BILLINGS — A Severe Thunderstorm Watch is in place for portions of south-central and southeast Montana until 11 PM Sunday night. Expect potential small hail and strong wind gusts up to 65 mph with any intense thunderstorms that may develop.
The primary threat includes strong winds reaching speeds of 65 mph. Showers may also generate gusty winds even in the absence of thunder. Dry conditions will mean that any precipitation accumulation is likely to be less than a tenth of an inch.
After a warm Monday, a frontal passage Monday evening will bring gusty northwest winds but little precipitation. Wind gusts could reach 30-45 mph after sunset. Monday's temperatures are projected to range from the mid-70s in the west to the low 90s in the southeast.
A significant midweek system is set to impact the region, though its precise path remains uncertain. A cooling trend will begin Tuesday, leading to temperatures in the 50s to lower 60s on Wednesday and Thursday, with Wednesday likely being the coolest day.
Heavy snow is likely for mountains above 7,000 feet, with possible accumulations ranging from 1-2 feet, which may affect snow removal operations on the Beartooth Highway. Lower elevations can expect widespread rain, with at least a half inch likely in some areas.
The exact trajectory of the low-pressure system remains unclear. The European model predicts heavy precipitation from a slow-moving low in northern Wyoming, while the GFS model suggests a weaker low moving through eastern Montana, resulting in a drier, shorter event.
Current stream and river levels are elevated due to ongoing snowmelt, with larger rivers expected to remain below flood stage this week. However, smaller streams and areas prone to flooding, especially near burn scars, should be monitored closely.
For Billings, approximately 1.50" of rain is anticipated from Tuesday night, Wednesday through Thursday, but this could change based on the system's actual path.
A secondary wave will keep shower activity through Thursday, regardless of the initial low system's impact. After a brief respite with ridging on Thursday night into Friday, additional Pacific energy will likely bring showers (50-80% chance) from Friday afternoon into the weekend. There is also a chance for a deeper trough or developing low late in the weekend into the following Monday, which could result in another period of moderate to heavy rain with significant uncertainty still present.
Temperatures from Friday through the weekend are expected to be seasonal, mostly in the upper 50s to mid-60s. Snow showers and some accumulation may occur at higher elevations, and little to no snowmelt is anticipated during this period.
