Good morning and happy Tuesday! Significant rainfall is likely today through Wednesday night as a strong low pressure system tracks into eastern Montana. Today will feature increasing clouds, with increasing shower and thunderstorm activity. Daytime highs will reach the upper 60s to lower 70s in central Montana and the low to mid-80s in eastern Montana.
This evening, scattered severe thunderstorms will develop east of I-15, lasting into the night in eastern Montana. These storms may produce hail and damaging wind gusts.
Then, low pressure tracks just east of the area late tonight into Wednesday, widespread rain will begin to fall, especially by Wednesday morning. A significant band of heavy rain will set up east of I-15, impacting parts of Hill, Fergus, Chouteau, and Judith Basin counties, while steady rain will continue in other areas. Winds will also pick up, with gusts expected to reach 40-50 mph on Wednesday. A High Wind Watch is in effect for Judith Basin and Fergus counties, where west winds could gust up to 60 mph.
Most areas can expect rainfall totals between 1 and 2 inches. Due to the counterclockwise circulation around the low, a northerly flow will develop over central Montana for most of the storm. This will lead to strong upsloping on the northern-facing slopes of the mountain ranges in the region, where rainfall amounts could reach 2 to 4 inches. Conversely, areas west of I-15 will receive considerably less moisture.
A Flash Flood Watch is in effect through Wednesday evening for the Horse Gulch Fire burn scar, as heavy rain poses a risk of flash flooding and debris flows in that vicinity.
By dawn on Thursday morning, the rain is expected to clear out for central Montana, although eastern Montana may still experience some lingering showers. Sunny and pleasant fall weather returns as we approach the end of the work week.
Looking ahead to the weekend, a weak disturbance may bring additional shower chances, but overall, conditions will remain mild and enjoyable.
