Melstone, MT Weather

Key messages

- Mainly dry with seasonable temperatures through the second half of the week.

- Chance of precipitation begins to increase late Friday into Saturday ahead of a potential weather system.

- A weather system may bring cooler temperatures, precipitation, and windy conditions to the region Sunday into Monday, though uncertainty remains.

Update

Winds are gradually decreasing this evening as a subtle frontal boundary sinks south into the area. As of 7:30 PM MDT, this front is showing up just north of Billings on the Billings weather radar (KBLX). As this front drops through the region this evening, higher atmospheric moisture behind the front will allow dew point temperatures to increase. Then, as surface temperatures cool into the 20s and lower 30s tonight, dew point depressions could approach zero in spots. This, combined with light winds, may allow for patchy fog to develop, especially along the Musselshell and lower Yellowstone River valleys (20 percent chance). Any fog that does develop will lift after sunrise tomorrow, Thursday. Thursday will then be a mild and dry day with high temperatures in the 50s to lower 60s. Winds will also turn out of the northeast to east through the day. LA

Discussion

Through Tuesday:

Breezy westerly winds along the western foothills and near the Dakotas border will decrease into the evening hours. There is a low chance (20% or less) of patchy fog along the Musselshell and lower Yellowstone river valleys late tonight into Thursday morning with dewpoint depressions approaching zero and light winds. Troughing developing along the West Coast and high pressure over the central US will keep mainly dry conditions and seasonable temperatures in place into Friday. Energy advecting in from the southwest brings a return of a low to moderate chance (20-40%) of snow showers to the western mountains late Friday into Saturday. High temperatures are forecast from the 40s to 50s most days, warmest on Saturday.

Heading into early next week (Sunday and Monday), upper troughing and an associated area of low pressure look to move inland into the Rockies, bringing the potential for a return of unsettled conditions to the region. There remains uncertainty in the track of the low, and with that, the potential for cooler temperatures, precipitation amounts and wind. Some ensembles show a more pronounced area of low pressure, tracking it through Wyoming, and with that the potential for more precipitation (rain and mountain snow). While other ensembles show a weaker low, bringing less precipitation, but more wind to the region. Will need to monitor the system over the coming days, but cooler conditions, moderate chances for precipitation (40-60%) and wind are all possible. Drier conditions look to move back into the region for the middle of next week. STP

Aviation

01z Update: There is about a 20% chance for fog/low stratus at KMLS from 09-15Z tonight. Lesser confidence (~10%) exists for KBIL for fog, but VCFG will be included in the TAF for higher confidence of fog along the river valleys. TS

Preliminary point temp/pops

Thu Fri Sat Sun Mon Tue Wed ----------------------------------------------------------- BIL 029/053 032/047 033/056 038/053 038/050 035/055 033/051 00/U 00/E 00/B 04/W 75/W 21/B 11/B LVM 024/054 027/050 032/057 034/050 028/046 027/053 026/051 00/U 00/B 12/W 26/W 85/W 21/B 11/B HDN 023/056 029/053 030/058 034/057 036/052 031/057 029/054 00/U 00/B 00/B 04/W 76/W 31/B 11/B MLS 027/054 032/056 037/056 038/061 040/052 035/054 034/051 10/U 00/B 00/B 01/E 76/W 42/W 11/B 4BQ 027/058 035/057 040/058 039/064 041/048 036/052 035/050 00/U 00/B 00/B 01/E 77/W 52/W 21/B BHK 023/057 026/055 038/061 037/064 037/052 030/053 029/050 00/U 01/N 10/E 11/E 67/W 43/W 21/B SHR 022/058 026/054 033/059 034/058 034/048 030/055 029/053 00/U 00/B 00/U 04/W 87/W 42/W 21/B

Watches, warnings and advisories

MT: None. WY: None.