textproduct: Glasgow

KEY MESSAGES

- Much cooler tonight with lows in the 40s. Temperatures climb through the week, returning to low 90s by Thursday.

- Passing rain showers moving west to east will bring light rain to the region. Rain totals will stay below 0.10 inches.

- Northwest winds this afternoon and evening will cause impacts to recreation on Fort Peck Lake. Lake Wind advisory through 9 PM tonight.

DISCUSSION

WEATHER PATTERN OVERVIEW:

As the upper trough deepens and pushes east out of the region, it continues to push a cooling airmass southeastward. We'll be seeing muchbelow average temperatures this afternoon and tonight with lows in the 40s. An isolated dip into the upper 30s will not be out of the questions, depending on cloud cover. Passing rain showers will continue through the evening as they move east out of the region. Accumulation will overall be light, most locations seeing not much more than a few hundredths, but could be up to 0.10" in some places seeing steadier rainfall and better upper level support.

Longer term, ensembles fully exit the trough to the east by Wednesday allowing a new ridge to establish over the Pacific Northwest. This will slowly extend increasing height rises and lowering RH values over eastern Montana with northwest flow aloft, bringing a steady increase in temps. Highs Thursday will reach up to low 90s and look to last into the beginning of the next week. Friday looks to be the hottest day at this time, but further model runs have been bringing warmer temperatures earlier towards midweek. The current ridge crest looks like it may pass the region around Sunday, which could introduce increased chances for rain thereafter.

FORECAST CONFIDENCE & DEVIATIONS:

Deviations from NBM included ARW and SREF blend for PoPs through this evening. Increased winds for a few hours this afternoon following obs. Used HRRRSmoke data in for Vis, mostly to remove erroneous NBM/GLAMP lowered visibilities.

AVIATION

LAST UPDATE: 1830Z

FLIGHT CAT RANGE: VFR

DISCUSSION: Passing rain showers moving west to east will bring periods of light rain to area terminals. Shower will exit the region by 0z tonight. Drier conditions return for tomorrow.

WIND: Northwest at 15 to 25 kts becoming west at 5 to 10 kts during the night. Northwest winds 10 to 15 kts return after sunrise.

GGW WATCHES/WARNINGS/ADVISORIES

Lake Wind Advisory until 9 PM MDT this evening for Central and Southeast Phillips-Central and Southern Valley-Garfield-McCone- Petroleum.