textproduct: Glasgow

KEY MESSAGES

- Temperatures look to warm up for Friday with highs in the 80s and mainly dry conditions. Widely scattered showers or an isolated thunderstorm are possible at night.

- Confidence is growing for a chance for strong to severe thunderstorms Saturday afternoon and evening.

- A second wave of showers and thunderstorms is expected for Sunday along with cooler temperatures.

DISCUSSION

WEATHER PATTERN OVERVIEW:

Warmer temperatures and dry weather are expected for Friday with upper level ridging in place. A weak shortwave will track in from the west for isolated to widely scattered showers and thunderstorms Friday night.

Attention next turns to Saturday afternoon into Saturday night when the next round of strong to severe thunderstorms appears to be in the cards across much of NE Montana. A strong upper level trough will track east with diffluent southwest upper flow over eastern Montana. HREF shows the timing of initiation roughly after 4 PM with storms tracking northeast during the evening hours. Surface CAPE is the strongest, 1500-2000 J/KG near the MT/ND border, along with around 40 kts of 0-6 km shear. Forecast soundings show inverted-v signatures in the area by Saturday afternoon with relatively moist condition above 500mb. Precipitable water values look to range between 1.00 and 1.25 with surface dew points in the 50s to near 60 with southeast low level flow in the east where the greatest risk likely will be. Overall would expect this profile to support multicellular and supercellular structures supportive of large hail, damaging winds, brief heavy rainfall, and frequent lightning.

This trough will shift east on Sunday with lingering showers and thunderstorms along with cooler temperatures. As the trough pushes downstream look for a gradual drying trend Monday into Tuesday with moderating temperatures.

FORECAST CONFIDENCE & DEVIATIONS:

NBM was in charge this forecast cycle which captured expected trends well for the 7 day period. A blend with high resolution model solutions may be appropriate for pops in the next couple of days to better capture mesoscale evolution of expected thunderstorms for Saturday and Sunday.

Confidence is increasing on strong to severe thunderstorms for Saturday afternoon and evening, with the highest risk area from a line through about Glasgow to Jordan eastward to the MT/ND border.

AVIATION

LAST UPDATED: Friday June 5, 2026 at 0545Z.

FLIGHT CAT RANGE: VFR.

DISCUSSION: friday will feature great flying weather with mostly sunny skies unfolding and dry conditions. That said, clouds will increase from the west in the evening with a widely scattered shower possible.

WIND: Light and variable winds will become west to southwest at 5 to 8 kts after 12z, increasing to around 10 kts in the afternoon.

GGW WATCHES/WARNINGS/ADVISORIES

None.