Alert archive / Idaho / Flash Flood Warnings in 2023

Flash Flood Warning 42, NWS Pocatello, ID

August 21, 2023Blaine County, Idaho

NWS Pocatello, ID issued this flash flood warning at Aug 21, 2023, 5:28 PM MDT for Blaine County, Idaho. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 21, 2023, 5:28 PM MDT (23:28 UTC)
Expired
Aug 21, 2023, 8:04 PM MDT
In force
3 hr
Issued by
NWS Pocatello, ID
Area
Storm-based polygon
Flood severity
None

County Blaine County, ID

The radar

The Pocatello radar (KSFX), 110 km from the middle of the area, began a volume at 23:32 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Boise Airport, ID (KBOI), launched 12:00Z, 11.5 hours before the alert went out and 180 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Boise Airport, ID at 12:00Z on 2023-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 98 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Boise Airport, ID at 12:00Z on 2023-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 276 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
98 J/kg
Mixed-layer CIN
-88 J/kg
Mixed-layer LCL
853 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
276 m²/s²
0-3 km storm-relative helicity
468 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Pocatello, ID wrote its last area forecast discussion before this flash flood warning went out at Aug 21, 2:15 PM MDT, 3 hours 13 minutes earlier.

Area forecast discussion, Aug 21, 2:15 PM MDT, 3 hours 13 minutes before
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In the hours before

Local storm report, Aug 21, 12:53 PM MDT, 4 hours 35 minutes before
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Local storm report, Aug 21, 1:15 PM MDT, 4 hours 13 minutes before
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Local storm report, Aug 21, 1:24 PM MDT, 4 hours 4 minutes before
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      <h1 id="headline">This service is currently unavailable.</h1>
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Special weather statement, Aug 21, 1:33 PM MDT, 3 hours 55 minutes before
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Special weather statement, Aug 21, 3:14 PM MDT, 2 hours 14 minutes before
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<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.
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Special weather statement, Aug 21, 3:43 PM MDT, 1 hour 45 minutes before
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<head>
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  <title>Service Notice</title>
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</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>
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The office that day

Everything else NWS Pocatello, ID issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 9:02 AM MDTFlash Flood WarningPIHBlaine6 hr
Aug 21, 1:33 PM MDTSpecial Weather StatementPIHBear Lake42 min
Aug 21, 3:14 PM MDTSpecial Weather StatementPIHBonneville31 min
Aug 21, 3:43 PM MDTSpecial Weather StatementPIHBear Lake47 min

Nearby

Flash Flood Warnings in Idaho, 2023Every flash flood warning in 2023

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.