Air Temperatures – The following high temperatures (F) were recorded across the state of Hawaii Sunday…along with the low temperatures Sunday:

82 – 73  Lihue, Kauai
83 – 73  Honolulu, Oahu
88 – 73  Molokai AP
89 – 72  Kahului AP, Maui
85 – 73  Kailua Kona
85 – 68  Hawaii

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

3.37  Kilohana, Kauai
1.73   Poamoho, Oahu
0.52  Molokai
0.08  Lanai
 0.00  Kahoolawe
0.08  Haiku, Maui
0.30  Honaunau, Big Island

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

13  Poipu, Kauai
21  Oahu Forest NWR, Oahu
18  Molokai
08  Lanai
12  Kahoolawe
21  Kula 1, Maui
21  Kealakomo, Big Island

Hawaii’s Mountains – Here’s a link to the live webcam on the summit of our tallest mountain Mauna Kea (nearly 13,800 feet high) on the Big Island of Hawaii. Here’s the webcam for the 10,000+ 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.


Aloha Paragraphs


http://www.ssd.noaa.gov/goes/west/tpac/avn-animated.gif
 Hurricane Norman on the current forecast track will come towards Hawaii, likely passing northeast of the islands…as a weakening tropical storm / it won’t be long before Tropical Storm Olivia will become a hurricane, likely passing northeast of the islands (as well)…as a weakening storm  (click images to enlarge)

http://www.goes.noaa.gov/GIFS/HPIR.JPG

 Hurricane Norman and Tropical Storm Olivia in the eastern Pacific

https://www.nhc.noaa.gov/storm_graphics/EP16/refresh/EP162018_5day_cone_with_line_and_wind+png/123152_5day_cone_with_line_and_wind.png

https://www.nhc.noaa.gov/storm_graphics/EP17/refresh/EP172018_5day_cone_with_line_and_wind+png/023536_5day_cone_with_line_and_wind.png

http://www.ssd.noaa.gov/goes/west/cpac/ir4.jpg
 Hurricane Norman is moving into the picture…well to the east


http://www.ssd.noaa.gov/goes/west/hi/ir4.jpg
Clear to partly cloudy…cloudy areas locally

 

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Low clouds arriving on the trade winds

 

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Showers locally and offshore
 Looping image

 

~~~ Hawaii Weather Narrative ~~~

 

Broad Brush Overview: A trough of low pressure moving through the island chain, will continue to bring clouds and showers to the smaller islands into Monday morning. A more typical trade wind pattern of windward showers will become established over the Big Island tonight and tomorrow. Meanwhile lighter winds over the smaller islands will lead to afternoon clouds and showers. A return to a more typical trade wind pattern is expected Tuesday and Wednesday across the state.

Details: Lighter winds will develop across the state, spreading westward to Kauai and Oahu tonight, as the trough slowly passes through the state. These lighter winds will allow onshore sea breezes to develop on Labor Day Monday, with converging clouds and scattered afternoon interior showers over each island. Offshore land breezes will clear out cloud cover and diminish showers in the overnight hours. Wind speeds will increase on Tuesday, as trade winds return behind the trough…with more typical windward and mountain showers.

Looking Ahead: Another dry and stable area reaches the island Wednesday into Thursday morning, with mostly sunny skies and low chances for showers in the forecast…thanks to Hurricane Norman approaching the islands from the east. This will occur as sinking (subsident) air typically produces a dry and stable layer of air ahead of the Hurricane. As we push into Thursday afternoon onward the forecast weather conditions remain a bit less certain, as much will be based on the final track and approach of Hurricane Norman.

The models continue to keep the track of the Hurricane passing northeast of the Hawaiian Islands during this period. The track of Norman may block the trade winds keeping a light overnight land and afternoon sea breeze regime in place over each island. Scattered showers are possible each afternoon, mainly over mountain and upcountry interior sections. Hurricane Norman, remains far east of the state, and will continue to move closer to the islands through the middle of the week. It remains too soon to determine any local impact that Norman may have on Hawaiian weather.

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 / Here’s the latest Vog Forecast Animation / Here’s the Vog Information website

Marine Environmental Conditions: Trades will be trending down into the light to moderate range, as high pressure shifts eastward over the northeast Pacific and Miriam tracks far northeast of the area. Moderate to strong trades are forecast to return Tuesday through mid-week, although things become more uncertain beyond that…as Hurricane Norman approaches.

Surf along east facing shores will remain elevated due to a combination of fading wind waves and swell from Miriam. This swell will become reinforced early in the new week as Hurricane Norman approaches from the east. If Norman continues westward at a higher latitude, the Big Island should not have as much of a shadowing impact on the smaller islands. As a result, surf could exceed advisory thresholds for all east facing shores, and potentially reach warning levels, around mid-week. With an energy bump from the south-southwest, surf may rise modestly along south facing shores, below advisory levels…then fade as we get into the new week.



World-wide Tropical Cyclone Activity

 

Here’s the latest Pacific Disaster Center (PDC) Weather Wall Presentation covering Tropical Storm 06L (Florence), and Tropical Storm 07L (Gordon) in the Atlantic Ocean

Here’s the latest Pacific Disaster Center (PDC) Weather Wall Presentation covering the Pacific and Indian Oceans, including Post-tropical cyclone 15E (Miriam), Hurricane 16E (Norman), Tropical Storm 17E Olivia, and Typhoon 25W (Jebi)


>>> Atlantic Ocean:

Tropical Storm 06L (Florence) remains active…and will remain a tropical storm over the open ocean

According to the NHC…Florence is moving toward the west-northwest near 16 mph. The tropical storm is expected to move generally westward to west-northwestward at a slightly slower forward speed for the next several days. Maximum sustained winds are near 60 mph with higher gusts. Little change in intensity is expected over the next several days. Tropical-storm-force winds extend outward up to 60 miles from the center.

Here’s what the computer models are showing

1.) A tropical wave located more than 400 miles southeast of the Cabo Verde Islands is producing a large area of disorganized showers and thunderstorms. Some slow development of this disturbance is possible during the next several days while the system moves westward to west-northwestward across the eastern tropical Atlantic.

* Formation chance through 48 hours…low…near 0 percent
* Formation chance through 5 days…low…30 percent

>>> Caribbean Sea: 

>>> Gulf of Mexico: 

Tropical Storm 07L (Gordon)…will be active over portions of the central Gulf Coast Tuesday night and Wednesday

According to the NHC…Gordon is moving toward the west-northwest near 17 mph and a west- northwestward to northwestward motion is expected over the next 72 hours. On the forecast track, the center of Gordon will pass over the southern tip of the Florida peninsula this morning, move over the southeastern Gulf of Mexico this afternoon and evening, and reach the warning area along the central Gulf Coast by late Tuesday or Tuesday night. Surface observations and radar data indicate that maximum sustained winds have increased to near 45 mph with higher gusts. Additional strengthening is forecast during the next 48 hours. Tropical-storm-force winds extend outward up to 45 miles from the center.

Here’s what the computer models are showing

Here’s a satellite image of the Caribbean Sea…and the Gulf of Mexico

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

>>> Eastern Pacific:

Hurricane 16E (Norman) remains active…as a Category 3 storm

Here’s what the computer models are showing


According to the NHC…Norman is moving toward the west-northwest near 20 mph. This general motion with a gradual decrease in forward speed is expected through mid-week. Maximum sustained winds are near 125 mph with higher gusts. Steady weakening is expected during the next several days. Hurricane-force winds extend outward up to 35 miles from the center and tropical-storm-force winds extend outward up to 115 miles.

Tropical Storm 17E (Olivia) remains active…and will strengthen as it heads west-northwest

Here’s what the computer models are showing

According to the NHC…Olivia is moving toward the west near 7 mph, and this general motion is expected to continue through Tuesday. A turn toward the west-northwest with an increase in forward speed is expected on Wednesday. Maximum sustained winds are near 45 mph with higher gusts. Gradual strengthening is forecast through Tuesday. Thereafter, little change in strength is expected through Thursday. Tropical-storm-force winds extend outward up to 140 miles from the center.

 

1.) A broad area of low pressure could form well south of the southwestern coast of Mexico in a few days. Development of this system, if any, should be slow to occur while it moves west-northwestward later this week.

* Formation chance through 48 hours…low…near 0 percent
* Formation chance through 5 days…low…10 percent

>>> Central Pacific: No active tropical cyclones

>>> Northwest Pacific Ocean:

Typhoon 25W (Jebi)

JTWC textual advisory
JTWC graphical track map

>>> South Pacific Ocean: No active tropical cyclones

>>> North and South Indian Oceans / Arabian Sea: No active tropical cyclones

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

 

Interesting: A new way to remove ice buildup without power or chemicals – From airplane wings to overhead powerlines to the giant blades of wind turbines, a buildup of ice can cause problems ranging from impaired performance all the way to catastrophic failure. But preventing that buildup usually requires energy-intensive heating systems or chemical sprays that are environmentally harmful. Now, MIT researchers have developed a completely passive, solar-powered way of combating ice buildup.

The system is remarkably simple, based on a three-layered material that can be applied or even sprayed onto the surfaces to be treated. It collects solar radiation, converts it to heat, and spreads that heat around so that the melting is not just confined to the areas exposed directly to the sunlight. And, once applied, it requires no further action or power source. It can even do its de-icing work at night, using artificial lighting.

The new system is described today in the journal Science Advances, in a paper by MIT associate professor of mechanical engineering Kripa Varanasi and postdocs Susmita Dash and Jolet de Ruiter.

“Icing is a major problem for aircraft, for wind turbines, power lines, offshore oil platforms, and many other places,” Varanasi says. “The conventional ways of getting around it are de-icing sprays or by heating, but those have issues.”

Inspired by the sun

The usual de-icing sprays for aircraft and other applications use ethylene glycol, a chemical that is environmentally unfriendly. Airlines don’t like to use active heating, both for cost and safety reasons. Varanasi and other researchers have investigated the use of superhydrophobic surfaces to prevent icing passively, but those coatings can be impaired by frost formation, which tends to fill the microscopic textures that give the surface its ice-shedding properties.

As an alternate line of inquiry, Varanasi and his team considered the energy given off by the sun. They wanted to see, he says, whether “there is a way to capture that heat and use it in a passive approach.” They found that there was.

It’s not necessary to produce enough heat to melt the bulk of the ice that forms, the team found. All that’s needed is for the boundary layer, right where the ice meets the surface, to melt enough to create a thin layer of water, which will make the surface slippery enough so any ice will just slide right off. This is what the team has achieved with the three-layered material they’ve developed.

Layer by layer

The top layer is an absorber, which traps incoming sunlight and converts it to heat. The material the team used is highly efficient, absorbing 95 percent of the incident sunlight, and losing only 3 percent to re-radiation, Varanasi says.

In principle, that layer could in itself help to prevent frost formation, but with two limitations: It would only work in the areas directly in sunlight, and much of the heat would be lost back into the substrate material — the airplane wing or powerline, for example — and would not help with the de-icing.

So, to compensate for the localization, the team added a spreader layer — a very thin layer of aluminum, just 400 micrometers thick, which is heated by the absorber layer above it and very efficiently spreads that heat out laterally to cover the entire surface. The material was selected to have “thermal response that is fast enough so that the heating takes place faster than the freezing,” Varanasi says.

Finally, the bottom layer is simply foam insulation, to keep any of that heat from being wasted downward and keep it where it’s needed, at the surface.

“In addition to passive de-icing, the photothermal trap stays at an elevated temperature, thus preventing ice build-up altogether,” Dash says.

The three layers, all made of inexpensive commercially available material, are then bonded together, and can be bonded to the surface that needs to be protected. For some applications, the materials could instead be sprayed onto a surface, one layer at a time, the researchers say.

The team carried out extensive tests, including real-world outdoor testing of the materials and detailed laboratory measurements, to prove the effectiveness of the system.

“The use of photothermal absorbers is a smart idea and straightforward to implement,” says Manish Tiwari, a professor of nanoengineering at University College London, who was not associated with this research. “Scalability of these approaches and thinking about appropriate packaging, specific weight, etc., of the de-icing layer are important practical challenges going ahead, especially when it comes to the aerospace application. The paper also opens up intriguing possibilities around smart and flexible thermal packaging, and thermal metamaterials research to realize its full potential. Overall, an excellent step forward,” he says.

The system could find even wider commercial uses, such as panels to prevent icing on roofs of homes, schools, and other buildings, Varanasi adds. The team is planning to continue work on the system, testing it for longevity and for optimal methods of application. But the basic system could essentially be applied almost immediately for some uses, especially stationary applications, he says.