Special Weather Statement, NWS Missoula, MT

Area Forecast Discussion
National Weather Service Missoula MT
222 PM MDT Sun Jul 17 2016

.DISCUSSION...There is a shortwave approaching the region in
southwesterly flow today that will be the main thunderstorm
producing feature this afternoon. Current high resolution model
guidance show the potential for two waves of thunderstorm today
with the first during this afternoon in north central Idaho and
west central Montana. The second area of thunderstorms may pass
later in the day with a focus farther north through the evening.
There are indications that storms could continue through midnight
north of Interstate 90.

The active southwesterly flow pattern will remain over north
central Idaho and western Montana on Monday so showers and
thunderstorms are forecast to return Monday afternoon. There are
also indications that some of the storms on Monday could be strong
with gusty winds and hail. As of now north central Idaho and into
northwest Montana are forecast to have the most ingredients for
stronger thunderstorms though they are also possible along the
divide.

Tuesday through Thursday pattern will keep a weak frontal
boundary over the Idaho Panhandle and NW Montana resulting in a
slight chance of showers and thunderstorms. Upper level wave
passes through at some point midweek to aid in precip development
in NW Montana. Afterwards, a dry west-to-east zonal flow appears
to establish itself over the northern tier of the US as the
subtropical central US high pressure moves westward. This is a
very typical mid-summer hot and breezy pattern for the northern
Rockies and looks to persist through the remainder of July. /ss

&&

.AVIATION...

The atmosphere is beginning to destabilize this afternoon with
daytime heating and an approaching shortwave. Each run of the HRRR
shows the first area of convection to be a bit more organized and
a little slower on its passage from north central Idaho through
western Montana. The first area of thunderstorms is likely to be
between Grangeville, Salmon, and Butte 17/2100z-17/2300z, followed
by Lookout Pass, Missoula, Deer Lodge 17/2300z-18/0100z, and
finally Libby, Kalispell and Glacier National Park around
18/0100-18/0400z. Cloud cover and a few showers will linger in
northwest Montana and especially through Glacier NP tonight.
Thunderstorms are again forecast to return on Monday and a few of
these could be strong with gusty winds and hail.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>