FNUS75 KBYZ 201453 FWSBYZ Spot Forecast for North Derby RX...USFS National Weather Service Billings MT 853 AM MDT Fri Mar 20 2026 Forecast is based on ignition time of 0800 MDT on March 23. If conditions become unrepresentative...contact the National Weather Service. Please contact our office if you have questions or concerns with this forecast. .DISCUSSION... The CWR for Saturday evening's cold front has slightly increased to 50%. There is about a 25% for at least a quarter inch of precip. Min RH values and overnight recoveries have trended slightly lower for Monday and Tuesday. Ridgetop winds will begin to increase Tuesday night to 45 to 60 mph from the west. There is still some uncertainty in exact timing but there are signs for a potential cold front sometime Wednesday evening through Thurday morning. There is currently about a 40% chance for gusts to 60 mph. There is still a good amount of uncertainty with wind gusts, but a range of 45-65 mph wind gusts are most likely. .MONDAY... Sky/weather.........Mostly cloudy. CWR.................0 percent. Chance of lightning.0 percent. Max temperature.....57-61. Min humidity........19-24 percent. Wind (20 ft)........ Slope/valley.......Southwest winds up to 5 mph early in the morning , then becoming northwest 7 to 10 mph late in the afternoon. Gusts up to 20 mph. Ridgetop...........West around 15 to 20 mph. Mixing height.......Increasing to 4400 ft AGL in the afternoon. Transport winds.....Southwest around 15 mph shifting to the west. TIME (MDT) 9 AM 12 PM 3 PM Sky (%).........2 72 76 Weather cov..... Weather type.... Tstm cov........ Chc of ltng (%).0 0 0 Temp............44 55 58 RH..............33 25 21 20 FT wind......SW 3G10 NE 8G15 NW G917 .MONDAY NIGHT... Sky/weather.........Mostly cloudy. CWR.................0 percent. Chance of lightning.1 percent. Min temperature.....37-41. Max humidity........43-49 percent. Wind (20 ft)........ Slope/valley.......Southwest winds up to 10 mph. Ridgetop...........West 20 to 25 mph. Mixing height.......Decreasing to 700 ft AGL overnight. Transport winds..... TIME (MDT) 6 PM 9 PM MID 3 AM Sky (%).........79 78 67 75 Weather cov..... Weather type.... Tstm cov........ Chc of ltng (%).0 0 0 0 Temp............56 49 46 43 RH..............28 40 45 49 20 FT wind......SW 7G13 W 6G10 SW 5G8 SW5G8 .TUESDAY... Sky/weather.........Mostly cloudy. CWR.................0 percent. Chance of lightning.1 percent. Max temperature.....61-65. Min humidity........28-32 percent. Wind (20 ft)........ Slope/valley.......Southwest winds up to 10 mph. Gusts up to 25 mph in the afternoon. Ridgetop...........Southwest 20 to 25 mph. Mixing height.......Increasing to 4000 ft AGL late afternoon. Transport winds..... TIME (MDT) 6 AM 9 AM NOON 3 PM Sky (%).........77 66 69 72 Weather cov..... Weather type.... Tstm cov........ Chc of ltng (%).0 0 0 0 Temp............42 48 58 63 RH..............53 46 34 30 20 FT wind......SW 6G8 SW 5G10 S 9G19 SW 12G23 $$ Forecaster...Stetzer Requested by...Greg Oyler Type of request...PRESCRIBED .TAG 2606530.1/BYZ .DELDT 03/20/26 .FormatterVersion 2.0.0 .EMAIL gregory.oyler@usda.gov