Glenn James
Hawaii Weather Today
Founder and maintainer for 30 years


The latest update to this website was 519am Sunday morning HST


Here are the latest 24-hour precipitation totals (inches) for each of the islands Sunday morning:

0.12  Waipa, Kauai 
0.31  St. Stephens, Oahu
0.99  Honolimaloo, Molokai
0.71  Lanai City, Lanai
0.72  Puu Kukui, Maui
1.24  Pahala, Big Island


The following numbers represent the strongest wind gusts (mph) Sunday morning:

10  Waimea Heights, Kauai – NNE
10  Palehua, Oahu – SW
07   Anapuka, Molokai – NNW
05  Lanai 1,  Lanai – SE 
09  Summit, Maui – SSW 
12  Puuanahulu, Big Island – SE


Hawaii’s Mountains – Here’s a link to the live webcam on the summit of our tallest mountain Mauna Kea (~13,800 feet high) on the Big Island of Hawaii. Here’s the webcam for the (~10,023 feet high) Haleakala Crater on Maui. These webcams are available during the daylight hours here in the islands, and at night whenever there’s a big moon shining down. Also, at night you will be able to see the stars, and the sunrise and sunset too…depending upon weather conditions.

https://weather.gc.ca/data/satellite/goes_gwdisk11_1070_100.jpg

Big Blue…click twice for largest version

 

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A deep area of low pressure far north…with thunderstorms far south

 


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Multi-level clouds moving over the state 

 

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https://radar.weather.gov/ridge/standard/PHKI_loop.gif

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Showers locally

 

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Please open this link to see details on the current Watches, Warnings and Advisories noted above




~~~ Hawaii Weather Narrative ~~~

 

Glenn’s Sunday comments:  I’m here in Vancouver, BC, Canada on a working vacation.

 

>>> Interesting weather web blog – Mauka Showers…How Fast is a Flash Flood in Hawaii?

>>> Highest Temperature Saturday, April 11, 2026 – 92 degrees at Phoenix, AZ
>>> Lowest Temperature Sunday, April 12, 2026 –  10 degrees at Mount Washington, NH

 

Hawaii’s Broad Brush Weather Overview…as of 349m Sunday morning:  Showers and isolated thunderstorms will spread over the western half of the state becoming heavy over central portions of the state through tonight. The heaviest rain bands are anticipated over Oahu and Molokai, and possibly spread westward over Kauai. Because of the latest rainfall over the last few days, flash flooding is possible. Light and variable winds are expected to prevail through the first half of the new week, with light trades returning to the state thereafter.

Weather Details for the Hawaiian Islands…as of 349am Sunday morning:  Latest radar observations have brought another band of showers and thunderstorms into Kauai and rapidly approaches Oahu and Molokai, while continuing to meander northeastward. Much of this activity is stemmed from the broad area of low pressure northwest of the Hawaiian Islands and an associated quasi-stationary trough trickling through the middle of the state. Latest balloon soundings at Hilo and Lihue from 6am, suggest precipitable water values of around 1.82 inches and 1.67 inches, respectively, implying a moisture rich environment remains over the state, courtesy of the abundant tropical moisture continuing to be pulled in over the state.

Model guidance of the GFS and ECMWF remain in fairly strong agreement with the timing of the rain bands, suggesting shower activity will continue to move across the state with the heaviest band developing over Oahu and potentially much of, if not all, of Molokai, though there is some indication that the band may anchor over the Kaiwi Channel between Oahu and Molokai. Showers that do develop over Oahu and portions of Molokai will likely persist for numerous hours, accumulating several inches over rain during that time. Models are hinting, however, that the rain band begin to slowly retrograde shortly thereafter back westward, potentially reaching Kauai tonight, but that remains quite uncertain at this point in time.

Conversely, confidence is increasing that the Big Island will remain largely dry apart from the typical afternoon showers over upslope areas. That said, the current Flood Watch across the entire state continues through Monday afternoon, maintaining the “considerable” tag to account for the many areas that are moisture-laden from rainfall earlier this week, and are now more prone to significant flash flooding impacts. Furthermore, the Big Island remains in the Watch, as any rainfall can still cause issues in areas where the ground is saturated.

In the longer-range, model guidance shows the rain band moving west of Kauai by mid-week, allowing light trades to reestablish thereafter. A more typical trade shower pattern will also return as a result, with showers across windward and mountain areas persisting through the end of the period.

 

Here’s a near real-time Wind Profile of the Pacific Ocean – along with a Closer View of the islands / Here’s the latest Weather Map / Looping Surface Precipitation…through the next 8-days/


Marine Environmental Conditions: A surface trough will linger in the vicinity of the central islands early into the new week, keeping moderate to fresh southeasterly winds to its east, and light and variable winds to its west. This weak surface boundary along with an upper level disturbance moving into the region brings another round of showers and isolated thunderstorms into Monday. As the surface trough lifts north and high pressure to the northeast begins to take over at the surface, gentle to moderate easterly trades will gradually develop across the Hawaiian coastal waters by the end of the upcoming week.

A moderate, short to medium-period north-northwest swell (340 degrees), generated by the formerly-gale force low north-northwest of the Hawaiian islands arrives along north and west facing shores. This will maintain small to moderate surf through the beginning of the week, followed by a decline in northwest swell energy for the rest of the week.

A medium-period, south swell will continue to decline through Monday. By Tuesday, however, a new south swell will arrive, once again providing a boost to surf along south facing shores through mid-week, before gradually subsiding into the weekend. Surf along east facing shores remains below seasonal average, with lighter than average trade winds near and upstream of the islands forecast through the upcoming week.

 

Hurricane Hone brings heavy rain, damaging winds and power outages to Hawaii's Big Island | B99-9 WZBB-FM

 Rainy weather with gusty winds locally


World-wide Tropical Cyclone Activity


>>> Here’s a link to the latest Pacific Disaster Center’s Weather Wall


>>> Atlantic Ocean: There are no active tropical cyclones

>>> Caribbean Sea: There are no active tropical cyclones

>>> Gulf of Mexico: There are no active tropical cyclones

Here’s the link to the National Hurricane Center (NHC)

 

>>> Eastern Pacific: There are no active tropical cyclones

Here’s the link to the National Hurricane Center (NHC)

>>> Central Pacific: There are no active tropical cyclones

Here’s the link to the Central Pacific Hurricane Center (CPHC)

 

>>> Northwest Pacific Ocean:

Tropical Cyclone 04W (Sinlaku)…is located approximately 398 NM east-southeast of Navsta, Guam

https://www.metoc.navy.mil/jtwc/products/04W_120600sair.jpg

 

>>>Southwest Pacific Ocean: There are no active tropical cyclones

>>> North and South Indian Oceans / Arabian Sea: There are no active tropical cyclones



Interesting:  A New Way to Eavesdrop on Ocean Temperature in the Arctic

New research led by scientists at UC San Diego’s Scripps Institution of Oceanography finds that the travel time of underwater sounds traveling across the Arctic Ocean can be used to precisely measure ocean temperature under the region’s sea ice, providing precious data on temperature variability in a rapidly changing environment that is remote and difficult to access. The technique, known as ocean acoustic thermometry, was originally developed by the late Walter Munk and Peter Worcester at Scripps and Carl Wunsch at the Massachusetts Institute of Technology.

The basic principle leveraged by acoustic thermometry is that sound travels faster in warmer water and slower in colder water. The technique uses this relationship to infer the temperature of the water the acoustic signal passes through by measuring the time it takes the sound to travel from one point to another. The researchers tested the method during the 2019-2020 Arctic field season with the joint US-Norwegian Coordinated Arctic Acoustic Thermometry Experiment (CAATEX). The team used six bottom-anchored moorings across a roughly 2,600-kilometer (1,600-mile) path in the Arctic Ocean to transmit and measure acoustic signals every three days. The moorings spanned the Arctic Ocean, from north of Alaska in the west to north of Svalbard in the east, and remained in place for one year.

The experiment aimed to test whether this might be a viable way to measure Arctic Ocean temperature year-round, or if challenges such as the scattering of the sound by the rough undersides of sea ice might render the signals undetectable or impossible to decipher.

Read More at: University of California San Diego

An acoustic sound source manufactured at the Marine Science Development Center for Scripps researcher Matthew Dzieciuch being deployed in the Arctic Ocean from the U.S. Coast Guard Icebreaker Healy. Acoustic systems like these are uniquely able to monitor under the ice where satellites are compromised, and provide an unprecedented look at the changing Arctic environment.