FNUS75 KRIW 101105 FWSRIW Spot Forecast for Slough South RX...NPS National Weather Service Riverton WY 505 AM MDT Fri Apr 10 2026 Forecast is based on ignition time of 0700 MDT on April 10. If conditions become unrepresentative, contact the National Weather Service .DISCUSSION... A light north-northeast wind starts the day. By around 1200, winds shift to be from the southwest with speeds 5 to 8 mph. Though gusts 10 to 15 mph may start around 1200, better chances for those speeds start around 1400, when gusts up to 20 mph are likely. For precipitation chances today, a light shower is possible as early as 1100 (10% chance) with the peak chances of today occurring between 1400 and 1900 (15% hourly chances). If a shower were to occur, any rain would be very light, if any even reaches the ground. The chances of a wetting rain (0.1") is near zero. Notably, there is a chance a shower becomes a thunderstorm (15%) this afternoon. Tonight, winds prevail from the south to southwest at speeds 5 to 8 mph. An isolated light shower is possible (10%) overnight, but unlikely. Shower and thunderstorm chances increase by noon Saturday, when a wetting rain is more likely. ...Thunderstorms imply strong gusty and erratic winds... .TODAY... Sky/weather.........Mostly sunny (45-55 percent) and mostly cloudy (75-85 percent) between 1300 and 1800. CWR.................0 percent. Chance of pcpn......15 percent. Chance of thunder...15 percent. Max temperature.....Around 65. Min humidity........16-19 percent. Wind (20 ft)........Light north-northeast winds until 1200, then southwest around 10 mph with gusts 15 to 20 mph. Gusty and erratic winds possible near thunderstorms in the afternoon. Ridgetop wind.......North around 10 mph until 1100, then west until 1400, then southwest 15 to 20 mph. Mixing height.......2500 ft AGL until 1100. 9500 ft AGL after 1400. Transport winds.....East around 10 mph until 0900, then south 10 to 15 mph until 1400, then southwest 20 to 25 mph. Smoke dispersal.....Poor until 1100 increasing to excellent after 1400. TIME (MDT) 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........50 50 50 50 45 50 50 45 55 80 50 Weather cov..... ISO ISO Weather type.... RW RW Tstm cov........ ISO ISO CWR.............0 0 0 0 0 0 0 0 0 0 0 Chc of pcpn (%).0 0 10 10 10 10 10 10 10 10 10 Chc of thdr (%).0 0 0 0 0 10 10 10 10 10 10 Temp............34 37 41 48 52 55 58 62 63 63 64 RH..............63 60 54 42 34 29 24 20 18 18 20 20 FT wind dir..N NE N NW W SW SW SW SW S SW 20 FT wind spd..5 4 4 3 4 5 6 6 8 12 10 20 FT wind gust.8 8 8 8 8 10 11 12 13 17 14 Ridge wind dir..N NE N NW W SW SW SW SW S SW Ridge wind spd..10 10 10 10 10 10 10 15 15 20 15 Mix hgt (kft)...1.5 1.5 1.5 2.5 3.5 4.5 6.5 9.0 9.5 8.5 8.5 Transp wind dir.E E SE S S S SW S S SW S Transp wind spd.10 9 9 8 10 13 15 20 22 21 21 SDspl kt-ft/100012 11 11 16 31 52 82 152 180 154 157 .TONIGHT... Sky/weather.........Partly cloudy (35-45 percent). Isolated showers and thunderstorms possible in the evening. CWR.................0 percent. Chance of pcpn......20 percent. Chance of thunder...10 percent. Min temperature.....Around 35. Max humidity........70-74 percent. Wind (20 ft)........Southwest winds 8 to 10 mph with gusts to around 15 mph until 1900, then turning southeast around 7 mph by midnight. Gusty and erratic winds possible near thunderstorms. Ridgetop wind.......South 10 to 15 mph until 2200, then northeast until 2400, then southeast. Mixing height.......6000 ft AGL until 1900, then 1500 ft AGL. Transport winds.....South 10 to 15 mph. Smoke dispersal.....Good until 1900, then poor. TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........50 45 45 35 40 35 30 30 35 40 30 25 Weather cov.....ISO ISO ISO ISO Weather type....RW RW RW RW Tstm cov........ISO ISO ISO CWR.............0 0 0 0 0 0 0 0 0 0 0 0 Chc of pcpn (%).20 10 10 10 10 20 10 10 10 10 10 10 Chc of thdr (%).10 10 10 0 0 0 0 0 0 0 0 0 Temp............61 59 55 49 48 46 45 44 43 42 40 39 RH..............23 29 40 48 51 53 57 59 63 66 68 69 20 FT wind dir..SW S S SE N E SE SE SE SE SE SE 20 FT wind spd..7 6 6 6 4 6 7 7 5 5 6 6 20 FT wind gust.13 12 13 12 11 11 10 10 6 6 7 7 Ridge wind dir..SW S S SE N E SE SE SE SE SE SE Ridge wind spd..15 15 10 10 10 10 15 15 10 10 10 10 Mix hgt (kft)...6.0 2.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Transp wind dir.S SW S S S S S S S S S S Transp wind spd.18 13 12 12 9 12 14 14 10 10 12 12 SDspl kt-ft/100098 20 14 14 11 14 16 16 12 12 13 13 .SATURDAY... Sky/weather.........Mostly sunny (40-50 percent). Isolated rain showers in the morning, then rain showers and slight chance of thunderstorms in the afternoon. CWR.................0 percent increasing to 50 percent in the afternoon. Chance of pcpn......80 percent. Chance of thunder...20 percent. Max temperature.....Around 60. Min humidity........36-40 percent. Wind (20 ft)........Southwest winds 10 to 15 mph. Gusts to around 25 mph. Gusty and erratic winds expected near thunderstorms in the afternoon. Ridgetop wind.......Southwest 15 to 20 mph. Mixing height.......2000 ft AGL until 1000. 8500 ft AGL after 1200. Transport winds.....Southwest 15 to 20 mph until 1100, then 25 to 30 mph. Smoke dispersal.....Poor until 1000, increasing to excellent by around 1200. TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........25 30 30 30 35 40 45 50 55 60 60 60 Weather cov.....ISO ISO ISO ISO ISO ISO DEF DEF DEF DEF DEF DEF Weather type....RW RW RW RW RW RW RW RW RW RW RW RW Tstm cov........ SCH SCH SCH SCH SCH SCH CWR.............0 0 0 0 0 0 50 50 50 50 50 50 Chc of pcpn (%).20 20 20 20 20 20 80 80 80 80 80 80 Chc of thdr (%).0 0 0 0 0 0 20 20 20 20 20 20 Temp............38 37 41 45 49 52 55 57 57 57 57 56 RH..............70 68 63 57 50 44 39 38 38 39 38 37 20 FT wind dir..S S S S S SW SW SW SW SW SW SW 20 FT wind spd..8 8 8 9 11 13 14 14 14 13 12 11 20 FT wind gust.12 13 14 16 18 19 21 21 21 20 19 18 Ridge wind dir..S S S S S SW SW SW SW SW SW SW Ridge wind spd..15 15 15 15 20 20 20 20 20 20 20 20 Mix hgt (kft)...1.5 1.5 1.5 2.0 4.5 6.0 7.0 7.5 8.0 8.5 7.5 7.0 Transp wind dir.S S S SW SW SW SW SW SW SW SW SW Transp wind spd.15 15 15 16 21 25 29 30 30 31 29 28 SDspl kt-ft/100017 17 18 28 80 128 181 198 208 227 190 162 .FORECAST DAYS 3 THROUGH 5... .SUNDAY... Partly cloudy. Showers likely and slight chance of thunderstorms. Lows in the lower 30s. Highs in the mid 50s. Southwest winds around 15 mph with afternoon gusts 20 to 25 mph. .MONDAY... Showers, snow showers and slight chance of thunderstorms. Lows around 30. Highs in the upper 40s. West-southwest winds around 10 mph, with gusts around 20 mph. .TUESDAY... Mostly cloudy. Chance of snow showers, showers and slight chance of thunderstorms. Lows in the upper 20s. Highs in the mid 40s. Southwest winds 8 to 10 mph, with gusts around 15 mph. $$ Forecaster...Wittmann Requested by...Paul Hood Type of request...PRESCRIBED .TAG 2609382.1/RIW .DELDT 04/10/26 .FormatterVersion 2.0.0 .EMAIL paul_hood@nps.gov