Alert archive / Hawaii / Flash Flood Warnings in 2011

Flash Flood Warning 21, NWS Honolulu, HI

May 6, 2011Hawaii County, Hawaii

NWS Honolulu, HI issued this flash flood warning at May 6, 2011, 3:36 PM HST for Hawaii County, Hawaii. It was in force for 97 min. 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: May 6, 2011, 3:36 PM HST (01:36 UTC)
Expired: May 6, 2011, 5:13 PM HST
In force: 97 min
Issued by: NWS Honolulu, HI
Area: Storm-based polygon
Flood severity: None

County Hawaii County, HI

The radar

The Kamuela/Kohala Apt radar (PHKM), 61 km from the middle of the area, began a volume at 01:39 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

Time	Report	Where	Remark
May 6, 4:48 PM HST	FLASH FLOOD	2 N Captain Cook, HI	HIGHWAY 19 NEAR KAINALIU KONA CLOSED DUE TO FLOODING AT 448 PM ON MAY 6TH.

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

The nearest sounding before it

Hilo, (PITO), launched 00:00Z, 1.6 hours before the alert went out and 103 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: 47 J/kg
Mixed-layer CIN: -58 J/kg
Mixed-layer LCL: 1051 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 16 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

797 
WGHW50 PHFO 070136
FFWHFO
HIC001-070430-
/O.NEW.PHFO.FF.W.0021.110507T0136Z-110507T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HONOLULU HI
336 PM HST FRI MAY 6 2011

THE NATIONAL WEATHER SERVICE IN HONOLULU HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  THE BIG ISLAND IN HAWAII COUNTY

* UNTIL 630 PM HST

* AT 324 PM HST...THE RAIN GAGE AT KEALAKEKUA SHOWED HEAVY RAIN 
  FALLING AT 3.40 INCHES PER HOUR. THE AREA OF HEAVY RAIN WAS
  NEARLY STATIONARY.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  KEAHOLE POINT KAILUA-KONA AND HOLUALOA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS FLASH FLOODING IS IMMINENT OR OCCURRING
IN STREAMS...ROADS AND LOW LYING AREAS. MOVE TO HIGHER GROUND NOW.

DO NOT CROSS FAST FLOWING OR RISING WATER IN YOUR VEHICLE OR ON FOOT.
TURN AROUND...DON/T DROWN.

&&

THIS FLASH FLOOD WARNING REPLACES THE FLOOD ADVISORY THAT WAS IN
EFFECT FOR THE ISLAND OF HAWAII COUNTY.

THIS WARNING MAY NEED TO BE EXTENDED BEYOND 630 PM HST IF FLASH
FLOODING PERSISTS.

LAT...LON 1976 15610 1978 15592 1941 15580 1935 15595

$$
CRAIG

1 follow-up statement

833 
WGHW70 PHFO 070313
FFSHFO

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HONOLULU HI
513 PM HST FRI MAY 6 2011

HIC001-070322-
/O.CAN.PHFO.FF.W.0021.000000T0000Z-110507T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
HAWAII COUNTY-
513 PM HST FRI MAY 6 2011

...THE FLASH FLOOD WARNING IS CANCELLED FOR THE ISLAND OF HAWAII
COUNTY...

WEATHER RADAR SHOWED THAT THE HEAVY RAINS ALONG THE KONA COAST HAVE 
ENDED. THUS THE FLASH FLOOD WARNING IS CANCELLED.

LAT...LON 1976 15610 1978 15592 1941 15580 1935 15595

$$
CRAIG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 6, 3:14 PM HST	Areal Flood Advisory	HFO	Hawaii	3 hr
May 7, 3:10 AM HST	Areal Flood Advisory	HFO	Honolulu	73 min

Nearby

Flash Flood Warnings in Hawaii, 2011 Every flash flood warning in 2011

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.