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KEY MESSAGES

- Chinook winds will bring warmer, snow-melting temperatures to most of NE Montana today.

- A few periods of a light mix of rain and snow are possible later this afternoon/evening and again overnight tonight into Wednesday.

- A High Wind Watch has been issued for Phillips County for Thursday.

DISCUSSION

WEATHER PATTERN OVERVIEW:

Chinook winds off the higher elevations of central and southern Montana have already snuck their way into a few isolated portions of northeast Montana today and are still expected to raise temperatures even warmer throughout the remainder of today. This will easily melt a good portion of the small snow pack remaining this far north. Even though this will add some additional moisture to the lower levels of the atmosphere, there was not any evident sign in the model data that freezing fog would result tonight, especially given that widespread cloud cover is expected to prevail over the region tonight. That being said, it is still worth keeping an eye on the possible development of fog/freezing fog if any patches of sky happen to clear out a bit overnight. With this change of air mass, a few scattered areas of light rain/snow are possible but it will not amount to much. Most likely locations to receive a bit of precip later this afternoon through tonight are most areas not including Central Phillips and Central Valley Counties.

Tuesday and Wednesday, as these two air masses continue to jockey for position over the region, alternating pushes of cold air from the northeast and warmer air from the southwest will dictate where the available moisture will lift and result in some scattered areas of snow and rain. Tuesday, that is expected to be south of MT-Highway 200. Tuesday night into Wednesday morning, that impact is expected to extend northward more into northeast Montana. In both cases, precipitation amounts will be light over the plains and more over the mountainous regions.

Of potentially greater concern later this week, is a period of gusty dangerous winds on Thursday. Over the last few days, the NBM Cron has continued to advertize these stronger winds even out as far as day 5 or 6 in the forecast - which it rarely does. So, it has our attention. For now, the biggest threat for our NE Montana region seems to be over Phillips County, but may include other portions eastward. A High Wind Watch has been issued for Phillips County to address these concerns. Adjustments in area and timing are possible in the next few days.

A moderating return to cooler temperatures is showing up the the model data for later this weekend with some kind of a retrograding cold front and chances for a band of snow through NE Montana on Saturday.

FORECAST CONFIDENCE & DEVIATIONS:

Deviated a bit, using a blend including NBM 90 the stronger expected winds by Thursday. There is emerging excellent consensus among ensembles on this so confidence remains fairly high.

Low confidence continues on precipitation overall given the light, scattered nature and periodic presentation over the next few days.

AVIATION

UPDATE: 1825Z mid-day Monday February 23

FLIGHT CAT RANGE: VFR

DISCUSSION: Chinook winds from the west will bring warming temperatures to NE MT providing some melting of the light snow pack. Also the change in air mass may generate a few pockets of a mix of light rain and/or snow. Confidence is lower than 30% that it would result in much more than a sprinkle or flurry, so these were not included in the prevailing TAF groups for now. Amendments may be needed.

WINDS: Today through this evening, from the WSW around 15 kts with a few stronger gusts. Tonight, from the W around 20 kts. Tuesday morning from the NW around 10 kts.

GGW WATCHES/WARNINGS/ADVISORIES

High Wind Watch from Wednesday evening through Friday morning for Central and Southeast Phillips-Northern Phillips-Southwest Phillips.