The latest update to this website was at 850pm Wednesday (HST)

 

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

0.73  Mount Waialeale, Kauai
0.10  Kahuku, Oahu
0.02  Puu Alii, Molokai
0.00  Lanai
0.07  West Wailuaiki, Maui
0.13  Puho CS, Big Island

>>> There are lots of locations that measure rainfall and winds, here’s a map of all areas for your reference (the map is clickable to zoom in closer)

The following numbers represent the strongest wind gusts (mph) as of Wednesday evening:

31  Port Allen, Kauai
35  Oahu Forest NWR, Oahu
33  Molokai AP, Molokai
30  Lanai 1, Lanai
47  Na Kula, Maui
31  Kawaihae Rd, Big Island

Hawaii’s Mountains – Here’s a link to the live webcams on the summit of our tallest mountain Mauna Kea (~13,800 feet high) on the Big Island of Hawaii, and atop the Haleakala Crater (~10,023 feet) 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

 Thunderstorms in the deeper tropics…cold front far northwest

 

https://www.weather.gov/images/hfo/satellite/Hawaii_IR_loop.gif

High clouds clipping the Big Island and well developed cumulus clouds south 

 

 

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

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

Showers locally 

 

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

 

~~~ Hawaii Weather Narrative ~~~

 

Glenn’s Wednesday comments:  I’m home here in upper Kula, Maui, Hawaii.

It’s mostly clear with a few clouds here in Maui County early this morning. The low temperature at my place was 54.5 degrees…with a relative humidity of 80%.

855am, yet another great start to this late summer morning!

245pm, a large area of thunderstorms are firing off to the south of the state…which will at least send some high clouds our way.

Weather Wit of the day: Evening Rain – Drips that pass in the night

>>> Highest Temperature Wednesday, September 17, 2025 – 114 at Death Valley, CA
>>> Lowest Temperature Wednesday, September 17, 2025 – 21 at Peter Sinks, Utah

 

Hawaii’s Broad Brush Weather Overview: Locally breezy trades will carry limited showers to the windward and mountain areas into Thursday. An increase in showers is then expected Thursday night into the weekend, followed by a return to a drier and more stable trade wind pattern thereafter.

Hawaii’s Weather Details: An upper low positioned north of Kauai supports a 63 mph subtropical jet stream draped over the eastern end of the state, and associated southwest flow aloft is carrying high clouds over and south of the Big Island. As the low drifts westward during the next few days, so too will the axis of southwest flow aloft, resulting in patchy high clouds area-wide for the rest of the week.

The low otherwise remains inconsequential through the near term, as it resides above strongly stable mid-levels. At the surface, a stable trade wind weather pattern prevails with a few modest patches of moisture poised to bring periodic showers to windward and mountain areas the next couple of nights.

Upstream, a cold front north presents as a narrow ribbon of enhanced moisture averaging about 5,000 feet in depth, except where deep convection exists along its convergent lead edge. Pockets of thunderstorms have been common along this boundary. As this moisture is ushered southwestward within prevailing trade winds, it will increasingly encounter a hostile mid-level environment that will tend to erode the deepest moisture, resulting in a trend toward decreasing deep convection as it approaches the islands. Low-level convergence itself will also tend to diminish with time given the dearth of mid-level support for the front.

Ongoing breezy trades will further limit prospects for meaningful low-level convergence, along which deep convection could organize. With that said, the resident upper low will provide very marginal support for isolated thunderstorms, within any pockets of deeper moisture, most likely over the western end of the state and at night. Low confidence at this point precludes inclusion of thunderstorms in the forecast over/around Oahu & Kauai.

Of note, guidance indicates a ENE to NE wind flow Friday night, which is favorable for directing moisture toward the Hamakua Coast of the Big Island, an area in need of rainfall. Guidance also indicates moisture arrival prior to full development of the mountain breeze, that would otherwise limit rainfall potential there.

A typical breezy trade wind pattern then prevails into next week.

Fire weather:  Expect decreasing fire weather risk as humidity gradually increases through the week into the weekend. Rain chances will increase Thursday night into the weekend, as deep pockets of moisture filter in on the trades, helping to potentially further alleviate fire weather concerns. Sustained winds briefly hover near to below the critical fire weather threshold each afternoon through Thursday, then trend slightly lighter for the weekend.

Here’s a near real-time Wind Profile of the Pacific Ocean – along with a Closer View of the islands / Vog map animation / 8-Day Precipitation model

https://www.weather.gov/images/hfo/graphics/npac.gif 

 

Hawaii’s Marine Environment:  Surface high pressure will remain anchored north of the state for the next several days, bringing moderate to locally strong trade winds across the local waters. However, winds are set to decrease slightly by Friday, as a front drops south and weakens the high. The latest pass depicts winds meeting Small Craft Advisory thresholds over portions of the western waters.

To account for this, Small Craft Advisories have been issued for the Kauai Channel and Kauai leeward waters in addition to the typically windy areas around Maui County and the Big Island. These advisories will likely be scaled back to the just the typical windy areas Thursday onward.

Surf along south facing shores will be tiny to small over the next few days, with mainly background south and southeast energy. A small to moderate, long-period, south-southwest swell will build Saturday into Sunday, helping to boost south shore surf heights back up to near or above the September average.

Surf along north facing shores should see a small increase into Thursday, as a short period northerly swell fills in. This small rise is expected to peak on Friday out of the north to north-northeast direction, followed by a short period north-northwest swell by the weekend. Moderate to locally strong trades near and upstream of the area will lead to slightly elevated and choppy conditions along east facing shores through this weekend.

 



World-wide Tropical Cyclone Activity

 

Atlantic Ocean: 

Tropical Cyclone 07 (Gabrielle)…is located about 895 miles east of the northern Leeward Islands

POORLY ORGANIZED GABRIELLE BATTLING STRONG WIND SHEAR AS IT JOGS TOWARD THE WEST-NORTHWEST

According to the NHC advisory number 4

Gabrielle is moving toward the west-northwest near 16 mph. A motion between west-northwest and northwest is expected for the next few days. Recent satellite data indicate that maximum sustained winds remain near 50 mph with higher gusts. Little change in strength is forecast during the next 48 hours, but some gradual intensification is forecast over the weekend. Tropical-storm-force winds extend outward up to 240 miles from the center, mostly to the north and northeast of the center. The estimated minimum central pressure is 1004 mb (29.65 inches).

cone graphic

 

East-Central Tropical Atlantic:

>>> A tropical wave located just west of the Cabo Verde Islands continues to produce disorganized shower activity. Development of this system is not expected while it moves westward across the eastern and central tropical Atlantic during the next several days.

* Formation chance through 48 hours…low…near 0 percent
* Formation chance through 7 days…low…near 0 percent

 

Eastern Tropical Atlantic:

>>> A tropical wave is forecast to move off the west coast of Africa by Friday morning. Some slow development of this system is possible over the weekend through the middle of next week while it moves west-northwestward across the eastern and central tropical Atlantic.

* Formation chance through 48 hours…low…near 0 percent
* Formation chance through 7 days…low…20 percent

 

Caribbean Sea:  There are no active tropical cyclone

Tropical cyclone formation is not expected during the next 7-days.

Gulf of America:  There are no active tropical cyclones

Tropical cyclone formation is not expected during the next 7-days.

 

Northeastern Pacific:  

Off the coast of Southwestern Mexico:

Invest 96E

>>> A broad area of low pressure located a few hundred miles off the coast of southwestern Mexico is producing a large area of showers and thunderstorms. Satellite-derived wind data indicate that the circulation remains fairly well organized. Environmental conditions are conducive for further development of this system, and a tropical depression is likely to form in the next day or two while it moves west-northwestward at 10 to 15 mph over the central portion of the eastern Pacific. However, the system is expected to encounter cooler waters and a drier airmass over the weekend, which will inhibit additional development.

* Formation chance through 48 hours…high…80 percent
* Formation chance through 7 days…high…80 percent

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

 

North Central Pacific: There are no active tropical cyclone

Tropical cyclone formation is not expected during the next 7 days.

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

 

Northwest Pacific Ocean: 

Tropical Cyclone 23W…is located approximately 303 NM east-southeast of Hong Kong

https://www.metoc.navy.mil/jtwc/products/wp2325.gif

Southwest Pacific Ocean:  There are no active tropical cyclones

North and South Indian Ocean:  There are no active tropical cyclones

South Indian Ocean: There are no active tropical cyclones

Arabian Sea:  There are no active tropical cyclones

Here’s a link to the Joint Typhoon Warning Center (JTWC)

 

>>> Here’s a link to the Pacific Disaster Center’s (PDC Global) Weather Wall website

 

Interesting:  Up, Up and Away: Dandelions Use Upward Winds to Spread Seeds

Chris Roh ’12 became interested in dandelions on walks with his toddler, picking the fluffy white spheres and blowing off their seeds. An aerospace engineer by training, Roh wondered about the fluid dynamics of this everyday activity. Why did some seeds release before others? And why did some seem to require much greater force to release?

New research by Roh, assistant professor of biological and environmental engineering in the College of Agriculture and Life Sciences, and his colleagues has uncovered the basic structural mechanics of how dandelions release and retain their seeds, opening new research pathways to understand plant evolution and seed dispersal in other wind-dispersed plants, such as lettuce and cotton.

In a new paper published Sept. 10 in the Journal of the Royal Society Interface, Roh and his co-authors report that dandelions respond to wind direction when releasing their seeds and have structures that make it harder for their seeds to release in unfavorable conditions. The first author of the paper is Jena Shields, a Ph.D. candidate in Roh’s lab.

Read More: Cornell University