textproduct: Glasgow

KEY MESSAGES

- A back door cold front will move through on Thursday afternoon to bring fire weather concerns and lake winds up.

- There is a chance of smoke moving through on Thursday afternoon before clearing out by the nighttime hours.

- There is a slight chance of precipitation in the north on Thursday night, and the next chance of rain is not expected until Sunday evening.

DISCUSSION

WEATHER PATTERN OVERVIEW: Northeast Montana will be in NW flow aloft the next few days between an upper low over Hudson Bay and northern Manitoba and an upper ridge over the Rockies and Pacific NW. On Thursday, a dry cold front is expected to move in from the north. This will bring winds up on Fort Peck Lake, Nelson Reservoir, and Medicine Lake, and will bring critical fire weather conditions south of the Missouri River.

A few CAMs (HRRR and NAMNEST) indicate some elevated CAPE around 200 J/kg on Thursday night, so there is a chance for an isolated shower/thunderstorm along the canadian border.

Friday will be cooler in the north and east while the southwest will have temperatures similar to Thursday being near a quasi- stationary front.

The GFS and ECMWF ensembles are suggesting a flattening of the ridge this weekend as it moves through eastern Montana. At the same time, a frontal boundary will remain quasi-stationary along the southern part of the forecast area so that the north will have highs mainly in the 80s while the south has highs mainly in the 90s.

The latest NBM delays any chances for precipitation until Sunday evening.

FORECAST CONFIDENCE & DEVIATIONS: The only deviation was to PoPs in the north on Thursday night to bring them to slight chance.

There is high confidence in the Lake Wind Advisory for tomorrow.

There is low to moderate confidence of precipitation occurring on Thursday night in the north.

There is moderate confidence of isolated smoke and haze reducing visibility slightly during the late morning through late afternoon on Thursday.

There is high confidence in critical fire weather occurring Thursday afternoon south of the Missouri River.

AVIATION

LAST UPDATE: 1830Z

FLIGHT CAT RANGE: VFR through 16Z. Scattered haze from wildfires after that.

DISCUSSION: Dry conditions are expected through the cycle with a few mid to high clouds. There are wildfires west of the area. There is moderate to high confidence of MVFR visibility occurring from 16Z to 00Z Friday.

WIND: West northwest at 10 to 17 knots with gusts to 23 knots, becoming light and variable after 02Z, becoming northwest at 10 to 20 knots with gusts to 30 knots after 17Z.

GGW WATCHES/WARNINGS/ADVISORIES

Lake Wind Advisory from 9 AM to 7 PM MDT Thursday for Central and Southeast Phillips-Central and Southern Valley-Garfield- McCone-Petroleum.

Red Flag Warning from 11 AM to 7 PM MDT Thursday for Dawson/McCone/Prairie/Richland/Wibaux Counties-Southern Petroleum and Southern Garfield Counties-The Lower Missouri River Breaks including the Charles M Russell National Wildlife Refuge.