROUGH 5
SUNDAY
PARTLY CLOUDY. SLIGHT CHANCE OF SHOWERS. LOWS IN THE MID 30S.
HIGHS IN THE MID 50S. WEST WINDS 4 TO 8 MPH WITH GUSTS TO AROUND
12 MPH.
MONDAY
PARTLY CLOUDY. LOWS IN THE LOWER 30S. HIGHS IN THE MID 50S. WEST
WINDS 5 O 10 MPH WITH GUSTS TO AROUND 15 MPH.
TUESDAY
MOSTLY CLOUDY. LOWS IN THE MID 30S. HIGHS AROUND 60. WEST WINDS 4
TO 8 MPH WITH GUSTS TO AROUND 12 MPH.
FORECASTER...MYERS
REQUESTED BY...MICHAEL MCEWEN
TYPE OF REQUEST...PRESCRIBED
.TAG 2605908.2/RIW
.DELDT 03/20/26
.FORMATTERVERSION 2.0.0
.EMAIL MICHAEL.MCEWEN@USDA.GOV
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