Flash Flood Warning 59, NWS Goodland, KS

Area Forecast Discussion
National Weather Service Goodland KS
515 PM MDT Thu Jul 20 2023

.UPDATE...
Issued at 352 PM MDT Thu Jul 20 2023

A Severe Thunderstorm Watch has been issued for Cheyenne, Sherman,
Thomas, Wallace, Logan, Gove, Greeley and Wichita counties for the
evening hours. A Severe Thunderstorm Watch remains in effect for
Eastern Colorado.

The stronger storms that form near Highway 40 have left the area.
Attention now turns to the storms developing and moving east in
Colorado. While storms north of I-70 have struggled, storms south
of I-70 have been producing severe hail. That severe hail threat
is possible as storms enter far Eastern Colorado, but should
diminish as storms move further east. Still watching for mainly a
flooding and damaging wind gust threat as storms continue to
cluster and move towards the Tri-state area. A tornado or two is
still possible and would favor areas south of I-70 and west of KS
Highway 27.

&&

.SHORT TERM...(This evening through Friday)
Issued at 143 PM MDT Thu Jul 20 2023

For the remainder of today, still looking at an impactful weather
event late this afternoon into the evening. There is a chance, that
the convection earlier this morning may inhibit storm potential
later. But with satellite showing clearing skies in Eastern and
Central Colorado and storms forming along the Front Range, the
forecast largely remains the same with two rounds of storms expected
late this afternoon and evening. Also, a strong storm has developed
in Wallace county where cloud cover has been clearing and a thermal
gradient has developed into Eastern Colorado. This will be the main
focus for storm development until the first round of storms arrives.

The first round should reach Eastern Colorado around 4-6pm MT and is
forecasted to have the most impacts. All severe hazards are possible
with effective shear of 50+, MLCAPE 1000+ J/KG, veering hodographs
and DCAPE generally above 1000 J/KG. But similar to yesterday, these
parameters will limit the hail potential to generally an inch or
less unless a supercell develops in which case 2+" is possible.
While parameters are similar to yesterday for winds, there is the
possibility for linear storm modes and bowing segments which could
produce wind gusts in excess of 75 mph. For tornadoes, a linear mode
is suggesting QLCS tornadoes are possible with low LCLs and high
shear. There could also be a supercell mainly along and south of a
Flagler to Cheyenne Wells where clouds are clearing. If a supercell
develops, a tornado would be possible with it. The main inhibitor is
a lack of 0-1km shear and low SRH.

The big threat is the potential for heavy rainfall and flash
flooding. Most of the area has already seen an inch or two of
rainfall either this morning or yesterday leading to more saturated
soil. Forecasts still call for an additional two to three inches
with the remaining two rounds and there is a low chance for 4+
inches. Between the earlier rain and the forecasted rainfall, the
area should see a couple of instance of flash flooding. The threat
could have been higher if the storms were not forecasted to move so
fast. Corfidi downshear vectors of 40+ kts suggest that storms will
not stay over an area for long. However, the high PWATs will lead to
high rainfall rates which will produce the high rainfall
accumulations.

Tonight, there could be lingering showers and storms along outflow
boundaries, but storm activity should move out of the area around 1-
3am CT. Cloud cover will likely linger through the night, but cold
air advection along with the front will allow lows to drop down to
near 60. Fog is also likely to develop across the area with counties
along the Colorado border favored where higher level cloud cover
could clear and allow for better radiational cooling.

Tomorrow, some showers and cloud cover could linger through the
morning hours, but the area should clear out and have mostly sunny
skies by the afternoon hours. With the colder air from the front,
temperatures will still only warm into the 70's and low 80's.

.LONG TERM...(Saturday through Thursday)
Issued at 1239 PM MDT Thu Jul 20 2023

Upper ridge over the Four Corners to start the period will amplify
and expand eastward across the Rockies through early next week.
This will translate to a hot and dry period of the local area.
High temperatures will be well into the 90s by Sunday with a few
triple digit readings likely. Do not really see any break in the
above normal temperatures through the end of the long term period.
The upper ridge does flatten out a bit towards mid week, which may
allow for a few isolated afternoon and evening storms to move out
of Colorado associated with weak shortwaves topping the ridge.
However, most areas will stay dry through the entire long term
period.

&&

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 515 PM MDT Thu Jul 20 2023

For KGLD and KMCK, a large complex of showers and thunderstorms
are expected to move through the forecast area, impacting the
terminals with showers and thunderstorms from taf issuance through
about 09z-12z. Cigs will bounce in between VFR and sub VFR with
visibilities occasionally falling into sub VFR category due to
heavy rainfall and potentially fog once rainfall ends. Winds will
generally be from the east or east-northeast at speeds up to
12kts. During the daytime hours Friday, cigs slowly improve into
VFR category with winds establishing a light south to southwest
direction, speeds under 10kts.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Flood Watch until 2 AM MDT /3 AM CDT/ Friday for KSZ001>003-
     013>015-027>029-041-042.

CO...Flood Watch until 2 AM MDT Friday for COZ090>092.

NE...Flood Watch until 2 AM MDT /3 AM CDT/ Friday for NEZ079>081.

&&

UPDATE...KAK
SHORT TERM...KAK
LONG TERM...024
AVIATION...99

<!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>

<!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>

<!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>