Glenn James
Hawaii Weather Today
Founder and maintainer for 30 years


The latest update to this website was 505pm Saturday evening


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

0.64  N Wailua Ditch, Kauai 
2.83  Hawaii Kai GC, Oahu
3.22  Honolimaloo, Molokai
1.21  Lanai City, Lanai
2.03  Na Kula, Maui
1.72  Pahala, Big Island


The following numbers represent the strongest wind gusts (mph) Saturday evening:

09  Port Allen, Kauai – NE
07  Oahu Forest NWR, Oahu – SW
28   Makapulapai, Molokai – E
25  Lanai 1,  Lanai – SSE 
28  Maalaea Bay, Maui – SSW 
25  Aipaloa, 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

 

https://cdn.star.nesdis.noaa.gov/GOES18/ABI/SECTOR/tpw/13/GOES18-TPW-13-900x540.gif
A deep area of low pressure north-northwest…with thunderstorms far south


https://cdn.star.nesdis.noaa.gov/GOES18/ABI/SECTOR/hi/GEOCOLOR/20261011440-20261012230-GOES18-ABI-HI-GEOCOLOR-600x600.gif

Multi-level clouds moving over the state from the west-southwest

 

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

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

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

Showers locally

 

https://www.weather.gov/wwamap/png/hfo.png

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




~~~ Hawaii Weather Narrative ~~~

 

Glenn’s Saturday 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 Saturday, April 11, 2026 –  15 degrees near Lutsen, MN

 

Hawaii’s Broad Brush Weather Overview…as of 311pm Saturday:  Showers and isolated thunderstorms will spread over the western half of the state tonight and become heavy over central portions of the state Sunday into Sunday night. Flash flooding is possible. The heaviest rain is currently anticipated over Oahu and Molokai, and possibly Kauai.

>>> Today: areas of light to locally moderate rain.
>>> Heaviest rain to move back into western islands this evening.
>>> Slight chance of thunderstorms over mainly interior Big Island this afternoon.
>>> Focus Sunday through Monday will be over western islands – possibly extending east to Molokai.

Weather Details for the Hawaiian Islands…as of 311pm Saturday afternoon: Satellite indicates abundant high clouds that have limited surface heating and kept interior convection in check over island interiors. Low level clouds indicate persistent troughing draped over Maui County. This boundary supported scattered light showers this morning, but those have dissipated with diurnal warming. About 500 miles southwest of Kauai an extensive band of showers and thunderstorms is seen lifting northeastward toward the island. This activity is maintained by rather weak convergence and abundant tropical moisture.

This moisture rich environment is in the process of returning to the islands, especially over Oahu and Maui County. This activity is estimated to reach the western end of the state around midnight. Upper troughing approaches from the west tonight supporting additional pressure falls and strengthening of low-level convergence further east than the aforementioned band of showers upstream of Kauai. Further supporting this idea is a slight eastward shift with respect to the heavy rain axis. This is perhaps partly due to existing surface troughing drifting further east than anticipated.

Model cross sections are actually impressive with how quickly a deep, convergent frontal structure redevelops over central Hawaii. The front is shown to extend from the surface and tilt northwestward with height until it reaches jet stream level west of the state. An appreciable frontal circulation is also shown to accompany this developing feature, and increases confidence in the idea of development and maintenance of a weak-to-moderately forced axis of heavy rain. Primary forecast uncertainty lies with the position of this heavy rain axis.

Although surface troughing has drifted eastward and settled over Maui County, suspect convergence will tend to reorganize slightly further west as larger scale forcing manifests. Strong surface convergence then establishes over or in the vicinity of Oahu, and slowly drifts westward with time. Several inches of rain is likely over Oahu, and potentially part or all of Molokai. From a forecast accuracy standpoint, there is some concern that the heavy rain band could hang up in the Kaiwi Channel between Oahu and Molokai, but the expectation for a slow westward drift suggests Oahu will ultimately receive several hours of heavy rainfall one way or another.

The heavy rain band potentially reaches Kauai on Sunday night, but that remains quite uncertain at this juncture. On the other hand, confidence is increasing that the Big Island will remain largely dry save for typical afternoon showers over upslope areas. Given the flood response that was observed yesterday, there is concern for significant flash flooding impacts on Sunday especially since yesterday`s rainfall further saturated the ground. The existing Flood Watch is “considerable” and that is where it will stay for the time being.

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 low pressure system that is currently north-northwest of the Hawaiian Islands continues to draw moisture across the area. Showers are continuing across the central and eastern coastal waters, though upper-level support is expected to diminish. A trough will linger in the vicinity of the islands into early next week, however, keeping winds lighter than seasonal average. Additional support for showers and isolated thunderstorms will return to the region by tonight into Sunday.

East of the trough, moderate to fresh southeasterly winds will prevail, while winds west of trough will be light and variable, which may become southerly next week but remain generally light. As southerly winds continue to decline, surf along south-facing shores will return smoother, less choppy conditions. Additionally, the medium-period south swell will gradually decline through the weekend. By Tuesday, however, a new south swell will arrive, once again providing a boost to surf along south facing shores.

A moderate, short to medium-period northwest swell, generated by the gale force low to the northwest will bring a boost to surf along north and west facing shores. Another northwest reinforcement on Sunday will maintain this small to moderate surf through the weekend, followed by a decline in northwest swell energy next week. Surf along east facing shores remains below seasonal average with lighter than average trade winds near and upstream of the islands forecast through next 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 475 NM east-southeast of Navsta, Guam

https://www.metoc.navy.mil/jtwc/products/04W_120000sair.jpg

 

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

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



Interesting:  New Software Could Cut Cooling Energy Use by 25% in Data Centers

Data centers consume millions of homes’ worth of electricity each year, with much of that electricity simply powering the cooling systems that keep the facilities operational. Researchers at Penn State are addressing this inefficiency by using artificial intelligence (AI) to dynamically adjust data centers’ power usage to peak when the weather is favorable and electricity is affordable.

The team developed software, powered by a new physics-based AI learning model, that analyzes real-time climate and economic data to optimize data center cooling. The software works by simulating a virtual data center that serves as a training space for an AI agent — a system that can make highly complex decisions and learn over time. A trained agent can provide cooling recommendations personalized for the climate and economic market of a data center, specifically optimized for a facility’s location.

The new approach is detailed in a paper accepted and set to be presented by the researchers at the IEEE ITherm Conference in May.

Read More: Pennsylvania State University