textproduct: Missoula

DISCUSSION

KEY MESSAGES:

- Showery conditions through Wednesday.

- April showers are out; May flowers (and 70s!) are in. Expect a 10-degree warm up above the seasonal norm by Friday, May 1st, sticking with us through early next week.

- Low probability for isolated thunderstorms this weekend over Divide and/or southern Bitterroot Mountains.

A large upper-level ridge of high pressure currently centered over the Pacific coast will begin shifting eastward today. This transition will bring slightly milder, near-seasonal temperatures to our region. While dry periods are expected, scattered showers will remain possible throughout the morning, becoming more numerous during the afternoon hours. Some patchy fog has formed this morning but will largely lift by mid morning.

As we move toward the end of the week, the strengthening ridge will trigger a notable warming trend, ushering in pleasant spring conditions to start May. By the weekend, high pressure will establish itself over the British Columbia coast, extending its influence across western Montana and north-central Idaho. Although a few weak atmospheric disturbances (shortwaves) tracking south could bring occasional cloud cover or an isolated shower or thunderstorm to the mountains, the overall trend remains warm. Looking ahead to next week, confidence is increasing that warm and dry weather will extend into mid week. Current ensemble models show 90 percent agreement that a low-pressure system will remain well to our south, allowing the warm ridge to persist through Monday and Tuesday.

AVIATION

VFR conditions will generally prevail across the region today, though localized valley fog and low stratus will persist through mid-morning before lifting. KGPI remains the primary concern this morning, as variable visibilities and ceilings have resulted in conditions bouncing between MVFR and LIFR. Expect improvement to VFR at the terminal by 15Z. Shower coverage overall will be less than yesterday, but diurnal heating will trigger scattered afternoon showers, potentially leading to brief MVFR conditions due to showers and localized terrain obscurations. Surface winds will remain light, generally favoring a north to northeasterly flow across all terminals.

MSO WATCHES/WARNINGS/ADVISORIES

MT...None. ID...None.