Alert archive / Hawaii / Flash Flood Warnings in 2021

Flash Flood Warning 13, NWS Honolulu, HI

March 8, 2021Kalawao County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Mar 8, 2021, 10:05 PM HST for Kalawao County, Hawaii. It was in force for 5 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 8, 2021, 10:05 PM HST (08:05 UTC)
Expired
Mar 9, 2021, 3:30 AM HST
In force
5 hr
Issued by
NWS Honolulu, HI
Area
Storm-based polygon
Flood severity
None

County Kalawao County, HI

The radar

The Kamuela/Kohala Apt radar (PHKM), 83 km from the middle of the area, began a volume at 08:07 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, 8.1 hours before the alert went out and 169 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, Hilo, at 00:00Z on 2021-03-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 375 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, Hilo, at 00:00Z on 2021-03-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
375 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
667 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

540 
WGHW50 PHFO 090805
FFWHFO
HIC009-091030-
/O.NEW.PHFO.FF.W.0013.210309T0805Z-210309T1030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
1005 PM HST Mon Mar 8 2021

The National Weather Service in Honolulu has issued a

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

* Until 1230 AM HST.

* At 1005 PM HST, radar indicated heavy rain over East Maui, from 
  Haiku to Hana to Kaupo, which includes the area upslope of the 
  Kaupakalua Dam. Rain was falling at a rate of 1 to 2 inches per 
  hour and area streams are on the rise. Oheo Gulch has risen above 
  a level that can produce serious flash flooding along the slopes 
  of Haleakala from Hamao to Kipahulu. Flash flooding is occurring 
  or expected to begin shortly.

  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...
  Kipahulu, Keanae, Kula, Nahiku, Kaupo, Makawao, Pukalani, Keokea, 
  Huelo, Haliimaile, Haiku-Pauwela, Hana, Pauwela, Paia, Haleakala 
  National Park, Wailua, Kailua, Hamoa and Hookipa Beach Park.

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 1230 AM HST if flooding 
persists.

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

LAT...LON 2094 15638 2096 15634 2095 15624 2087 15613
      2088 15613 2084 15611 2081 15600 2078 15597
      2070 15597 2064 15604 2063 15609 2061 15613
      2062 15619 2057 15630 2057 15636

FLASH FLOOD...RADAR INDICATED

$$

JELSEMA
4 follow-up statements
400 
WGHW70 PHFO 090908
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
1108 PM HST Mon Mar 8 2021

HIC009-091030-
/O.CON.PHFO.FF.W.0013.000000T0000Z-210309T1030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maui HI-
1108 PM HST Mon Mar 8 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 AM HST TUESDAY 
FOR THE ISLAND OF MAUI IN MAUI COUNTY...

At 1108 PM HST, radar continued to indicate heavy rain over East 
Maui, from Haiku to Hana to Kaupo, which includes the area upslope 
of the Kaupakalua Dam. Rain was falling at a rate of 1 to 2 inches 
per hour and area streams are running very high. Oheo Gulch remains 
at a level that can produce serious flash flooding along the slopes 
of Haleakala from Hamao to Kipahulu. Additional heavy rainfall is 
developing just offshore East Maui, and is expected to move onshore 
during the next couple hours.

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...
  Kipahulu, Keanae, Kula, Nahiku, Kaupo, Makawao, Pukalani, Keokea, 
  Huelo, Haliimaile, Haiku-Pauwela, Hana, Pauwela, Paia, Haleakala 
  National Park, Wailua, Kailua, Hamoa and Hookipa Beach Park.

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 1230 AM HST if flooding 
persists.

LAT...LON 2094 15638 2096 15634 2095 15624 2087 15613
      2088 15613 2084 15611 2081 15600 2078 15597
      2070 15597 2064 15604 2063 15609 2061 15613
      2062 15619 2057 15630 2057 15636

FLASH FLOOD...RADAR INDICATED

$$

JELSEMA
058 
WGHW50 PHFO 091020
FFWHFO
HIC009-091330-
/O.EXT.PHFO.FF.W.0013.000000T0000Z-210309T1330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
1220 AM HST Tue Mar 9 2021

The National Weather Service in Honolulu has extended the

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

* Until 330 AM HST.

* At 1220 AM HST, radar continued to indicate heavy rain over East 
  Maui, from Haiku to Hana to Kaupo, which includes the area upslope 
  of the Kaupakalua Dam. Rain was falling at a rate of 1 to 2 inches 
  per hour and area streams are running very high. Oheo Gulch 
  remains at a level that has produced serious flash flooding along 
  the slopes of Haleakala from Hamoa to Kipahulu in the past. 
  Additionally, Hanawi Stream has risen to a level that has produced 
  flooding along the Hana Highway near Nahiku in the past. Heavy 
  rainfall continues to develop just offshore East Maui and is 
  expected to move onshore in the next couple of hours.

  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...
  Kipahulu, Keanae, Kula, Nahiku, Kaupo, Makawao, Pukalani, Keokea, 
  Huelo, Haliimaile, Haiku-Pauwela, Hana, Pauwela, Paia, Haleakala 
  National Park, Wailua, Kailua, Hamoa and Hookipa Beach Park.

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 330 AM HST if flooding 
persists.

LAT...LON 2094 15638 2096 15634 2095 15624 2087 15613
      2088 15613 2084 15611 2081 15600 2078 15597
      2070 15597 2064 15604 2063 15609 2061 15613
      2062 15619 2057 15630 2057 15636

FLASH FLOOD...RADAR INDICATED

$$

JELSEMA
237 
WGHW70 PHFO 091208
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
208 AM HST Tue Mar 9 2021

HIC009-091330-
/O.CON.PHFO.FF.W.0013.000000T0000Z-210309T1330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maui HI-
208 AM HST Tue Mar 9 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM HST EARLY THIS 
MORNING FOR THE ISLAND OF MAUI IN MAUI COUNTY...

At 208 AM HST, radar continued to indicate heavy rain over East 
Maui. The heaviest rain was falling from Haiku to Hana to Kipahulu, 
with rainfall rates of 1 to 2 inches per hour in the heaviest 
showers. Heavy rain is also falling upslope of the Kaupakalua Dam 
and along a large stretch of the Hana Highway. Area streams are 
running very high as well. Heavy rainfall continues to develop just 
offshore of East Maui, and may move onshore and affect locations 
that have already received significant rainfall during the next hour 
or two.

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...
  Kipahulu, Keanae, Kula, Nahiku, Kaupo, Makawao, Pukalani, Keokea, 
  Huelo, Haliimaile, Haiku-Pauwela, Hana, Pauwela, Paia, Haleakala 
  National Park, Wailua, Kailua, Hamoa and Hookipa Beach Park.

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 330 AM HST if flooding 
persists.

LAT...LON 2094 15638 2096 15634 2095 15624 2087 15613
      2088 15613 2084 15611 2081 15600 2078 15597
      2070 15597 2064 15604 2063 15609 2061 15613
      2062 15619 2057 15630 2057 15636

FLASH FLOOD...RADAR INDICATED

$$

JELSEMA
763 
WGHW70 PHFO 091325
FFSHFO

Flash Flood Statement
National Weather Service Honolulu HI
325 AM HST Tue Mar 9 2021

HIC009-091335-
/O.EXP.PHFO.FF.W.0013.000000T0000Z-210309T1330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maui HI-
325 AM HST Tue Mar 9 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 330 AM HST EARLY THIS MORNING 
FOR THE ISLAND OF MAUI IN MAUI COUNTY...

The heavy rain has diminished and area streams are slowly receding. 
Due to the heavy rainfall earlier, minor flooding of low lying and 
poor drainage areas may continue for the next few hours. Significant 
flooding however, is no longer expected to pose a threat. Please 
continue to heed remaining road closures.

A Flash Flood Watch remains in effect until 600 AM HST Wednesday.

LAT...LON 2094 15638 2096 15634 2095 15624 2087 15613
      2088 15613 2084 15611 2081 15600 2078 15597
      2070 15597 2064 15604 2063 15609 2061 15613
      2062 15619 2057 15630 2057 15636

$$

JELSEMA

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 8, 2:42 PM HSTFlash Flood Warning Considerable damage threatHFOKalawao5 hr
Mar 8, 8:07 PM HSTHigh Surf AdvisoryHFOHonolulu, Kalawao19 hr
Mar 8, 9:32 PM HSTAreal Flood AdvisoryHFOKalawao33 min
Mar 8, 10:55 PM HSTAreal Flood AdvisoryHFOKauai6 hr
Mar 9, 5:02 AM HSTAreal Flood AdvisoryHFOHonolulu3 hr
Mar 9, 8:05 AM HSTAreal Flood AdvisoryHFOHonolulu28 min
Mar 9, 8:09 AM HSTSpecial Marine WarningHFO2 hr
Mar 9, 8:22 AM HSTSpecial Weather StatementHFOHonolulu53 min
Mar 9, 8:33 AM HSTFlash Flood WarningHFOHonolulu117 min
Mar 9, 9:15 AM HSTSpecial Weather StatementHFOHonolulu30 min
Mar 9, 9:59 AM HSTSpecial Weather StatementHFOHonolulu61 min
Mar 9, 10:03 AM HSTSpecial Marine WarningHFO54 min
Mar 9, 10:31 AM HSTFlash Flood WarningHFOHonolulu6 hr
Mar 9, 10:55 AM HSTAreal Flood AdvisoryHFOHawaii11 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; radar from the NEXRAD Level II archive.