Alert archive / Hawaii / Flash Flood Warnings in 2021

Flash Flood Warning 36, NWS Honolulu, HI

March 29, 2021Kauai County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Mar 29, 2021, 9:53 AM HST for Kauai County, Hawaii. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Mar 29, 2021, 9:53 AM HST (19:53 UTC)
Expired
Mar 29, 2021, 11:56 AM HST
In force
2 hr
Issued by
NWS Honolulu, HI
Area
Storm-based polygon
Flood severity
None

County Kauai County, HI

The nearest sounding before it

Lihue, (PHLI), launched 12:00Z, 7.9 hours before the alert went out and 18 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, Lihue, at 12:00Z on 2021-03-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 36 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lihue, at 12:00Z on 2021-03-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 square meters per square second.193958Sfc1 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
36 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
937 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
51 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

918 
WGHW50 PHFO 291953
FFWHFO
HIC007-292245-
/O.NEW.PHFO.FF.W.0036.210329T1953Z-210329T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
953 AM HST Mon Mar 29 2021

The National Weather Service in Honolulu has issued a

* Flash Flood Warning for...
  The island of Kauai in Kauai County

* Until 1245 PM HST.

* At 953 AM HST, river gages remain high and, with unsettled weather 
  expected across Kauai through this afternoon, flooding may affect 
  any part of the island.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Gauges.

  IMPACT...Flooding in drainages, streams, rivers, roads,
           properties, and other low-lying areas. Public road
           closures possible in some areas. Landslides are
           possible in steep terrain.

* This warning includes the enter island of Kauai.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Stay away from streams, rivers, drainage ditches, and culverts, even 
if they are currently dry.

Do not cross fast flowing or rising water in your vehicle, or on 
foot. Turn around, don't drown.

&&

This warning may need to be extended beyond 1245 PM HST if flooding 
persists.

LAT...LON 2206 15980 2216 15974 2224 15958 2222 15952
      2225 15949 2224 15943 2225 15940 2222 15933
      2216 15930 2215 15928 2205 15932 2196 15932
      2195 15934 2193 15934 2187 15941 2186 15950
      2188 15962 2194 15968 2198 15978

FLASH FLOOD...RADAR INDICATED

$$

LAU
1 follow-up statement
493 
WGHW70 PHFO 292156
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
1156 AM HST Mon Mar 29 2021

HIC007-292206-
/O.CAN.PHFO.FF.W.0036.000000T0000Z-210329T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
1156 AM HST Mon Mar 29 2021

...FLASH FLOOD WARNING IS CANCELLED FOR THE ISLAND OF KAUAI IN KAUAI 
COUNTY...

Flooding is no longer expected to pose a threat. 

LAT...LON 2206 15980 2216 15974 2224 15958 2222 15952
      2225 15949 2224 15943 2225 15940 2222 15933
      2216 15930 2215 15928 2205 15932 2196 15932
      2195 15934 2193 15934 2187 15941 2186 15950
      2188 15962 2194 15968 2198 15978

$$

LAU

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 28, 5:15 PM HSTWind AdvisoryHFOHawaii22 hr
Mar 28, 7:06 PM HSTWinter Weather AdvisoryHFOHawaii32 hr
Mar 29, 8:54 AM HSTFlash Flood WarningHFOKauai3 hr
Mar 29, 12:32 PM HSTFlash Flood WatchHFOKauai20 hr

Nearby

Flash Flood Warnings in Hawaii, 2021Every flash flood warning in 2021

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.