textproduct: Glasgow

KEY MESSAGES

- Warm and dry weather is expected into the weekend. Warmest temperatures are expected Friday.

- The one big exception to dry is late this afternoon into the night when a disturbance will bring showers and thunderstorms. Some storms across the north could be severe with damaging winds.

- Sunday onward expect cooler temperatures with increasing chances for showers and thunderstorms into the week.

DISCUSSION

WEATHER PATTERN OVERVIEW: The southwest flow will continue across the region today with an upper trough digging over the Pacific Northwest. As a disturbance lifts through the flow, afternoon showers over central Montana will expand slowly eastward into the late afternoon and into northeast Montana by the evening. Wind Gusts currently look to be the main threat with 60+ mph showing up in the HREF Max Wind Gusts. However these gusts appear to moderate out into the evening hours around the time they move into northeast Montana. SPC has a slight risk for severe thunderstorms over north central Montana with a slight risk for the remainder of northeast Montana.

Temperatures will remain warm through Friday with the continued southwest flow into Montana and ridge over the northern plains. Highs may reach the upper 90s in the southeast on Friday which lend to elevated Fire Weather concerns if wind gust can ramp up as well.

Early next week as the upper ridge tilts westward and the west coast trough closes off, another round of showers and thunderstorms is expected across the region. This is the second day for a strong precipitation total signal from Sunday night into Monday night. While these totals could still reduce in further forecasts, currently up to 1 inch is being teased at some locations over these two periods.

FORECAST CONFIDENCE & DEVIATIONS: Deviations from NBM include a NPoP blend of CAMs late this afternoon through roughly 15Z Thursday morning to better capture convective elements. Also, did minor tweaks to MinRH and hourly RH in order to maintain consistency with BYZ's Red Flag tweaks.

There is HIGH confidence in forecast through Friday.

There is MODERATE confidence Saturday to Monday with next wave of rain.

There is LOW confidence from Monday night onward.

/GAH

AVIATION

LAST UPDATED: 1800Z

DISCUSSION: VFR with high to mid level clouds spreading across the region. Showers and thunderstorms will develop to the west of the TAFs and move through KGGW and KOLF in the evening hours, roughly 23-07Z along a frontal passage. KSDY and KGDV have low probabilities of a hit and will be handled with Prob30s if they are high enough chance. Some thunderstorms could become severe with excessively gusty erratic winds.

WIND: SE at 10 to 20 gust 25 kts through the evening. Switching to the W at 10 kts or less post frontal passage from roughly Midnight through Thursday morning. Backing to the SW Thursday afternoon.

LLWS: There may be an hour or two of low level wind shear this evening around a frontal passage and thunderstorm passage timings. This threat should end by 08Z.

GAH

GGW WATCHES/WARNINGS/ADVISORIES

None.