Flash Flood Watch 32, NWS Grand Junction, CO

Area Forecast Discussion
National Weather Service Grand Junction CO
209 PM MDT Fri Sep 3 2021

.SHORT TERM...(Tonight through Saturday night)
Issued at 142 PM MDT Fri Sep 3 2021

Current satellite imagery shows several areas of low and mid
level clouds generally across the central portions of the forecast
area this afternoon. Radar returns also indicate several clusters
of moderate to strong cells along the Tavaputs/Bookcliffs and
Uncompahgre Plateau in addition to a few showers scattered
elsewhere. Some of the stronger storms have been producing small
hail and brief heavy rainfall. Southwest flow continues this
afternoon as the aformentioned trough moves across to our north.
Expect ongoing precipitation to continue through the early
evening hours when solar heating winds down. Max temperatures
tomorrow will continue a slight warming trend as we reach back up
to near-normal highs. Overnight lows will remain fairly similar
(near normals) to the last few nights. High pressure begins
building over the southwest CONUS tomorrow and will impede much
convective activity as flow turns west-northwesterly.

.LONG TERM...(Sunday through Friday)
Issued at 142 PM MDT Fri Sep 3 2021

A large area of high pressure will remain centered to our west, over
Nevada. To our south, plenty of moisture can be seen but flow around
the high will deflect said moisture and keep it in southern portions
of New Mexico and Arizona. The location of the high pressure will
keep upper level winds from the north (mostly) and fairly light
through Wednesday. By Thursday, the high pressure center will have
shifted to the Four Corners and it's this timeframe when some of the
moisture to the south will try to sneak up under the high pressure.
Guidance is not all that excited and the NBM does keep us mostly dry
with a very slim chance for a quick one off shower or storm over the
higher terrain. Either way, moisture will be limited so any
convection that forms will bring some gusty outflow winds and
that'll be about it. Guidance, heading into the weekend, has some
huge discrepancies with the EC keeping us under the influence of
high pressure while the GFS brings a deep trough into the
Intermountain West tapping into some monsoonal moisture. Plenty of
time to hammer out these details so the gist of the forecast will be
sunny skies, dry conditions, the usual afternoon breezes, and warm
temperatures under high pressure.

&&

.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1131 AM MDT Fri Sep 3 2021

Convection has already started firing with some showers and
storms getting close to KASE and KEGE so included VCTS with some
tempo -TSRA for the afternoon hours. KHDN and possibly KRIL and
KTEX may also see some convection so included VCTS for those TAF
sites as well. Some heavier showers and gusty outflows will be the
biggest concern. Don't expect ILS breakpoints to be reached but
in the off chance they do, they shouldn't last for too long.
Convection will die down once the sun starts going down, leading
to a tranquil night and a calm day tomorrow as high pressure
builds in.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&

SHORT TERM...SS
LONG TERM...TGR
AVIATION...TGR

Hazardous Weather Outlook
National Weather Service Grand Junction CO
124 AM MDT Fri Sep 3 2021

COZ001>014-017>023-UTZ022>025-027>029-041300-
Lower Yampa River Basin-Central Yampa River Basin-
Roan and Tavaputs Plateaus-Elkhead and Park Mountains-
Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor-
Central Colorado River Basin-Grand and Battlement Mesas-
Gore and Elk Mountains/Central Mountain Valleys-
Central Gunnison and Uncompahgre River Basin-
West Elk and Sawatch Mountains-Flat Tops-
Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide-
Northwest San Juan Mountains-Southwest San Juan Mountains-
Paradox Valley/Lower Dolores River-
Four Corners/Upper Dolores River-Animas River Basin-
San Juan River Basin-Southeast Utah-Eastern Uinta Mountains-
Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat-
La Sal and Abajo Mountains-Canyonlands/Natural Bridges-
124 AM MDT Fri Sep 3 2021

This hazardous weather outlook is for eastern Utah and western
Colorado.

.DAY ONE...Today and Tonight

Isolated to scattered showers and thunderstorms will develop this
afternoon, favoring the higher terrain of western Colorado. Gusty
winds, lightning and brief heavy rain will be the main threats.
Activity will diminish overnight resulting in dry conditions.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

A drying and warming trend will commence this weekend and into
early to mid next week as a strong ridge of high pressure builds
over the western states.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1200 PM MDT FRI SEP 3 2021

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

1205 AM     HEAVY RAIN       4 NW GRAND CO ARPT      38.53N 109.50W
09/02/2021  M0.62 INCH       GRAND              UT   TRAINED SPOTTER

            TOTAL RAINFALL ON SEPT 1.

&&

<!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>

Special Weather Statement
National Weather Service Grand Junction CO
324 PM MDT Fri Sep 3 2021

UTZ024-025-032215-
Eastern Uinta Basin UT-Tavaputs Plateau UT-
324 PM MDT Fri Sep 3 2021

...A strong thunderstorm will impact portions of central Uintah
County through 415 PM MDT...

At 324 PM MDT, Doppler radar was tracking a strong thunderstorm 22
miles south of Fort Duchesne, moving east at 20 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of central Uintah
County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3991 10981 4006 10980 4012 10930 3981 10932
TIME...MOT...LOC 2124Z 268DEG 19KT 3998 10972

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Stearns