textproduct: Glasgow

KEY MESSAGES

- Widespread rain beginning tonight lasting through Tuesday. Low end chances for seeing a weak thunderstorm tonight.

- Overnight temperatures Sunday and Monday are expected to be near freezing.

- Breezy conditions return tonight. Isolated gusts up to 40 mph will be possible overnight.

DISCUSSION

WEATHER PATTERN OVERVIEW:

Upper troughing over much of the western CONUS will bring well below normal temperatures and widespread precipitation through the beginning of the work week. Precipitation will begin to push east into eastern MT around 3 PM this afternoon and continue through Monday night. By the early evening, gusty shifting winds 15 to 20 mph with gusts to 40 mph are expected following a low pressure system passing through the region. Windy conditions may overlap with a dry slot over southeastern zones tonight into tomorrow morning. This is where the most uncertainty lies, as the location of the dry slot and by extension the timing and location of the low will determine how much precipitation we'll get. Highest totals look to be north of the Missouri River ranging from 0.01"-0.03" in southern Garfield to ~0.25" along HWY2 and upwards of 0.6"-0.8" in northwest Phillips county.

While thunderstorms are unlikely with this system, there is a <15% chance for thunder tonight. As the low pressure moves in, some CAMs indicate wind gusts exceeding 50 mph in the far southeast tonight.

Snow still remains unlikely, however, periods of mixed precipitation near the international border and in the Little Rockers during the nighttime hours is possible.

The upper trough will continue to remain over the area for the next several before breaking down. A warm up looks to return for the weekend. Who's ready for a rollercoaster??

FORECAST CONFIDENCE & DEVIATIONS:

Blended HiRes FV3 and SREF for precip through Monday night. Very good model agreement in a dry slot moving through in the early morning hours on Sunday. There is less agreement on how far north it extends.

A Lake Wind Advisory is likely to be needed for tonight, as winds meeting criteria are marginal right now. I opted to not blend any NBM90 in winds following the update to NBM 5.0 - will have to see how the forecast chances following the next run.

AVIATION

LAST UPDATED: 0730Z

FLIGHT CAT RANGE: VFR today, MVFR tonight

DISCUSSION: Scattered high clouds with increasing cloud cover before a widespread precipitation begins to push east over TAF sites after 0Z tonight. The chance of seeing a weak thunderstorm is 10 to 15 percent, opted to leave it out of TAFs at this time.

WINDS: Light and variable through 18Z followed by gusty, shifting winds 15 to 20 mph with gusts to 40 mph following a low pressure system passing through the region. Winds will be predominantly east through 3Z tomorrow, veering west around 16Z.

FIRE WEATHER

Enhanced fire weather concerns will occur this afternoon with min RH in the 20s in most areas with east to southeast winds. A widespread precipitation event will move in from the west after 3 PM this afternoon and continue through Monday night. Gusty shifting winds 15 to 20 mph with gusts to 40 mph are expected tonight and Sunday as a low pressure system passes through the region. While most areas north of the Missouri River will have wetting rains from this system, a dry slot tonight and Sunday south of the Missouri River will limit rainfall amounts from this system.

GGW WATCHES/WARNINGS/ADVISORIES

None.