Alert archive / Hawaii / Flash Flood Warnings in 2024

Flash Flood Warning 8, NWS Honolulu, HI

May 9, 2024Kalawao County, Hawaii

NWS Honolulu, HI issued this flash flood warning at May 9, 2024, 5:22 PM HST for Kalawao County, Hawaii. It was in force for 91 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 9, 2024, 5:22 PM HST (03:22 UTC)
Expired: May 9, 2024, 6:53 PM HST
In force: 91 min
Issued by: NWS Honolulu, HI
Area: Storm-based polygon
Flood severity: None

County Kalawao County, HI

The radar

The Molokai radar (PHMO), 24 km from the middle of the area, began a volume at 03:24 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

Hilo, (PITO), launched 00:00Z, 3.4 hours before the alert went out and 261 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: 109 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 889 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 79 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 Honolulu, HI wrote its last area forecast discussion before this flash flood warning went out at May 9, 4:03 PM HST, 1 hour 19 minutes earlier.

Area forecast discussion, May 9, 4:03 PM HST, 1 hour 19 minutes before

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In the hours before

Special weather statement, May 9, 4:51 PM HST, 31 minutes before

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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>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

Everything else NWS Honolulu, HI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 9, 3:46 PM HST	High Wind Warning	HFO	Hawaii	35 hr
May 9, 3:48 PM HST	Areal Flood Advisory	HFO	Honolulu	44 min
May 9, 3:51 PM HST	Winter Storm Warning	HFO	Hawaii	35 hr
May 9, 4:28 PM HST	Areal Flood Advisory	HFO	Kalawao	54 min
May 10, 2:12 AM HST	Areal Flood Advisory	HFO	Honolulu	2 hr
May 10, 2:20 AM HST	Special Marine Warning	HFO		115 min
May 10, 4:10 AM HST	Special Marine Warning	HFO		2 hr
May 10, 4:51 AM HST	Special Marine Warning	HFO		114 min
May 10, 5:02 AM HST	Special Marine Warning	HFO		118 min
May 10, 6:50 AM HST	Special Marine Warning	HFO		38 min
May 10, 12:38 PM HST	Areal Flood Advisory	HFO	Honolulu	117 min
May 10, 12:57 PM HST	Areal Flood Advisory	HFO	Kauai	114 min
May 10, 1:13 PM HST	Special Marine Warning	HFO		2 hr

Nearby

Flash Flood Warnings in Hawaii, 2024 Every flash flood warning in 2024

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.