Alert archive / Hawaii / Wind Advisories in 2021

Wind Advisory 15, NWS Honolulu, HI

July 31, 2021Hawaii County, Kalawao County, Hawaii

NWS Honolulu, HI issued this wind advisory at Jul 31, 2021, 8:30 PM HST for Hawaii County, Kalawao County, Hawaii. It took effect at Aug 1, 2021, 6:00 AM HST. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued
Jul 31, 2021, 8:30 PM HST (06:30 UTC)
In effect from
Aug 1, 2021, 6:00 AM HST
Expired
Aug 1, 2021, 5:21 PM HST
In force
11 hr
Issued by
NWS Honolulu, HI

Counties Hawaii County, HI, Kalawao County, HI

The radar

The Kamuela/Kohala Apt radar (PHKM), 57 km from the middle of the area, began a volume at 06:34 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, 6.5 hours before the alert went out and 150 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 2021-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 7 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 2021-08-01The 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
7 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1160 m above ground
0-6 km bulk shear
3 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
-67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

827 
WWHW70 PHFO 010630
NPWHFO

URGENT - WEATHER MESSAGE
National Weather Service Honolulu HI
830 PM HST Sat Jul 31 2021

...WIND ADVISORY FOR PORTIONS OF THE BIG ISLAND MAUI AND LANAI 
DURING THE DAY ON SUNDAY...

.Strong and gusty trade winds will build during the day on 
Sunday. Winds will ease slightly Sunday night and Monday.

HIZ015-018-026-027-042-043-045-046-051-052-011930-
/O.NEW.PHFO.WI.Y.0015.210801T1600Z-210802T0400Z/
Lanai Mauka-Maui Leeward West-Kohala-Big Island Interior-
Lanai Windward-Lanai Leeward-Maui Central Valley North-
Maui Central Valley South-Big Island South-Big Island Southeast-
Including the cities of Lanai City, Lahaina, Kaanapali, Kawaihae,
Waikoloa, Waikii, Puuanahulu, Bradshaw Field, 
Saddle Road Above 5000 feet, Shipwreck Beach, Kaumalapau Harbor, 
Kahului, Maalaea, Ocean View, South Point, and Pahala
830 PM HST Sat Jul 31 2021

...WIND ADVISORY IN EFFECT FROM 6 AM TO 6 PM HST SUNDAY...

* WHAT...Northeast winds 15 to 30 mph with localized gusts over 
  50 mph expected.

* WHERE...Portions of Lanai, Maui, and the Big Island.

* WHEN...From 6 AM to 6 PM HST Sunday.

* IMPACTS...Winds this strong can tear off shingles, knock down
  tree branches, blow away tents and awnings and make it difficult
  to steer, especially for drivers of high profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Watch out for falling tree branches when walking or driving. Make
sure tents and awnings are secure or take them down. Be prepared
for power outages. 

&&

$$
Wroe
2 follow-up statements
750 
WWHW70 PHFO 011320
NPWHFO

URGENT - WEATHER MESSAGE
National Weather Service Honolulu HI
320 AM HST Sun Aug 1 2021

...WIND ADVISORY FOR PORTIONS OF THE BIG ISLAND MAUI AND LANAI...

.Strong and gusty trade winds will build during the day. Winds 
will ease slightly Sunday night and Monday.

HIZ015-018-026-027-042-043-045-046-051-052-020230-
/O.CON.PHFO.WI.Y.0015.210801T1600Z-210802T0400Z/
Lanai Mauka-Maui Leeward West-Kohala-Big Island Interior-
Lanai Windward-Lanai Leeward-Maui Central Valley North-
Maui Central Valley South-Big Island South-Big Island Southeast-
Including the cities of Lanai City, Lahaina, Kaanapali, Kawaihae,
Waikoloa, Waikii, Puuanahulu, Bradshaw Field, 
Saddle Road Above 5000 feet, Shipwreck Beach, Kaumalapau Harbor, 
Kahului, Maalaea, Ocean View, South Point, and Pahala
320 AM HST Sun Aug 1 2021

...WIND ADVISORY REMAINS IN EFFECT UNTIL 6 PM HST THIS EVENING...

* WHAT...Northeast winds 15 to 30 mph with localized gusts over 
  50 mph expected.

* WHERE...Portions of Lanai, Maui, and the Big Island.

* WHEN...From 6 AM to 6 PM HST Sunday.

* IMPACTS...Winds this strong can tear off shingles, knock down 
  tree branches, blow away tents and awnings and make it 
  difficult to steer, especially for drivers of high profile 
  vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Watch out for falling tree branches when walking or driving. Make
sure tents and awnings are secure or take them down. Be prepared
for power outages.

&&

$$
Wroe
621 
WWHW70 PHFO 020321
NPWHFO

URGENT - WEATHER MESSAGE
National Weather Service Honolulu HI
521 PM HST Sun Aug 1 2021

...WIND ADVISORY IS CANCELLED...

HIZ015-018-026-027-042-043-045-046-051-052-020430-
/O.CAN.PHFO.WI.Y.0015.000000T0000Z-210802T0400Z/
Lanai Mauka-Maui Leeward West-Kohala-Big Island Interior-
Lanai Windward-Lanai Leeward-Maui Central Valley North-
Maui Central Valley South-Big Island South-Big Island Southeast-
Including the cities of Lanai City, Lahaina, Kaanapali, Kawaihae,
Waikoloa, Waikii, Puuanahulu, Bradshaw Field, 
Saddle Road Above 5000 feet, Shipwreck Beach, Kaumalapau Harbor, 
Kahului, Maalaea, Ocean View, South Point, and Pahala
521 PM HST Sun Aug 1 2021

...WIND ADVISORY IS CANCELLED...

The strong trade winds have begun to diminish across the area.
Thus the Wind Advisory has been cancelled. 

$$

Burke

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 8:30 PM HSTGale WarningHFO21 hr

Nearby

Wind Advisories in Hawaii, 2021Every wind advisory 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.