textproduct: Glasgow

KEY MESSAGES

- Southeast winds will remain persistent through this afternoon, especially along the MT/ND Border.

- Dry weather conditions, seasonable temperatures to continue for the first part of this week with upper ridging.

- Precipitation chances look to increase late in the week by about Thursday or Friday.

DISCUSSION

An upper ridge axis established over northwest Montana is preceded by weak shortwaves in the flow and increasing southeast winds at the surface. Observations at South Sawmill and a few others in and around Fort Peck Lake have shown sustained wind speeds increasing already tonight. Given trends, have nudged the short term wind forecast toward the gustier hires solutions in support of maintaining the Lake Wind Advisory for Fort Peck Lake through noon Monday. After that time, breezy conditions should shift toward the east along the MT/ND border as the ridge axis advances closer to the CWA. Meanwhile, this ridge will help support seasonably mild and dry weather conditions for NE Montana through the middle of the week.

On Thursday, a deep western U.S. trough will translate eastward with a shortwave lobe pinwheeling northeastward across southeast Montana out ahead of it Thursday night and Friday. This will lend dynamic support in conjunction with Pacific moisture to increase precipitation chances for the area Thursday night into the Friday along with markedly cooler temperatures. Thermal profiles however should remain warm enough to support rain, though a little snow may mix in near the Canadian border or higher elevations of the Little Rockies by Friday night as the precipitation ends. Current NBM mean shows an early-bird look at a range of a quarter to a half of an inch of storm total QPF with lesser amounts toward Wibaux.

FORECAST CONFIDENCE & DEVIATIONS:

NBM was largely used in support of the going forecast cycle. However, hires model solutions were used as a nudge to near term winds in support of the Lake Wind Advisory for Fort Peck Lake for Monday. Looking at solid ensemble consensus on ridging bringing about warm and dry conditions for the midweek with the general idea toward cooler and wetter weather late in the week. The timing and details of precipitation placement and amount are still to be refined however given that it is at later time scales.

AVIATION

LAST UPDATED: Monday October 19, 2026 at 400Z.

FLIGHT CAT RANGE: VFR.

DISCUSSION: Approaching upper ridging will guide seasonably mild and dry weather conditions across area terminals for Monday.

WIND: SE winds will increase by 12Z Monday and continue through the day, ranging from 10 to 20 kts with occasional gusts to exceed 25 kts.

LLWS: Low level wind shear is possible around 12Z over the taf sites before mixing allows surface winds to increase later in the morning. Wind shear should diminish after 15Z.

GGW WATCHES/WARNINGS/ADVISORIES

Lake Wind Advisory from 3 AM to noon MDT Monday for Central and Southeast Phillips-Central and Southern Valley-Garfield-McCone- Petroleum.