Alert archive / Hawaii / Winter Storm Warnings in 2026

Winter Storm Warning 4, NWS Honolulu, HI

March 21, 2026Hawaii County, Hawaii

NWS Honolulu, HI issued this winter storm warning at Mar 21, 2026, 8:49 AM HST for Hawaii County, Hawaii. It took effect at Mar 21, 2026, 6:00 PM HST. It was in force for 33 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Mar 21, 2026, 8:49 AM HST (18:49 UTC)
In effect from: Mar 21, 2026, 6:00 PM HST
Expired: Mar 23, 2026, 2:32 AM HST
In force: 33 hr
Issued by: NWS Honolulu, HI

County Hawaii County, HI

The radar

The South Shore radar (PHWA), 57 km from the middle of the area, began a volume at 18:50 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

Lihue, (PHLI), launched 12:00Z, 6.8 hours before the alert went out and 478 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: 276 J/kg
Mixed-layer CIN: -133 J/kg
Mixed-layer LCL: 829 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 24 m²/s²
0-3 km storm-relative helicity: 107 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Honolulu, HI wrote its last area forecast discussion before this winter storm warning went out at Mar 21, 3:29 AM HST, 5 hours 20 minutes earlier.

Area forecast discussion, Mar 21, 3:29 AM HST, 5 hours 20 minutes before

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In the hours before

Special weather statement, Mar 21, 3:42 AM HST, 5 hours 7 minutes before

Special Weather Statement
National Weather Service Honolulu HI
342 AM HST Sat Mar 21 2026

HIZ007-010-011-034>036-211415-
Oahu North Shore HI-Ewa Plain HI-Koolau Windward HI-
Koolau Leeward HI-Waianae Mountains HI-Central Oahu HI-
342 AM HST Sat Mar 21 2026

...A STRONG THUNDERSTORM WILL IMPACT OAHU IN HONOLULU COUNTY THROUGH
415 AM HST...

At 341 AM HST, Doppler radar was tracking a strong thunderstorm
tracking over central Oahu, moving northeast at 35 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Whitmore Village, Waimea Bay, Hauula, Mililani, Waipio, Wahiawa,
Kahana Valley State Park, Schofield Barracks, Turtle Bay, Laie,
Sunset Beach, Kahaluu, Helemano Housing, Kualoa, Kaaawa, Punaluu,
Waimalu, Pupukea, Kunia, and Wheeler Field.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 2166 15792 2163 15793 2155 15784 2152 15784
      2149 15785 2145 15783 2136 15799 2149 15815
      2167 15806 2171 15800 2171 15797
TIME...MOT...LOC 1341Z 236DEG 32KT 2150 15795

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

Gibbs

Special weather statement, Mar 21, 7:29 AM HST, 1 hour 20 minutes before

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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 20, 2:03 PM HST	Areal Flood Advisory	HFO	Kalawao	3 hr
Mar 20, 3:41 PM HST	Winter Storm Watch	HFO	Hawaii	17 hr
Mar 20, 6:25 PM HST	Special Marine Warning	HFO		2 hr
Mar 20, 8:22 PM HST	Special Marine Warning	HFO		113 min
Mar 20, 9:32 PM HST	Special Marine Warning	HFO		29 min
Mar 20, 9:35 PM HST	Areal Flood Advisory	HFO	Kalawao	3 hr
Mar 20, 10:50 PM HST	Small Craft Advisory	HFO		29 hr
Mar 20, 10:51 PM HST	High Surf Advisory	HFO	Honolulu, Kauai	29 hr
Mar 20, 11:34 PM HST	Flash Flood Warning Considerable damage threat	HFO	Kalawao	3 hr
Mar 21, 2:13 AM HST	Areal Flood Advisory	HFO	Kalawao	8 hr
Mar 21, 3:42 AM HST	Special Marine Warning	HFO		2 hr
Mar 21, 3:42 AM HST	Special Weather Statement	HFO	Honolulu	33 min
Mar 21, 4:55 AM HST	Flash Flood Warning	HFO	Honolulu	5 hr
Mar 21, 4:59 AM HST	Areal Flood Advisory	HFO	Kalawao	9 hr
Mar 21, 5:39 AM HST	Special Marine Warning	HFO		2 hr
Mar 21, 6:28 AM HST	Special Marine Warning	HFO		62 min
Mar 21, 7:24 AM HST	Special Marine Warning	HFO		51 min
Mar 21, 7:29 AM HST	Special Weather Statement	HFO		46 min
Mar 21, 8:11 AM HST	Special Marine Warning	HFO		64 min
Mar 21, 9:09 AM HST	Special Marine Warning	HFO		66 min
Mar 21, 9:34 AM HST	Flash Flood Warning	HFO	Kalawao	6 hr
Mar 21, 9:49 AM HST	Areal Flood Advisory	HFO	Kalawao	3 hr
Mar 21, 10:53 AM HST	Special Marine Warning	HFO		97 min
Mar 21, 11:32 AM HST	Flash Flood Warning	HFO	Kalawao	5 hr
Mar 21, 11:45 AM HST	Special Weather Statement	HFO	Kalawao	30 min
Mar 21, 11:57 AM HST	Flash Flood Warning	HFO	Kalawao	12 hr
Mar 21, 12:23 PM HST	Special Marine Warning	HFO		97 min

Nearby

Winter Storm Warnings in Hawaii, 2026 Every winter storm warning in 2026

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.