Alert archive / Hawaii / Flash Flood Warnings in 2023

Flash Flood Warning 12, NWS Honolulu, HI

February 18, 2023Hawaii County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Feb 18, 2023, 3:55 AM HST for Hawaii County, Hawaii. It was in force for 21 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: Feb 18, 2023, 3:55 AM HST (13:55 UTC)
Expired: Feb 19, 2023, 1:00 AM HST
In force: 21 hr
Issued by: NWS Honolulu, HI
Area: Storm-based polygon
Flood severity: None

County Hawaii County, HI

The radar

The South Shore radar (PHWA), 57 km from the middle of the area, began a volume at 13:58 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

Lihue, (PHLI), launched 12:00Z, 1.9 hours before the alert went out and 478 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: 325 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 614 m above ground
0-6 km bulk shear: 3 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: -8 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 Feb 17, 8:44 PM HST, 7 hours 11 minutes earlier.

Area forecast discussion, Feb 17, 8:44 PM HST, 7 hours 11 minutes before

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In the hours before

Local storm report, Feb 18, 3:22 AM HST, 33 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 17, 11:30 PM HST	Areal Flood Advisory	HFO	Kalawao	3 hr
Feb 18, 3:29 AM HST	Areal Flood Advisory	HFO	Kalawao	3 hr
Feb 18, 10:08 AM HST	Flash Flood Warning	HFO	Kauai	4 hr

Nearby

Flash Flood Warnings in Hawaii, 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.