


Area Forecast Discussion
Issued by NWS Billings, MT
Issued by NWS Billings, MT
888 FXUS65 KBYZ 041546 AAA AFDBYZ Area Forecast Discussion...UPDATED National Weather Service Billings MT 946 AM MDT Fri Jul 4 2025 .KEY MESSAGES... - Cooler temperatures Today into Sunday. - 30-60 percent chance showers and thunderstorms this afternoon and evening. Severe thunderstorm chances are low. Not a wash out for fireworks activities. - Scattered strong to severe thunderstorms possible Saturday afternoon and evening. Be weather aware and have plans to seek shelter if storms approach. - Hot and mainly Dry next week, 90s to near 100 Tuesday through Thursday. && .UPDATE... Isolated to widely scattered showers were ongoing over portions of the eastern zones this morning as a weak disturbance lifts through eastern WY/SE MT into the Dakotas. Expect winds to gradually shift around to the north and northeast behind this wave, spreading over the area this afternoon. The next wave, along with upper diffluence is expected to spread over the area this afternoon and evening bringing scattered showers and thunderstorms this afternoon and evening. Convection looks to wind down by 10pm for most areas. Gusty winds are possible with the thunderstorms along with brief heavy rain and small hail, with the greatest threat for any strong storms generally south and west of Billings. Have updated wind and PoPs through the evening to account for latest trends. STP && .DISCUSSION... Through Saturday night... Disturbance ejecting out of the Great Basin will keep low chances for a shower or thunderstorm in the forecast through the early morning hours (4am). There should be a break in activity until 9 or 10 am when another disturbance moves into the south central portion of the forecast area developing scattered showers and a thunderstorm or two over the eastern half of the forecast area through early afternoon. Precipitation accumulations with both of these disturbances will be light (under 0.10 in). Better energy and upper diffluence, along with stronger instability thanks to temperatures reaching the mid to upper 80s, will bring a better chance (30-60%) for showers and thunderstorms to the area from 3 to 10pm Today. Based on NBM precipitation accumulation forecasts, the heaviest precipitation potential looks to be late afternoon into the very early evening (3-7pm), so it does not look to be a wash out for late evening fireworks activity. That said, if storms approach please postpone outdoor activities and head indoors until storms pass. A Pacific trof that has been hanging out over the PacNW for the past few days finally dislodges and pushes through the northern Rockies and into the northern Plains Saturday. Stronger instability and shear will bring the potential for scattered strong to possibly severe thunderstorms Saturday afternoon central and west, and Saturday evening over SE Montana. The HREF is showing numerous stronger helicity tracks along with widespread strong to damaging wind signatures during this time. NCAR Neural Net severe probabilities for Saturday peak in the 20 to 30 percent range for a broad portion of the forecast area, while Updraft Helicity based probabilities are higher in the 30 to 50 percent range for severe thunderstorms. SPC currently shows a marginal risk for Saturday mainly over SE Montana, but based on the latest HREF and NCAR forecasts would anticipate a higher risk category covering more of the forecast area with subsequent issuance`s. Those with outdoor plans Saturday should pay close attention to the weather and have a plan to seek shelter if storms approach. Cooler Pacific air will push highs down int the 70s over the western foothills, with low to mid 80s elsewhere on Saturday. Chambers Sunday through Thursday... Upper trof exits the area to the east on Sunday, with weak westerly flow building into the area behind it. Should be enough residual moisture around to keep a slight chance for afternoon/evening convection in the forecast, but overall not a bad day to get outdoors with highs in the upper 70s to lower 80s. By Monday an upper ridge begins to take hold from the Great Basin north along the spine of the Rockies. This ridging holds through the rest of the forecast period, though there are some hints of a ridge crasher disturbance arriving Thursday afternoon/evening. Under the ridge chances for afternoon and evening thunderstorms drop to under 15% each day and temperatures warm well into the 90s by Tuesday, with a few triple digits possible Wednesday and maybe Thursday too. Chambers && .AVIATION... Isolated to widely scattered showers will affect eastern areas into the early afternoon. Can`t rule out an isolated embedded thunderstorm with this activity. A stronger shortwave and better instability arrives for the afternoon and evening hours with scattered convection moving from the western foothills eastward to encompass the forecast area from 21z-03z time frame, diminishing for most areas by midnight. Strong wind gusts to 45kts will be the main threat with this afternoon and evening convective period. Outside of local MVFR conditions near stronger thunderstorms, VFR conditions will prevail. Chambers/STP && .PRELIMINARY POINT TEMP/POPS... Sat Sun Mon Tue Wed Thu Fri ----------------------------------------------------------- BIL 058/081 055/083 058/087 060/095 063/098 064/094 062/089 47/T 41/U 11/U 10/U 00/U 11/B 11/U LVM 048/076 045/081 049/087 052/093 056/095 056/090 054/087 67/T 21/U 11/U 10/U 00/U 11/U 11/U HDN 058/084 054/083 055/089 058/095 061/098 061/095 061/090 57/T 50/U 11/U 10/U 00/U 11/B 11/U MLS 063/085 057/082 058/087 061/095 064/098 064/096 064/090 55/T 71/U 11/U 10/U 10/U 11/B 11/U 4BQ 061/085 058/081 058/086 061/092 064/095 064/095 063/087 54/T 71/U 21/U 10/U 10/U 11/B 21/U BHK 058/080 054/078 055/084 057/088 060/093 060/092 059/086 44/T 82/W 11/U 10/U 10/U 11/B 21/U SHR 053/083 049/081 052/086 054/092 057/095 058/092 056/085 36/T 41/U 11/U 11/U 00/U 11/B 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$ weather.gov/billings