FNUS75 KRIW 182104 FWSRIW Spot Forecast for Spread Creek...USFS National Weather Service Riverton WY 304 PM MDT Mon May 18 2026 Forecast is based on forecast start time of 0700 MDT on May 19. If conditions become unrepresentative, contact the National Weather Service .DISCUSSION... Any lingering snow showers have dissipated and pushed east for the remainder of the day remaining dry overnight as well as for Tuesday. Mostly sunny skies and light winds tomorrow, with a bit increasing westerly winds between 0900-1600 up to around 12 mph. Afternoon high temperatures around 3 to 5 degrees warmer tomorrow afternoon with humidity values dropping to near 30 percent. Next weather system will bring increasing clouds and precipitation for Wednesday afternoon, as well as stronger winds to go along with it lasting overnight into Thursday. ...Thunderstorms imply strong gusty and erratic winds... .TUESDAY... Sky/weather.........Sunny (15-25 percent). CWR.................0 percent. Chance of pcpn......0 percent. Chance of thunder...0 percent. Max temperature.....Around 49. Min humidity........29 percent. Wind (20 ft)........Light winds until 0900, then west-northwest 8 to 12 mph until 1600, then light there after. Ridgetop wind.......Southeast around 10 mph until 0800, then light until 1000, then northwest 10 to 15 mph. Mixing height.......1500 ft AGL until 0900. 8500 ft AGL after 1200. Transport winds.....Southeast around 8 mph until 0800, then light until 0900, then west 7 to 15 mph. Smoke dispersal.....Poor until 0900, then good through 1600 before becoming poor once again. TIME (MDT) 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........15 15 10 10 15 15 15 20 20 25 30 Weather cov..... Weather type.... Tstm cov........ CWR.............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 Chc of thdr (%).0 0 0 0 0 0 0 0 0 0 0 Temp............24 27 31 37 40 42 44 46 47 47 48 RH..............75 68 58 49 41 35 34 30 29 28 28 20 FT wind dir..SE NW NW NW NW NW W W W NW W 20 FT wind spd..3 1 2 4 5 6 7 8 8 6 7 20 FT wind gust.5 2 4 6 7 10 10 11 12 10 11 Ridge wind dir..SE NW NW NW NW NW W W W NW W Ridge wind spd..10 5 5 10 10 10 15 15 15 15 15 Mix hgt (kft)...0.5 1.5 2.5 4.5 6.0 7.0 8.0 8.5 8.5 8.0 7.5 Transp wind dir.SE S W NW NW W W W W W W Transp wind spd.8 6 7 9 10 12 14 15 15 13 14 SDspl kt-ft/10004 8 15 35 53 70 99 112 113 87 92 .TUESDAY NIGHT... Sky/weather.........Partly cloudy (30-40 percent) then becoming mostly clear (5-15 percent). CWR.................0 percent. Chance of pcpn......0 percent. Chance of thunder...1 percent. Min temperature.....Around 26. Max humidity........71 percent. Wind (20 ft)........West winds around 7 mph with gusts to around 12 mph until 1900, then light. Ridgetop wind.......West 10 to 15 mph until 2100, then southeast. Mixing height.......5500 ft AGL until 2000, then 500 ft AGL. Transport winds.....West 10 to 14 mph until 2200, then south 9 to 10 mph. Smoke dispersal.....Good until 1900. Poor after 2000. TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........45 45 40 20 25 20 20 5 5 5 10 10 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............47 46 43 38 36 34 32 31 30 29 28 28 RH..............29 31 39 43 47 52 57 62 66 68 69 69 20 FT wind dir..W W SW S S S SE SE SE SE SE SE 20 FT wind spd..7 6 6 5 5 5 4 4 4 4 4 4 20 FT wind gust.12 11 8 8 8 8 10 8 8 8 7 7 Ridge wind dir..W W SW S S S SE SE SE SE SE SE Ridge wind spd..15 10 15 10 10 10 10 10 10 10 10 10 Mix hgt (kft)...7.0 5.5 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Transp wind dir.W W W SW SW SW S S S S S S Transp wind spd.14 12 13 10 10 10 9 9 9 9 9 9 SDspl kt-ft/100083 54 9 5 5 4 4 4 4 4 4 4 .WEDNESDAY... Sky/weather.........Mostly sunny (30-40 percent). CWR.................0 percent. Chance of pcpn......10 percent. Chance of thunder...7 percent. Max temperature.....Around 52. Min humidity........33 percent. Wind (20 ft)........Light winds until 0900, then west 5 to 10 mph with gusts to around 15 mph. Ridgetop wind.......Southeast around 10 mph until 0900, then west. Mixing height.......1000 ft AGL until 0800. 7500 ft AGL after 1100. Transport winds.....South 8 to 10 mph until 1000, then west 12 to 17 mph. Smoke dispersal.....Poor until 0900, then good there after. TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........5 5 10 15 20 25 30 40 45 50 55 60 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 10 10 10 10 10 10 Chc of thdr (%).0 0 0 0 0 0 10 10 10 10 10 10 Temp............27 31 35 38 42 45 47 49 50 50 51 51 RH..............71 65 57 49 43 39 37 36 35 35 34 33 20 FT wind dir..SE SE S SW SW SW W W W W W W 20 FT wind spd..4 3 3 3 4 5 6 6 6 6 7 7 20 FT wind gust.6 6 6 6 8 10 12 13 13 14 16 17 Ridge wind dir..SE SE S SW SW SW W W W W W W Ridge wind spd..10 10 10 10 10 10 10 10 15 15 15 15 Mix hgt (kft)...0.5 1.0 2.5 4.5 5.5 6.5 7.5 7.5 7.5 7.5 7.5 7.5 Transp wind dir.S SE S SW W W W W W W W W Transp wind spd.9 8 9 10 12 13 14 15 16 17 16 16 SDspl kt-ft/10004 7 21 39 53 69 87 95 103 111 102 102 .FORECAST DAYS 3 THROUGH 5... .THURSDAY... Snow showers with possible showers and thunderstorms likely. Lows in the mid 30s. Highs in the upper 40s. Light winds. .FRIDAY... Partly cloudy. Slight chance of showers, thunderstorms and snow showers. Lows around 30. Highs in the mid 50s. Light winds. .SATURDAY... Partly cloudy. Lows in the lower 30s. Highs in the lower 60s. Light winds. $$ Forecaster...Lowe Requested by...Greg mann Type of request...WILDFIRE .TAG 2613964.0/RIW .DELDT 05/18/26 .FormatterVersion 2.0.0 .EMAIL 2026.spreadcreek@firenet.gov