BILLINGS — A wet midweek pattern will bring increasing thunderstorm coverage and the threat of locally heavy rainfall across south-central Montana, especially near burn scars Wednesday evening. Hotter, drier weather then returns late week, with triple-digit heat likely by Friday and through the weekend.
WEDNESDAY
The most active weather day of the week is expected Wednesday as deep monsoonal moisture combines with an approaching disturbance to produce widespread showers and thunderstorms. Storms are expected to be slow-moving and capable of very heavy rainfall, particularly near the mountains and foothills. A Flood Watch is in effect Wednesday afternoon through early Thursday morning for areas along and south of a Livingston-Columbus-Lodge Grass line. Burn scars, including Robertson Draw, East Side, and Elk, will be especially vulnerable to flash flooding and debris flows. High temperatures will remain seasonable, mainly in the 80s and lower 90s.
THURSDAY
Scattered thunderstorms continue Thursday, though overall moisture will gradually begin to decrease as the midweek disturbance exits the region. Some storms could still produce locally heavy rainfall, especially across southern portions of the area, but the flash flood threat should be less widespread than Wednesday. Temperatures remain near seasonal averages with highs in the mid-80s to lower 90s.
FRIDAY
A shift toward hotter and drier weather develops Friday as a strengthening upper-level ridge builds over the Northern Rockies. Thunderstorm chances decrease considerably, with only isolated high-based storms possible. Afternoon temperatures are expected to climb back into the triple digits in some locations, accompanied by breezy west winds and humidity levels falling into the teens. Fire weather concerns will begin increasing once again.
SATURDAY
The heat intensifies Saturday as the ridge remains firmly in place. Triple-digit temperatures are likely across much of the lower elevations. Dry conditions will dominate, and while winds may not be as strong as Friday, the combination of hot temperatures and low humidity will continue to elevate fire danger. Billings will likely set a new July 25 record high.
SUNDAY
Very warm to hot conditions persist Sunday. Forecast models suggest the ridge may briefly weaken, allowing a weak cold front to approach the region. This could bring slightly cooler temperatures and breezy conditions, though above-normal warmth is still favored. Fire weather concerns will continue to be monitored closely.
MONDAY
Above-normal temperatures remain likely Monday, with generally dry conditions prevailing. A few isolated high-based thunderstorms cannot be ruled out, but the overall pattern continues to favor warm, dry weather and increasing fire danger across the region.
TUESDAY
The long-range pattern continues to support above-average temperatures across the Northern Rockies. Warm to hot conditions are expected to persist with limited precipitation, extending the stretch of midsummer heat into next week.
