textproduct: Glasgow

KEY MESSAGES

- Extreme heat warning continues this morning due to poor overnight recovery of temperatures. Cooler weather is expected following today.

- High fire danger continues today due to dry and windy conditions.

- Increasing west to northwest winds today will cause impacts to recreation on Fort Peck Lake.

DISCUSSION

WEATHER PATTERN OVERVIEW:

The persistent upper ridge over the region is beginning to break down with a low pressure system moving across western Canada. Cold front moving into eastern Montana early this morning will bring gusty west winds and a cooling airmass. With temperatures remaining very warm overnight, will continue the extreme heat headlines through the morning. The dry airmass and increasing winds will keep fire weather conditions at critical levels, so Red Flag Warning will also continue. Winds will also be strong enough for Lake Wind Advisory for today. The changing wind conditions, at all levels will bring additional smoke into the region from Washington and Oregon, for reductions of visibility and air quality.

A second cold front will arrive tonight into Monday as a trailing lobe of the upper low moves over the region. This will usher in another drop in temperatures for early in the week offering a relief from the heat and fire weather concerns. There may be an isolated to scattered shower or thunderstorm Sunday night with this, but otherwise look for mostly dry weather into the first part of next week.

Longer term, ensembles begin to show the trough moving downstream as a new ridge becomes established over the Pacific Northwest. This will extend height rises over eastern Montana with northwest flow aloft and moderating temperature toward seasonable averages late week.

FORECAST CONFIDENCE & DEVIATIONS:

While NBM handled the big picture well across the forecast, a blend with NBM90 was used for near term winds this weekend in line with the expected windy conditions supporting the Red Flag and Lake Wind headlines in effect.

AVIATION

Mostly VFR conditions. Overall expect quiet weather today into tonight with the exception of haze from upstream wildfire smoke. This smoke may concentrate enough to bring MVFR visibilities to area starting around 15Z as current HRRR Smoke plumes reach the terminals around this time.

GGW WATCHES/WARNINGS/ADVISORIES

Extreme Heat Warning until noon MDT today for Central and Southeast Phillips-Central and Southern Valley-Garfield-Northern Phillips-Northern Valley-Petroleum-Southwest Phillips.

Red Flag Warning until 9 PM MDT this evening for Dawson/McCone/Prairie/Richland/Wibaux Counties-Fort Peck Reservation and Daniels/Roosevelt/Sheridan Counties-Northern Valley and Northern Phillips Counties-Southern Petroleum and Southern Garfield Counties-The Little Rockies-The Lower Missouri River Breaks including the Charles M Russell National Wildlife Refuge.

Lake Wind Advisory until 6 PM MDT this evening for Central and Southeast Phillips-Central and Southern Valley-Garfield-McCone- Petroleum.

Extreme Heat Warning until 6 PM MDT this evening for Daniels- Dawson-Eastern Roosevelt-McCone-Prairie-Richland-Sheridan- Western Roosevelt-Wibaux.