Alert archive / Hawaii / Flash Flood Warnings in 2021

Flash Flood Warning 28, NWS Honolulu, HI

March 12, 2021Kauai County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Mar 12, 2021, 1:39 PM HST for Kauai County, Hawaii. It was in force for 6 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Mar 12, 2021, 1:39 PM HST (23:39 UTC)
Expired
Mar 12, 2021, 7:17 PM HST
In force
6 hr
Issued by
NWS Honolulu, HI
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Kauai County, HI

The radar

The South Kauai radar (PHKI), 23 km from the middle of the area, began a volume at 23:40 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.

What was reported inside it

TimeReportWhereRemark
Mar 12, 1:46 PM HSTFLOOD3 E Princeville, HIOFFICALS ADVISING VOLUNTARY EVACUATION OF HOUSELESS COMMUNITY AT ANINI BEACH PARK.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Lihue, (PHLI), launched 12:00Z, 11.7 hours before the alert went out and 17 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 2021-03-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 476 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 2021-03-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 49 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
476 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
759 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
97 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

107 
WGHW50 PHFO 122339
FFWHFO
HIC007-130245-
/O.NEW.PHFO.FF.W.0028.210312T2339Z-210313T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
139 PM HST Fri Mar 12 2021

The National Weather Service in Honolulu has issued a

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

* Until 445 PM HST.

* At 139 PM HST, radar indicated heavy rain with rates up to 1 inch 
  per hour over Kauai. Emergency managers reported numerous road 
  closures from earlier heavy rainfall over the south and west 
  portions of Kauai. There is also flooding occurring in the Anini 
  area of north Kauai.

  HAZARD...Heavy rain producing life threatening flash flooding.

  SOURCE...Emergency management.

  IMPACT...Significant and life threatening flooding in
           drainages, streams, rivers, roads, properties, and
           other low lying areas. Multiple public road closures
           have occurred.

* Some locations that will experience flash flooding include...
  Lihue, Kapaa, Kalaheo, Kekaha, Princeville, Kilauea, North Fork 
  Wailua Trails, Alakai Swamp Trails, Lawai, Omao, Kokee State Park, 
  Wailua Homesteads, Hanalei, Hanapepe, Wainiha, Na Pali State Park, 
  Koloa, Haena, Waimea and Wailua.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid traveling on roads unless absolutely necessary due to the 
large number of roads affected by flooding impacts.

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.

The heavy rains may cause rock and mudslides in steep terrain areas.

&&

This warning may need to be extended beyond 445 PM HST if flooding 
persists.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15961 2194 15968 2198 15978 2207 15980
      2216 15974 2224 15959 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

KODAMA
3 follow-up statements
100 
WGHW70 PHFO 130140
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
340 PM HST Fri Mar 12 2021

HIC007-130245-
/O.CON.PHFO.FF.W.0028.000000T0000Z-210313T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
340 PM HST Fri Mar 12 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM HST THIS 
AFTERNOON FOR THE ISLAND OF KAUAI IN KAUAI COUNTY...

At 340 PM HST, emergency management reported that flooding problems 
are ongoing. Mudslides have recently occurred in several areas, 
including Lihue, Kalaheo, and Koloa. Rainfall has eased but stream 
and river levels remain high.

HAZARD...Heavy rain producing life threatening flash flooding.

SOURCE...Emergency management.

IMPACT...Significant and life threatening flooding in drainages,
         streams, rivers, roads, properties, and other low lying
         areas. Multiple public road closures have occurred.

Some locations that will experience flash flooding include...
  Lihue, Kapaa, Kalaheo, Kekaha, Princeville, Kilauea, North Fork 
  Wailua Trails, Alakai Swamp Trails, Lawai, Omao, Kokee State Park, 
  Wailua Homesteads, Hanalei, Hanapepe, Wainiha, Na Pali State Park, 
  Koloa, Haena, Waimea and Wailua.

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.

The heavy rains may cause rock and mudslides in steep terrain areas.

&&

This warning may need to be extended beyond 445 PM HST if flooding 
persists.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15961 2194 15968 2198 15978 2207 15980
      2216 15974 2224 15959 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

KODAMA
355 
WGHW50 PHFO 130232
FFWHFO
HIC007-130545-
/O.EXT.PHFO.FF.W.0028.000000T0000Z-210313T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
432 PM HST Fri Mar 12 2021

The National Weather Service in Honolulu has extended the

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

* Until 745 PM HST.

* At 432 PM HST, heavy rainfall has moved off of Kauai. However, 
  river and stream levels remain high and flooding problems are 
  still ongoing. Mudslides have recently occurred in several areas, 
  including Lihue, Kalaheo, and Koloa.

  HAZARD...Heavy rain producing life threatening flash flooding.

  SOURCE...Emergency management.

  IMPACT...Significant and life threatening flooding in
           drainages, streams, rivers, roads, properties, and
           other low lying areas. Multiple public road closures
           have occurred.

* This warning includes the entire 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.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

The heavy rains may cause rock and mudslides in steep terrain areas.

&&

This warning may need to be extended beyond 745 PM HST if flooding 
persists.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15961 2194 15968 2198 15978 2207 15980
      2216 15974 2224 15959 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

KODAMA
976 
WGHW70 PHFO 130517
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
717 PM HST Fri Mar 12 2021

HIC007-130527-
/O.CAN.PHFO.FF.W.0028.000000T0000Z-210313T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
717 PM HST Fri Mar 12 2021

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

The heavy rain has ended. Additional showers are possible through 
the night, but flash flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures in the Koloa 
area.

A Flash Flood Watch remains in effect until 600 PM HST Saturday.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15961 2194 15968 2198 15978 2207 15980
      2216 15974 2224 15959 2222 15952 2225 15949
      2224 15943 2225 15940

$$

TS

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 11, 2:22 PM HSTFlash Flood WarningHFOHonolulu2 hr
Mar 11, 2:46 PM HSTAreal Flood AdvisoryHFOKalawao3 hr
Mar 11, 3:22 PM HSTSpecial Marine WarningHFO22 min
Mar 11, 4:15 PM HSTFlash Flood WarningHFOHonolulu3 hr
Mar 11, 6:09 PM HSTAreal Flood AdvisoryHFOHawaii99 min
Mar 11, 7:35 PM HSTAreal Flood AdvisoryHFOHonolulu81 min
Mar 11, 8:54 PM HSTAreal Flood AdvisoryHFOKalawao6 hr
Mar 12, 12:23 AM HSTSpecial Marine WarningHFO112 min
Mar 12, 2:42 AM HSTAreal Flood AdvisoryHFOKauai2 hr
Mar 12, 3:56 AM HSTSmall Craft AdvisoryHFO10 days
Mar 12, 5:04 AM HSTFlash Flood WarningHFOKauai2 hr
Mar 12, 5:29 AM HSTAreal Flood AdvisoryHFOHonolulu2 hr
Mar 12, 8:49 AM HSTSpecial Marine WarningHFO41 min
Mar 12, 8:51 AM HSTAreal Flood AdvisoryHFOKauai2 hr
Mar 12, 9:45 AM HSTGale WarningHFO6 hr
Mar 12, 11:02 AM HSTFlash Flood Warning Considerable damage threatHFOKauai3 hr
Mar 12, 11:22 AM HSTAreal Flood AdvisoryHFOHonolulu68 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.