textproduct: Glasgow

DISCUSSION

KEY MESSAGES:

- An arctic high pressure will continue to remain over the area through Saturday night.

- Another strong winter storm with significant snow accumulation is expected now through tomorrow morning. WEATHER PATTERN OVERVIEW:

A round of headline hazard products have been issued to cover multiple winter conditions.

To cover the concerns for the resultant hazardous wind chills, a Cold Weather Advisory and an Extreme Cold Warning remain in place through this afternoon. This is in response to the area remaining on the periphery of an upper level trough and surface arctic high pressure system.

The next organized snow storm comes our way from the Canadian Rockies along an embedded strong low pressure system combining with plentiful moisture riding up and over the US Rockies. Models are in fairly good agreement showing roughly a 30-hour period of snowfall for the region. Locally a wide range of snowfall totals can be expected, with around an inch in the northeast and up to 11 inches in the southwest part of the area. A fairly tight gradient of snowfall totals can be expected for locations in between, showing a possible 3 to 8 inches. To cover these snowfall concerns, a Winter Weather Advisory and a Winter Storm warning have been issued.

Most of these winter conditions will quickly subside tomorrow as the strong low pressure moves away toward the east and warmer high pressure pushes into our region from the west. Temperatures are expected to rebound to much warmer, being aided by a chinook event off the east side of the northern Rockies.

But, areas with more snowfall will obviously take longer to accept the suddenly warmer temperatures on Sunday, and the warm up for these locations will likely be more gradual than is shown the model data.

FORECAST CONFIDENCE & DEVIATIONS:

High confidence in wind chills remaining below zero through Sunday morning for most of the area. There is moderate confidence another Cold Weather Advisory will be needed for tonight into tomorrow for a portion of the area. Moderate to high confidence in snow totals and placement through Saturday morning. Made slight increase to winds through 11 am this morning, and then for local southeast winds around the Glasgow area on Day 2.

AVIATION

LAST UPDATED: 0930Z

FLIGHT CAT RANGE: VFR to near airport shutdown.

DISCUSSION: A very strong winter storm system with multiple impacts will persist through this weekend. MVFR to VFR ceilings will continue through Saturday morning. IFR and VLIFR visibility from a new round of snow is expected to creep into the terminals again around 22 to 12Z this afternoon/evening and will hold steady until about mid-morning Saturday. There is low to moderate confidence of KGDV having visibilities reduced to one mile at times from 03Z to 10Z.

WIND: Northwest from 10 to 20 kts through 18Z, reducing to 7 to 15 kts through 00Z, becoming east at 5 to 13 knots after 03Z.

GGW WATCHES/WARNINGS/ADVISORIES

Winter Storm Warning until 8 AM MST Saturday for Central and Southeast Phillips-Central and Southern Valley-Dawson-Garfield- McCone-Northern Phillips-Petroleum-Prairie-Southwest Phillips- Wibaux.

Cold Weather Advisory until 1 PM MST this afternoon for Central and Southern Valley-Dawson-Eastern Roosevelt-McCone-Northern Phillips-Richland-Western Roosevelt-Wibaux.

Extreme Cold Warning until noon MST today for Daniels-Northern Valley-Sheridan.

Winter Weather Advisory from 2 PM this afternoon to 8 AM MST Saturday for Daniels-Eastern Roosevelt-Northern Valley-Richland- Western Roosevelt.