Spot Forecast
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
971 FNUS75 KRIW 181029 FWSRIW Spot Forecast for Star Valley Front 2B-8...USFS BTNF National Weather Service Riverton WY 429 AM MDT Thu Apr 18 2024 Forecast is based on ignition time of 0900 MDT on April 18. If conditions become unrepresentative, contact the National Weather Service .DISCUSSION... Slightly below normal temperatures today, with precipitation chances remaining under 10% today and tomorrow. Winds remain light through the day, generally less than 10mph. Variable direction in the morning due to the light speeds and terrain influence. Upslope winds become more dominating around 1000L in the morning, shifting northerly around 1200L. Winds then shift easterly around 2100L, continuing into Friday morning. ...Thunderstorms imply strong gusty and erratic winds... ...Haines index is high level haines both day and night... .REST OF TODAY... Sky/weather.........Sunny (15-25 percent). CWR.................0 percent. Chance of pcpn......10 percent. LAL.................1. Max temperature.....Around 42. Min humidity........35-39 percent. Wind (20 ft)........Light winds becoming north 5 to 9 mph in the afternoon. Ridgetop wind.......Northeast 5 to 10 mph shifting to the north around 15 mph late in the afternoon. Mixing height.......1000 ft AGL increasing to 4700 ft AGL in the afternoon. Transport winds.....East around 6 mph shifting to the west 8 to 14 mph in the afternoon. Smoke dispersal.....Poor (4800 knot-ft) early in the morning increasing to fair (55900 knot-ft) in the afternoon. Haines Index........2 or very low potential for large plume dominated fire growth. TIME (MDT) 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........17 14 13 16 18 13 21 20 23 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 10 0 LAL.............1 1 1 1 1 1 1 1 1 Temp............25 28 31 35 37 38 40 41 42 RH..............77 71 63 57 53 46 37 43 43 20 FT wind dir..SE W NE N NE NE N N N 20 FT wind spd..2 2 3 3 4 4 6 7 8 20 FT wind gust. 4 4 6 6 8 10 12 Ridge wind dir..NE NE NE NE NE NE N N N Ridge wind spd..5 5 5 10 10 10 15 15 15 Mix hgt (kft)...1.0 1.0 1.0 4.1 4.1 4.1 4.7 4.7 4.7 Transp wind dir.E E E W W W W W W Transp wind spd.6 6 6 8 8 8 14 14 14 Haines index....2 2 2 2 2 2 2 2 2 SDspl kt-ft/10005 5 5 29 29 29 56 56 56 .TONIGHT... Sky/weather.........Partly cloudy (25-35 percent). CWR.................0 percent. Chance of pcpn......0 percent. LAL.................1. Min temperature.....Around 23. Max humidity........76-80 percent. Wind (20 ft)........Northeast winds 9 to 11 mph becoming light. Ridgetop wind.......Northeast 10 to 15 mph shifting to the east around 5 mph overnight. Mixing height.......3700 ft AGL decreasing to 500 ft AGL in the late evening and overnight. Transport winds.....West around 17 mph shifting to the north late in the evening, then shifting to the southeast overnight. Smoke dispersal.....Fair (56100 knot-ft) early in the evening decreasing to poor (3000 knot-ft) late in the night. Haines Index........2 or very low potential for large plume dominated fire growth. TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........30 39 30 27 26 24 24 26 32 29 29 23 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 LAL.............1 1 1 1 1 1 1 1 1 1 1 1 Temp............42 40 37 34 31 30 29 28 27 26 25 24 RH..............45 42 55 57 62 63 66 68 73 78 79 79 20 FT wind dir..NE NE NE E E NE E E E E E E 20 FT wind spd..9 11 10 8 6 3 3 2 2 2 2 2 20 FT wind gust.13 16 14 12 10 4 4 Ridge wind dir..NE NE NE E E E E E E E E E Ridge wind spd..15 15 15 10 10 10 5 5 5 5 5 5 Mix hgt (kft)...3.7 3.7 3.7 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Transp wind dir.W W W N N N SE SE SE SE SE SE Transp wind spd.17 17 17 12 12 12 7 7 7 7 7 7 Haines index....2 2 2 2 2 2 2 2 2 2 2 2 SDspl kt-ft/100056 56 56 5 5 5 3 3 3 3 3 3 .FRIDAY... Sky/weather.........Mostly sunny (30-40 percent). CWR.................0 percent. Chance of pcpn......0 percent. LAL.................1. Max temperature.....Around 45. Min humidity........35 percent. Wind (20 ft)........Light winds becoming northeast 5 to 8 mph late in the afternoon, then shifting to the north around 6 mph late in the afternoon. Ridgetop wind.......East around 5 mph shifting to the northeast in the late morning and early afternoon, then shifting to the north around 15 mph late in the afternoon. Mixing height.......500 ft AGL increasing to 5000 ft AGL. Transport winds.....Southeast around 7 mph shifting to the west 7 to 13 mph in the late morning and afternoon. Smoke dispersal.....Poor (3000 knot-ft) early in the morning increasing to fair (55500 knot-ft) in the afternoon. Haines Index........2 or very low potential for large plume dominated fire growth. TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........16 16 15 14 20 23 25 30 35 40 48 55 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 LAL.............1 1 1 1 1 1 1 1 1 1 1 1 Temp............24 25 27 29 33 36 40 41 42 44 45 45 RH..............78 73 69 65 64 50 49 37 35 35 35 36 20 FT wind dir..E E E E NE N NE NE NE NE NE N 20 FT wind spd..2 3 2 2 3 3 4 5 6 6 8 6 20 FT wind gust. 4 4 4 5 6 8 10 12 10 Ridge wind dir..E E E NE NE NE NE NE NE N N N Ridge wind spd..5 5 5 5 5 5 10 10 10 15 15 15 Mix hgt (kft)...0.5 0.5 0.5 1.9 1.9 1.9 4.3 4.3 4.3 5.0 5.0 5.0 Transp wind dir.SE SE SE SW SW SW W W W W W W Transp wind spd.7 7 7 7 7 7 10 10 10 13 13 13 Haines index....2 2 2 2 2 2 2 2 2 2 2 2 SDspl kt-ft/10003 3 3 11 11 11 39 39 39 56 56 56 .FORECAST DAYS 3 THROUGH 5... .SATURDAY... Partly cloudy. Lows in the upper 20s. Highs in the lower 50s. Light winds. .SUNDAY... Partly cloudy. Chance of showers. Lows in the lower 30s. Highs in the upper 50s. Southwest winds around 7 mph. .MONDAY... Partly cloudy. Lows in the upper 20s. Highs in the mid 50s. West winds around 9 mph. $$ Forecaster...Wittmann Requested by...Michael McEwen Type of request...PRESCRIBED .TAG 2411223.0/RIW .DELDT 04/18/24 .FormatterVersion 2.0.0 .EMAIL michael.mcewen@usda.gov