Severe Thunderstorm Warning 56, NWS Great Falls, MT

Area Forecast Discussion
National Weather Service Great Falls MT
211 PM MDT Thu Aug 20 2020

.SYNOPSIS...

Showers and thunderstorms will track east across the region through
this evening with some storms producing strong winds in addition
to lightning and localized rainfall. Very warm and dry conditions
return for Friday through Monday with some cooling likely by mid
to late next week.

&&

.DISCUSSION...

Rest of Today through Friday...Shortwave trough moving into the
Northern Rockies this afternoon will continue east-northeast
across MT tonight. Thunderstorms development is underway across
the mountains as of early this afternoon and coverage expected to
increase as the shortwave moves east. Greatest instability and
potential for organized storm updrafts with hail and locally heavy
rain, in addition to strong winds will exist early this afternoon
with initial storms, with a transition to more of a widespread
thunderstorm wind threat as storms track east into this evening.
The upper level ridge, centered over the Great Basin/SW US,
quickly rebuilds northward on Friday with SW flow aloft bringing a
return to warm and dry conditions.

Saturday through Thursday...Overall, expect very warm to hot
afternoon temperatures to continue through much of next week. With
weak areas of monsoonal moisture rotating through the region, there
will be the chance for a passing thunderstorm, but no significant
widespread rainfalls are forecast for our region at this time during
the extended period. Brusda

&&

.AVIATION...
Updated 1140 AM MDT Thu Aug 20 2020 (18Z TAF Period)

Thunderstorms should develop early this afternoon initially near
the western and SW MT mountains and track east with increasing
coverage through late this afternoon before exiting the region this
evening. Greatest impact from storms will be strong outflow winds,
though brief MVFR ceilings and rain may impact some some terminals
as well. An elevated layer of smoke/haze covers much the the area
but visibility remains largely greater than 6SM, except in closer
proximity to any local wildland fires. Hoenisch

Refer to weather.gov/zlc for more detailed regional aviation weather
and hazard information.

NOTE: Amendments not scheduled for Ennis (KEKS) due to ongoing
runway closure.

&&

.FIRE WEATHER...

Thunderstorm and lightning coverage will be fairly high through early
this evening. Though wetting rain is anticipated with most storms,
the potential for new lightning starts exists as well as impacts
from strong and erratic outflow winds from thunderstorm activity,
and a Red Flag Warning continues through this evening. Warm, dry
and sunny conditions redevelop on Friday and continue through the
weekend with daytime temperatures and dryness peaking again on
Monday. Nighttime humidity recovery is also likely to become
quite poor at mid to higher elevations again late this weekend. A
weather disturbance moving through SW Canada on Saturday could
bring a period of enhanced afternoon winds with gusts around 25
mph, particularly across portions the plains of north-central MT.
Otherwise, winds look to remain below critical thresholds.

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  54  88  58  91 /  40   0   0   0
CTB  51  86  55  84 /  20   0   0   0
HLN  54  90  56  92 /  30   0   0   0
BZN  51  90  53  94 /  30   0   0   0
WYS  36  84  38  88 /  10   0   0   0
DLN  49  87  50  89 /  10   0   0   0
HVR  57  89  58  95 /  30   0   0   0
LWT  54  86  57  91 /  60   0   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 10 PM MDT this evening Central and
Eastern Lewis and Clark National Forest Areas...Chouteau and
Fergus Counties...Deerlodge/Western Beaverhead National Forest...
Eastern Beaverhead National Forest...Eastern
Glacier/Toole/Central/Eastern Pondera/Liberty...Helena and
Townsend Ranger Districts of the Helena National Forest...Hill
and Blaine Counties...Lewis and Clark National Forest Rocky
Mountain District-Rocky Mountain Front...Lincoln Ranger District
of the Helena National Forest.

&&

http://www.weather.gov/greatfalls

<!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>

<!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>

<!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>