Alert archive / Hawaii / Flash Flood Warnings in 2021

Flash Flood Warning 9, NWS Honolulu, HI

February 19, 2021Kauai County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Feb 19, 2021, 12:58 PM HST for Kauai County, Hawaii. It was in force for 9 hr. 3 reports 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
Feb 19, 2021, 12:58 PM HST (22:58 UTC)
Expired
Feb 19, 2021, 10:00 PM HST
In force
9 hr
Issued by
NWS Honolulu, HI
Area
Storm-based polygon
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 22:59 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
Feb 19, 2:10 PM HSTFLASH FLOODHanalei, HIKUHIO HIGHWAY CLOSED NEAR HANALEI DUE TO WATER ON THE ROADWAY
Feb 19, 3:40 PM HSTFLASH FLOODHanalei, HIROCK SLIDE NEAR LUMAHAI PARTIALLY BLOCKING KUHIO HWY.
Feb 19, 4:43 PM HSTFLASH FLOODWailua, HIWAILUA MARINA INUNDATED BY FLOOD WATERS

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, 11.0 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 2021-02-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 368 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 2021-02-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939Sfc1 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
368 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
960 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
24 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

923 
WGHW50 PHFO 192258
FFWHFO
HIC007-200200-
/O.NEW.PHFO.FF.W.0009.210219T2258Z-210220T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
1258 PM HST Fri Feb 19 2021

The National Weather Service in Honolulu has issued a

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

* Until 400 PM HST.

* At 1258 PM HST, radar indicated heavy rain over repeatedly forming 
  over the mountains of Kauai, with additional heavy showers and 
  thunderstorms moving in from the east and southeast. Several 
  inches of rain have fallen in the last couple of hours, and 
  already elevated water levels in streams and rivers will rise, 
  likely leading to the closure of Kuhio Highway near Hanalei.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar indicated.

  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.

* Some locations that will experience flash flooding include...
  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.

&&

This warning may need to be extended beyond 400 PM HST if flooding 
persists.

This Flash Flood Warning replaces the previously issued Flood 
Advisory that was in effect for The island of Kauai in Kauai County.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15962 2194 15968 2198 15978 2206 15980
      2216 15974 2224 15958 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...RADAR INDICATED

$$

Birchard
7 follow-up statements
047 
WGHW50 PHFO 192301 CCA
FFWHFO
HIC007-200200-
/O.COR.PHFO.FF.W.0009.210219T2301Z-210220T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning...CORRECTED
National Weather Service Honolulu HI
101 PM HST Fri Feb 19 2021

The National Weather Service in Honolulu has issued a

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

* Until 400 PM HST.

* At 1258 PM HST, radar indicated heavy rain repeatedly forming 
  over the mountains of Kauai, with additional heavy showers and 
  thunderstorms moving in from the east and southeast. Several 
  inches of rain have fallen in the last couple of hours, and 
  already elevated water levels in streams and rivers will rise, 
  likely leading to the closure of Kuhio Highway near Hanalei.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar indicated.

  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.

* Some locations that will experience flash flooding include...
  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.

&&

This warning may need to be extended beyond 400 PM HST if flooding 
persists.

This Flash Flood Warning replaces the previously issued Flood 
Advisory that was in effect for The island of Kauai in Kauai County.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15962 2194 15968 2198 15978 2206 15980
      2216 15974 2224 15958 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...RADAR INDICATED

$$

Birchard
761 
WGHW70 PHFO 200008
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
208 PM HST Fri Feb 19 2021

HIC007-200200-
/O.CON.PHFO.FF.W.0009.000000T0000Z-210220T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
208 PM HST Fri Feb 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 4 PM HST THIS 
AFTERNOON FOR THE ISLAND OF KAUAI IN KAUAI COUNTY...

At 208 PM HST, radar indicated very heavy showers and thunderstorms 
repeatedly forming over the mountains of Kauai, with additional 
heavy showers and thunderstorms affecting other parts of the island. 
Water levels in streams and rivers will continue to rise rapidly as 
runoff works its way down the slopes. Road closures are expected, 
including but not limited to Kuhio Highway near Hanalei.

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

SOURCE...Radar indicated.

IMPACT...Significant and life threatening flooding in drainages,
         streams, rivers, roads, properties, and other low lying
         areas. Multiple public road closures expected, as well
         as landslides in steep terrain.

Some locations that will experience flash flooding include...
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.

&&

This warning may need to be extended beyond 400 PM HST if flooding 
persists.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15962 2194 15968 2198 15978 2206 15980
      2216 15974 2224 15958 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Birchard
970 
WGHW70 PHFO 200047
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
247 PM HST Fri Feb 19 2021

HIC007-200200-
/O.CON.PHFO.FF.W.0009.000000T0000Z-210220T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
247 PM HST Fri Feb 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 4 PM HST THIS 
AFTERNOON FOR THE ISLAND OF KAUAI IN KAUAI COUNTY...

At 247 PM HST, radar indicated heavy showers and thunderstorms 
diminishing in coverage and intensity over southeast Kauai, but a 
strong thunderstorm was dropping very heavy rain over the area from 
Kaumakani to Kekaha to Polihale, with heavy rain also continuing to 
impact the north shore. Water levels in streams and rivers remain 
dangerously high, and Kuhio Highway near Hanalei is closed due to 
water on the roadway.

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

SOURCE...Radar indicated.

IMPACT...Significant and life threatening flooding in drainages,
         streams, rivers, roads, properties, and other low lying
         areas. Multiple public road closures expected, as well
         as landslides in steep terrain.

Some locations that will experience flash flooding include...
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.

&&

This warning may need to be extended beyond 400 PM HST if flooding 
persists.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15962 2194 15968 2198 15978 2206 15980
      2216 15974 2224 15958 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Birchard
834 
WGHW50 PHFO 200144
FFWHFO
HIC007-200500-
/O.EXT.PHFO.FF.W.0009.000000T0000Z-210220T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
344 PM HST Fri Feb 19 2021

The National Weather Service in Honolulu has extended the

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

* Until 700 PM HST.

* At 344 PM HST, radar indicated heavy showers and thunderstorms 
  diminishing in coverage and intensity over Kauai, but water levels 
  in streams and rivers remain dangerously high. Additionally, Kuhio 
  Highway near Hanalei is closed due to water on the roadway. The 
  Wailua River is close to overflowing its banks as runoff continues 
  to work its way down the slopes.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar indicated.

  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.

* Some locations that will experience flash flooding include...
  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.

&&

This warning may need to be extended beyond 700 PM HST if flooding 
persists.

LAT...LON 2222 15933 2216 15930 2215 15928 2205 15932
      2196 15932 2195 15934 2193 15934 2186 15944
      2188 15962 2194 15968 2198 15978 2206 15980
      2216 15974 2224 15958 2222 15952 2225 15949
      2224 15943 2225 15940

FLASH FLOOD...RADAR INDICATED

$$

Birchard
311 
WGHW70 PHFO 200317
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
517 PM HST Fri Feb 19 2021

HIC007-200500-
/O.CON.PHFO.FF.W.0009.000000T0000Z-210220T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
517 PM HST Fri Feb 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 7 PM HST THIS EVENING 
FOR THE ISLAND OF KAUAI IN KAUAI COUNTY...

At 517 PM HST, radar indicated just a few showers moving over Kauai 
from the east, but water levels in streams and rivers remain 
dangerously high, especially in the Hanalei and Wailua Rivers. Kuhio 
Highway remains closed near Hanalei.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar indicated.

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.

Some locations that will experience flash flooding include...
northern and eastern portions 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 700 PM HST if flooding 
persists.

LAT...LON 2224 15958 2222 15952 2225 15949 2224 15943
      2225 15940 2222 15933 2216 15930 2215 15928
      2205 15932 2196 15932 2195 15934 2205 15961

FLASH FLOOD...RADAR INDICATED

$$

Birchard
868 
WGHW50 PHFO 200452
FFWHFO
HIC007-200800-
/O.EXT.PHFO.FF.W.0009.000000T0000Z-210220T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
652 PM HST Fri Feb 19 2021

The National Weather Service in Honolulu has extended the

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

* Until 1000 PM HST.

* At 652 PM HST, radar indicated that the heavy rain has ended. 
  However, water levels in streams and rivers remain elevated due to 
  heavy rainfall from earlier in the day. In addition, Kauai 
  Emergency Management reported that Kuhio Highway near Hanalei 
  remains closed due to water over the roadway.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Emergency management.

  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.

* Some locations that will experience flash flooding include...
  Lihue, Kapaa, Princeville, Kilauea, North Fork Wailua Trails, 
  Wailua Homesteads, Hanalei, Wailua, Moloaa, Anahola, Wainiha, 
  Haena, Na Pali State Park, Wailua River State Park, Kalihiwai, 
  Kealia, Hanamaulu and Puhi.

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 1000 PM HST if flooding 
persists.

LAT...LON 2224 15958 2222 15952 2225 15949 2224 15943
      2225 15940 2222 15933 2216 15930 2215 15928
      2205 15932 2196 15932 2195 15934 2205 15961

FLASH FLOOD...OBSERVED

$$

JELSEMA
678 
WGHW70 PHFO 200755
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
955 PM HST Fri Feb 19 2021

HIC007-200805-
/O.EXP.PHFO.FF.W.0009.000000T0000Z-210220T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kauai HI-
955 PM HST Fri Feb 19 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 10 PM HST THIS EVENING FOR THE 
ISLAND OF KAUAI IN KAUAI COUNTY...

The heavy rain has ended and area streams continue to recede. 
Therefore the Flash Flood Warning will be allowed to expire at 10 PM 
HST. Kauai Emergency Management reported that Kuhio Highway remains 
closed in the vicinity of the Hanalei River bridge however, due to 
flooding earlier in the day. Please continue to heed remaining road 
closures.

LAT...LON 2224 15958 2222 15952 2225 15949 2224 15943
      2225 15940 2222 15933 2216 15930 2215 15928
      2205 15932 2196 15932 2195 15934 2205 15961

$$

JELSEMA

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 18, 2:54 PM HSTSpecial Weather StatementHFOHawaii36 min
Feb 18, 8:40 PM HSTAreal Flood AdvisoryHFOHonolulu97 min
Feb 19, 7:38 AM HSTSpecial Marine WarningHFO112 min
Feb 19, 8:00 AM HSTAreal Flood AdvisoryHFOKauai5 hr
Feb 19, 10:55 AM HSTSpecial Marine WarningHFO2 hr
Feb 19, 11:40 AM HSTAreal Flood AdvisoryHFOHonolulu86 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.