textproduct: Glasgow

KEY MESSAGES

- Cold temperatures through tonight before a warm up tomorrow

- Increasing confidence in windy conditions through the end of the week.

- Unsettled weather this week, with chances for rain and snow beginning tomorrow night.

DISCUSSION

WEATHER PATTERN OVERVIEW:

An active and dynamic week is in store for the entire region.

Today: Colder temperatures continue today and tonight. A stationary front in central Montana will allow for widespread gusty east winds beginning early this morning and continuing through tonight. Upper level ridging continues to build over the region, becoming more zonal over NE MT through tonight.

Tomorrow: The ridge gradually breaks down as low pressure moves off the coast of New England and high pressure builds off the coast of Baja California giving way for a series of shortwave disturbances. As the upper level flow pattern becomes increasingly more zonal and winds aloft begin to increase, we're going to see warmer temperatures and the start of consistent gusty west winds. Influx of pacific moisture tomorrow night bring chances for rain and snow in the evening and overnight.

Tuesday and Wednesday: Rain and snow chances continue through the day on Wednesday as a low pressure clipper system moves through the area. Total snow accumulation looks to stay below 0.5" with most areas seeing 0.2" or less. Winds will be gusty but snow totals are so low I have very low confidence blowing snow will be impactful enough for a Winter Weather Advisory. There's low end chances for gusts greater than 55 mph in Petroleum and SW Phillips county, but with the current setup, those chances will increase.

Thursday and Friday: Models are beginning to have more agreement on quick moving, potent shortwaves beginning Wednesday night, which is expected to tighten up the pressure gradient. The strongest winds this week are looking to be Thursday in western zones (Phillips county) and Friday in eastern zones (Sheridan county). Thursday afternoon (Phillips county) boasts a brief period with up to 50% chance for wind gusts greater than 55 mph.

Weekend: Drier air moves into the region followed by a backdoor cold front. Lower temperatures are expected by the weekend, with lows in the single digits and wind chills below zero could be possible with the breezy winds.

FORECAST CONFIDENCE & DEVIATIONS: Blended HRRR for day 1 winds. Blended 33% NBM90 for day 2 winds and 25% NBM90 for day 3 winds. Used 50% NBM90 for day 1-3 wind gusts.

Confidence is HIGH in below normal temps through tonight.

Confidence is HIGH in above normal temps on Monday through Thursday.

Confidence is MODERATE in rain-snow occurring on Monday night into Wednesday night. Confidence is LOW on precip type.

Confidence is HIGH in winds reaching High Wind Watch and Warning criteria on Thursday.

AVIATION

LAST UPDATE: 0700Z

FLIGHT CAT RANGE: VFR

DISCUSSION: Clear skies and dry weather through the morning. A band of mid to high clouds moves over the region in the afternoon. SCT to FEW mid level clouds return after 6Z tonight.

SFC WIND: E winds 5 to 10 kts through the morning. Winds increase to 15 to 20 kts after 18Z before decreasing to 5 to 10 kts and veering SW.

GGW WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory until 10 AM MST this morning for Sheridan.