BILLINGS — We continue to track that upper-level low coming in from the west that is slowly making its way toward our area. With it will come ample amounts of atmospheric moisture. In fact, the entire area could see levels surge to 200–250% of normal by Saturday morning.
The current track has the system sliding across central Wyoming this weekend before exiting to the east on Monday. If this track pans out, and there is very good agreement between models that it will, it will give us the best opportunity for a good soaking across the region. Heavy rainfall is likely Friday night through Sunday, with south-central Montana and northern Wyoming seeing a 75% to 100% chance of picking up at least 1 inch of rain. Farther east, chances drop to 30% to 60%. There is also a significant potential for higher totals, with a 40% to 80% chance of reaching 2 inches or more from Rosebud County westward, peaking in and around the Billings area. Because of this, a Flood Watch has been issued for much of the region Friday evening through the day Sunday.
Here are some of the projected totals using a blend of models:
Billings: 1.6-3.4"
Alzada: 1.1-2.3"
Baker: 0.6-1.9"
Big Timber: 2.2-4.3"
Broadus: 1.1-2.6"
Burgess Junction: 1.0-2.6"
Clearmont: 1.3-2.7"
Columbus: 2.3-4.3"
Cooke City: 0.9-2.1"
Crow Agency: 1.5-2.8"
Daisy Pass: 0.9-2.2"
Dayton: 1.0-2.5"
Ekalaka: 0.7-2.0"
Forsyth: 1.4-2.7"
Gardiner: 0.5-2.0"
Hardin: 1.5-2.8"
Harlowton: 2.2-4.0"
Hysham: 1.5-3.0"
Lame Deer: 1.3-2.7"
Livingston: 1.4-3.4"
Lodge Grass: 1.3-2.7"
Miles City: 1.4-2.8"
Ranchester: 1.0-2.5"
Red Lodge: 1.7-3.1"
Roundup: 1.3-2.8"
Sheridan: 1.1-2.7"
Story: 1.2-2.6"
Steady rainfall would bring a significant threat of flash flooding and debris flows across recent burn scars. Those living near those areas should be prepared and have a way to constantly monitor the forecast.
Strong thunderstorms are still possible Friday afternoon and evening from Billings into SE Montana. Sunshine early in the day pushing daytime highs into the low 80s, combined with ample atmospheric moisture, will support heavy rain, hail, and gusty winds. Stay weather-aware if you have plans outdoors.
Not only will the system bring a chance of heavy rainfall across the region, it will also bring a chance for 3–6 inches of snow in the higher levels of area mountains, levels that could potentially fall to around 10,000 feet by Saturday night. A Winter Weather Advisory is unlikely for now for the Beartooth Pass. If one does get issued, Saturday night into Sunday morning would be the timeframe. Prepare for winter conditions if you plan to head that way over the weekend.
Rain will gradually taper off from west to east Sunday night into Monday as the low-pressure system moves into the Northern Plains. Although much drier conditions are expected next week, lingering surface moisture from weekend rainfall could still trigger scattered afternoon and evening showers and storms through the middle of the week.
After warmer daytime temperatures in the mid-70s west to the mid-80s east on Friday, highs will cool generally to the mid-60s across the weekend. Expect highs in the 60s and 70s on Monday before warming into the 70s and 80s for the rest of the week.
Miller Robson
Q2 Morning Meteorologist
miller.robson@ktvq.com
