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KEY MESSAGES

- Low and mid-level clouds will persist over the area through Thursday night.

- Cold arctic air remains entrenched here through the rest of this week. Cold Weather Advisory in effect until 11 AM Thursday for areas north of the Hi-Line.

- Expect a warm front by Monday.

DISCUSSION

WEATHER PATTERN OVERVIEW:

With multiple embedded disturbances rotating through the western states' cold and large low pressure system, an additional wave of snowfall is moving through central and eastern Montana - allbeit very very slowly. Most of the associated moisture available to this disturbance is being wrung out over the Rocky Mountains, leaving just trace to light amounts of snow for eastern Montana through the next 24 hours. Accumulations will be light enough to not warrant any snow headline products at this time.

Eventually toward the end of the weekend and starting next week, a ridge of high pressure from the south re-builds into the region, allowing warmer than average temperatures to return to NE Montana.

Monday through Tuesday will remain dry and warm ahead of an organized frontal passage.

Toward the middle of next week a large scale tight pressure gradient sets up along the international border and moves south through our region, which would increase chances for stronger winds and additional precipitation, the details of which still need more time to be worked out. FORECAST CONFIDENCE & DEVIATIONS:

Forecast largely followed NBM and WPC guidance this forecast cycle with some slight deviations over the next 24 hours to account for good model agreement in light snowfall through our area.

Confidence is high on the cold arctic air mass remaining in place until at least Friday but low on the timing of when warmer temperatures will move in this weekend and beyond.

AVIATION

LAST UPDATE: 0505Z, Wed night, Feb 18

FLIGHT CAT RANGE: VFR/MVFR

DISCUSSION: Locally, a slow-moving disturbance will keep low and mid level clouds over the area for at least this TAF cycle, and may also include the occasional flurry or period of light snow with little to no accumulation for NE MT TAF sites.

WINDS: Now through Thursday morning, remaining from the NW around 10 to 13 kts. After 18Z, winds will become more light and variable to near calm.

GGW WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory until 11 AM MST Thursday for Daniels- Northern Phillips-Northern Valley-Sheridan.