Special Weather Statement, NWS Salt Lake City, UT

Area Forecast Discussion
National Weather Service Salt Lake City UT
1014 AM MDT Thu Jul 22 2021

.SYNOPSIS...
High pressure near the Four Corners will get suppressed southward
as a trough moves eastward along the Canadian border today. Drier
westerly flow will move into northern Utah for the weekend, while
deep moisture will linger across the south leading to daily
showers and thunderstorms with localized heavy rainfall.

&&

.DISCUSSION...Deep moisture remains across much of the CWA today
but will start to dry out some across northern late today and
overnight as a shortwave trough moves east along the Canadian
border turning our flow westerly across northern Utah. As this
boundary comes across this evening there is a chance for a
consolidated or broken line of thunderstorms from about Ogden
southward to Provo between about 1900 and 2300 this evening. Gusty
winds and locally heavy rain are a concern with these storms.

Farther south the atmosphere is juiced up and the wind flow is
light so any thunderstorms will be slow moving adding to the
potential of flash flooding. After collaborating with WPC, WPC has
extended the slight chance of Excessive Rain Outlook for today to
include the Brian Head and Zion National Park as well as the
Capitol Reef area. The storm motion across the south will be
mainly easterly midday time frame but become more southeasterly
over the Escalante Staircase which is favorable for storms to move
down drainage. Farther west, the winds aloft will be southwesterly
which will make the storm motion towards the northeast which is
not as favorable for flash flooding as far as down drainage
motion, but with the deep moisture and slow motion storms could
release abundant rain in a short period of time. Will be
considering a Flash Flood Watch into Zion for this afternoon and
evening.

&&

.AVIATION...KSLC...Medium confidence that current southerly
winds will indeed switch to northwest in the 20-21z timeframe; with
a 40% chance that winds will instead remain southerly and become
gusty. Periods of gusty and erratic winds are likely around any
shower development after 20z. Also medium confidence of a system
moving through the terminal between 02-05z this evening, bringing
showers accompanied by gusty and erratic winds within a southerly
flow.

Rest of Utah and southwest Wyoming...Showers and thunderstorms are
expected to develop across southern and central Utah, with the best
window for thunderstorms occurring between 18-03z. Precipitation
chances decrease farther north, but outflow from showers and
thunderstorms during the late afternoon into early evening could
result in gusty and erratic winds. VFR conditions are expected
outside of thunderstorms areas where MVFR conditions are possible.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Flash Flood Watch through this evening for UTZ128-129.

WY...None.
&&

SHORT TERM...Struthwolf
AVIATION...Verzella

For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecity

For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php

Hazardous Weather Outlook
National Weather Service Salt Lake City UT
406 AM MDT Thu Jul 22 2021

UTZ101>131-WYZ021-231200-
Great Salt Lake Desert and Mountains-Tooele and Rush Valleys-
Eastern Box Elder County-Northern Wasatch Front-Salt Lake Valley-
Utah Valley-Cache Valley/Utah Portion-Wasatch Back-
Bear Lake and Bear River Valley-Wasatch Mountains I-80 North-
Wasatch Mountains South of I-80-Western Uinta Mountains-
Wasatch Plateau/Book Cliffs-Western Uinta Basin-
Western Millard and Juab Counties-Eastern Juab/Millard Counties-
Central Mountains-Sanpete Valley-Sevier Valley-Castle Country-
San Rafael Swell-Southwest Utah-Lower Washington County-
Zion National Park-Southern Mountains-Upper Sevier River Valleys-
Bryce Canyon Country-South Central Utah-
Capitol Reef National Park and Vicinity-Western Canyonlands-
Glen Canyon Recreation Area/Lake Powell-Southwest Wyoming-
406 AM MDT Thu Jul 22 2021

This Hazardous Weather Outlook is for portions of central Utah...
northern Utah...southern Utah...southwest Utah and southwest
Wyoming.

.DAY ONE...Today and Tonight

Daily showers and thunderstorms will be capable of heavy rain,
gusty winds and small hail each afternoon and evening. Those
planning outdoor activities especially across particularly flood
prone areas of southern Utah should continue to monitor future
forecasts.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Daily showers and thunderstorms will be capable of heavy rain,
gusty winds and small hail each afternoon and evening. Those
planning outdoor activities especially across particularly flood
prone areas of southern Utah should continue to monitor future
forecasts.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information
about observed severe weather to the NWS while following all
local, state, and CDC guidelines.

For more information from NOAA/s National Weather Service visit...
http://weather.gov/saltlakecity

For information on potential road travel impacts visit...
http://www.udottraffic.utah.gov/roadweatherforecast.aspx

<!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>

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
307 PM MDT THU JUL 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0243 PM     FLASH FLOOD      MILFORD                 38.40N 113.02W
07/22/2021                   BEAVER             UT   911 CALL CENTER

            BEAVER COUNTY DISPATCH AND EMERGENCY MANAGEMENT REPORT
            STREET FLOODING WITHIN THE CITY OF MILFORD. IN ADDITION,
            DEBRIS FROM FLOODING WAS REPORTED ON SR-21 NEAR MILFORD.
            MILFORD ASOS REPORTED 1.10 INCHES OF RAIN IN ONE HOUR. IN
            ADDITION THE MILFORD ASOS REPORTED A WIND GUST TO 48 MPH
            WITH THE THUNDERSTORM.

&&

ALEX.DESMET

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
312 PM MDT THU JUL 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0225 PM     FLASH FLOOD      TROPIC                  37.62N 112.09W
07/22/2021                   GARFIELD           UT   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED WATER RUNNING DOWN STREETS IN
            TROPIC.

&&

ALEX.DESMET

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
314 PM MDT THU JUL 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0312 PM     FLASH FLOOD      MILFORD                 38.40N 113.02W
07/22/2021                   BEAVER             UT   EMERGENCY MNGR

            EMERGENCY MANAGEMENT REPORTED FLOODWATER 3 FEET DEEP IN
            DOWNTOWN MILFORD.

&&

ALEX.DESMET

Special Weather Statement
National Weather Service Salt Lake City UT
314 PM MDT Thu Jul 22 2021

UTZ123-125-222200-
Southern Mountains UT-Lower Washington County UT-
314 PM MDT Thu Jul 22 2021

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL WASHINGTON COUNTY UNTIL
400 PM MDT...

At 314 PM MDT, National Weather Service Doppler radar indicated a
strong thunderstorm near Dameron Valley, or 25 miles southeast of
Beaver Dam.

Penny to nickel size hail will be possible.

Locations impacted include...
Dameron Valley and Veyo.

This includes Utah Route 18 between mile markers 16 and 27.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If threatening weather approaches, take shelter in a sturdy building.

Heavy rainfall is also occurring with this storm, and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3727 11368 3737 11375 3743 11361 3732 11354
TIME...MOT...LOC 2114Z 250DEG 6KT 3734 11364

ND