Alert archive / Montana / Flash Flood Warnings in 2023

Flash Flood Warning 10, NWS Great Falls, MT

June 10, 2023Lewis and Clark County, Montana

NWS Great Falls, MT issued this flash flood warning at Jun 10, 2023, 3:18 PM MDT for Lewis and Clark County, Montana. 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: Jun 10, 2023, 3:18 PM MDT (21:18 UTC)
Expired: Jun 10, 2023, 6:30 PM MDT
In force: 3 hr
Issued by: NWS Great Falls, MT
Area: Storm-based polygon
Flood severity: None

County Lewis and Clark County, MT

The radar

The Great Falls radar (KTFX), 85 km from the middle of the area, began a volume at 21:20 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

Great_falls, MT (KTFX), launched 12:00Z, 9.3 hours before the alert went out and 140 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 180 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 704 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 9 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Great Falls, MT wrote its last area forecast discussion before this flash flood warning went out at Jun 10, 1:42 PM MDT, 1 hour 36 minutes earlier.

Area forecast discussion, Jun 10, 1:42 PM MDT, 1 hour 36 minutes before

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In the hours before

Local storm report, Jun 10, 2:47 PM MDT, 31 minutes before

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Local storm report, Jun 10, 2:52 PM MDT, 26 minutes before

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  <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.
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      <p class="small" id="detail">
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Local storm report, Jun 10, 3:10 PM MDT, 8 minutes before

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<head>
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  <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.
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The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 10, 1:22 PM MDT	Flash Flood Warning	TFX	Broadwater, Meagher	3 hr
Jun 10, 2:38 PM MDT	Areal Flood Advisory	TFX	Glacier, Pondera	3 hr
Jun 10, 2:54 PM MDT	Areal Flood Advisory	TFX	Lewis and Clark	3 hr
Jun 10, 3:27 PM MDT	Areal Flood Advisory	TFX	Hill, Liberty	3 hr
Jun 10, 4:18 PM MDT	Areal Flood Advisory	TFX	Glacier	3 hr
Jun 10, 5:54 PM MDT	Special Weather Statement	TFX	Glacier, Liberty, Pondera, Toole	36 min

Nearby

Flash Flood Warnings in Montana, 2023 Every 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.