textproduct: Missoula

DISCUSSION

- Critical Fire Weather Conditions across Northern Rockies, this afternoon through tonight.

- Choppy wave activity on area lakes this afternoon and evening.

- Relatively cool air mass in place tomorrow through early next week, but summer warmth returns thereafter.

With the ridge of high pressure moving eastward, low elevations will see temperatures rise into the 90s and 100s (F) and will combine with low relative humidity and gusty winds through this evening. As a result, critical fire weather conditions will exist today and tonight, with widespread Red Flag Warnings issued across the Northern Rockies. Please check for the latest local fire restrictions in place during this critical fire weather period. For those recreating on area lakes, particularly Flathead Lake, expect choppy wave activity through late evening.

A much cooler day is expected both Sunday and Monday, with highs only reaching into the 70s. Sunday night into Monday, low temperatures will drop into the 40s, and possibly even the high 30s for high elevation valleys, including but not limited to areas like Dixie, ID.

Some forecast models introduce scattered showers across northwest Montana Sunday night into Monday, mainly along the Canadian border and into Glacier National Park. Given how dry the atmosphere will be leading up to this, any shower activity may initially bring gusty winds before rain actually falls.

Long range ensembles generally agree that a warm high pressure ridge will return to the Northern Rockies around the middle of next week. Models also tend to agree that the next iteration of our summertime ridge will be several degrees cooler than the current ridge.

AVIATION

High density altitude will continue due to heat today. Smoke from area wildfires and increasing west winds aloft will be the main aviation weather impacts over the Northern Rockies for the next 24 hours. A surface cold front will increase wind gusts to 30 knots beginning around 01/2000Z and continue past sunset and finally diminishing after midnight. Smoke from local and regional wildfires is expected to increase Sunday-onward.

MSO WATCHES/WARNINGS/ADVISORIES

MT...Red Flag Warning from 2 PM this afternoon to 9 PM MDT Sunday for Deerlodge/West Beaverhead...East Beaverhead.

Red Flag Warning from 2 PM this afternoon to midnight MDT tonight for Bitterroot...East Lolo...Flathead Reservation... Flathead/Glacier Park...Kootenai...West Lolo.

ID...Red Flag Warning until 8 PM PDT this evening for Palouse/Hells Canyon.