Air Temperatures – The following maximum temperatures (F) were recorded across the state of Hawaii Tuesday…along with the minimums Tuesday:

78 – 69  Lihue, Kauai
84 – 68  Honolulu, Oahu
81 – 69  Molokai AP
83 – 70  Kahului AP, Maui
84 – 73  Kailua Kona
74 – 67  Hilo AP, Hawaii

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

0.83  Kilohana, Kauai
0.26  Waihee Pump, Oahu
0.09  Molokai
0.00  Lanai
0.00  Kahoolawe
0.92  West Wailuaiki, Maui
2.05  Honaunau, Big Island

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

23  Poipu, Kauai – NE
30  Kuaokala, Oahu – NNE
27   Molokai – N
29  Lanai – NE
27  Kahoolawe – NE
30  Kapalua, Maui – NNE
27  Upolu AP, Big Island – NE

Hawaii’s Mountains – Here’s a link to the live web cam on the summit of near 13,800 foot Mauna Kea on the Big Island of Hawaii. This web cam is available during the daylight hours here in the islands…and when there’s a big moon shining down during the night at times. Plus, during the nights you will be able to see stars, and the sunrise and sunset too…depending upon weather conditions.


Aloha Paragraphs

http://weather.unisys.com/satellite/sat_ir_enh_west_loop-12.gif
Low pressure systems over the ocean far to the northwest
through northeast…along with their trailing cold fronts

http://www.ssd.noaa.gov/goes/west/cpac/ir4.jpg
Clear to partly cloudy, cloudy areas…high cirrus clouds
southeast through southwest and north, and lots of
thunderstorms in the deeper tropics

 

http://www.ssd.noaa.gov/goes/west/hi/ir4.jpg
Remnant moisture from a dissipating frontal cloud band over
the Big Island…stretching back over windward Maui County

 

http://radar.weather.gov/Conus/RadarImg/hawaii.gif
Scattered showers…mostly windward areas
Looping radar image – (Kauai radar not working)

Small Craft Advisory…most coasts and channels
from Kauai down through Maui County, and
across the Alenuihaha Channel

High Surf Advisory…north and west shores of Kauai,
and north facing shores of Oahu, Molokai and Maui

 

~~~ Hawaii Weather Narrative ~~~



Trades winds continuing…a tad lighter by the weekend. Here’s the latest weather map, showing the Hawaiian Islands, and the rest of the North Pacific Ocean. We find high pressure systems offshore to the northwest through east of the islands. At the same time, we see a gale low pressure system northeast, along with the tail-end of its associated cold front offshore well to the east of the Big Island. Moderately strong trade winds will continue through the work week, with minor fluctuations in strength along the way. A cold front moving by to the north of the state during the weekend, will cause our trade wind flow to weaken a touch temporarily. The expectation is that moderately strong trade winds will return next week.

Here’s a wind profile…of the offshore waters around the islands – with a closer view

Here’s the Hawaiian Islands Sulfate Aerosol animated graphic – showing vog forecast

Typical spring time trade wind weather pattern. The trade winds will keep most showers focused along the windward sides. There’s still a bit of remnant moisture anchored over the windward sides of the eastern islands, although it’s not a big deal. A drier trade wind weather pattern will move into place beginning statewide Wednesday, with most showers arriving during the night and early morning hours through Friday. As a cold front moves by to the north of the islands during the weekend, we’ll likely see some increase in localized showers then. Otherwise, nothing out of the ordinary expected, with pleasant April weather conditions well into the future.

Marine environment details: An anticipated long-period west-northwest swell has been passing under buoy 51101 norethwest of Kauai through the day, with swell heights ranging between 6 and 7 feet. This swell will build in island waters tonight before peaking on Wednesday, with peak surf heights near advisory levels along exposed north and west facing shores. Surf will increase overnight, but at this time swell heights do not appear large enough to warrant a high surf advisory. The swell will then gradually diminish into the weekend. In addition, a small small swell is possible Friday and Saturday.

A small craft advisory /SCA/ is now in effect for the Alenuihaha channel, where terrain effects are most strongly felt, and where winds are near 25 knots. With a slight uptick in wind speeds possible tomorrow and Thursday, it’s possible that the SCA may need to be expanded again to include other zones around Maui County and the Big Island.

 

    http://www.fodors.com/ee/files/slideshows/4-Explore-Kauais-Napali-Coast-2.jpg
Rising surf along north and west shores…trade winds


Here on Maui – Well before sunrise on this Tuesday morning, we find partly to mostly cloudy skies along the windward coasts and slopes…stretching up over the West Maui Mountains. These clouds are dropping a few showers, although nothing heavy or too overbearing. Elsewhere around the island, skies were clear, setting the stage for a nice day coming up. Here in upcountry Kula, it’s clear and calm, with an air temperature at my weather tower of 50F degrees. At near the same time, the Kahului AP was registering 70 degrees with cloudy skies, while it was 68 out in Hana, and 43 atop the Haleakala Crater.

– Late afternoon, under sunny to partly cloudy skies in general, although as usual…there are a few cloudy areas as well. The windward sides in particular, have had quite a few clouds the last 24+ hours, along with showers at times too.

– Early evening, a good mix of clear blue skies, and partly to mostly cloudy conditions in places too. Was today a spring day? In my humble opinion, it could have easily passed as a mid-summer day! The rather persistent cloudiness and off and on showers along our windward sides, should fade away as we get into Wednesday. The leeward sides will continue to have great weather!

 

~~~ I recently got a question from a fellow employee of the Pacific Disaster Center, asking me about the upcoming 2016 hurricane season in the Central Pacific. I wrote a few words in response, and thought I’d share them with you:

As for the upcoming 2016 hurricane season in the Central Pacific, quite honestly I’d prefer not to get out ahead of what the NWS Central Pacific Hurricane Center will be announcing a little later this spring.

With that said, I notice that NOAA is saying: “A transition to ENSO-neutral is likely during late Northern Hemisphere spring or early summer 2016, with an increasing chance of La Niña during the second half of the year.”

This is good news, in contrast to the strong El Nino that we pushed through during the 2015 hurricane season.

In simple terms, El Nino-neutral heading towards La Nina conditions, will present tropical cyclones with less favorable environmental conditions…especially in terms of cooler sea surface temperatures.

So, in general terms, I would expect a less active hurricane season this summer (compared to last year) into the fall season as well.

As you may remember, on January 7th, 2016 Hurricane Pali formed here in the Central Pacific, becoming the earliest Central Pacific tropical cyclone to form on record. Therefore, we’ve already had one tropical cyclone this year, although it was very much a part of the very strong El Nino of last year…into the first part of this year.

As you know, the hurricane season will officially start on May 15th in the East Pacific Ocean, and on June 1st here in the Central Pacific…they will both end on November 30th.

These dates conventionally delimit the period of each year when most tropical cyclones form in the Pacific basin. However, as illustrated by Hurricane Pali…the formation of tropical cyclones is possible at any time of the year…especially when we have strong El Nino conditions present.

By the way, this marked the earliest formation of a tropical cyclone on record in the Central Pacific, surpassing 1989’s Tropical Storm Winona by six days.

 

World-wide tropical cyclone activity:

>>> Atlantic Ocean: The last regularly scheduled Tropical Weather Outlook of the 2015 Atlantic hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant. Here’s the 2015 hurricane season summary

Here’s a satellite image of the Atlantic Ocean

>>> Caribbean Sea: The last regularly scheduled Tropical Weather Outlook of the 2015 Atlantic hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant.

>>> Gulf of Mexico: The last regularly scheduled Tropical Weather Outlook of the 2015 Atlantic hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant.

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: The last regularly scheduled Tropical Weather Outlook of the 2015 North Pacific hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on May 15, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant. Here’s the 2015 hurricane season summary

Here’s a wide satellite image that covers the entire area between Mexico, out through the central Pacific…to the International Dateline.

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

>>> Central Pacific: The central north Pacific hurricane season has officially ended. Routine issuance of the tropical weather outlook will resume on June 1, 2016. During the off-season, special tropical weather outlooks will be issued if conditions warrant. Here’s the 2015 hurricane season summary

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

>>> Northwest Pacific Ocean: No active tropical cyclones

>>> South Pacific Ocean: 

Tropical Cyclone 20P is now active near Fiji and American Samoa, in the South Pacific Ocean…here’s the JTWC graphical track map, a satellite image, and what the computer forecast models are showing


>>> North and South Indian Oceans / Arabian Sea:

Tropical Cyclone 19S (Fantala) remains active near Madagascar in the South Indian Ocean…here’s the JTWC graphical track map, a satellite image, and what the computer forecast models are showing

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


Interesting: MIT finds tectonic collisions had major impact on climatic shifts – For hundreds of millions of years, Earth’s climate has remained on a fairly even keel, with some dramatic exceptions: Around 80 million years ago, the planet’s temperature plummeted, along with carbon dioxide levels in the atmosphere. The Earth eventually recovered, only to swing back into the present-day ice age 50 million years ago. 

Now geologists at MIT have identified the likely cause of both ice ages, as well as a natural mechanism for carbon sequestration. Just prior to both periods, massive tectonic collisions took place near the Earth’s equator — a tropical zone where rocks undergo heavy weathering due to frequent rain and other environmental conditions. This weathering involves chemical reactions that absorb a large amount of carbon dioxide from the atmosphere. The dramatic drawdown of carbon dioxide cooled the atmosphere, the new study suggests, and set the planet up for two ice ages, 80 million and 50 million years ago. 

“Everybody agrees that on geological timescales over hundreds of millions of years, tectonics control the climate, but we didn’t know how to connect this,” says Oliver Jagoutz, associate professor of Earth, Atmospheric and Planetary Sciences (EAPS) at MIT. “I think we’re the first ones to really link large-scale tectonic events to climate change.”

Jagoutz and his colleagues, EAPS Professor Leigh Royden, and Francis McDonald of Harvard University, have published their findings in the Proceedings of the National Academy of Sciences. 

Putting the squeeze on

The two tectonic collisions that the team studied stemmed from the same event: the slow northward migration of Gondwana, a supercontinent that spanned the Southern Hemisphere from 300 million to 180 million years ago and eventually broke up to form Antarctica, South America, Africa, India, and Australia. 

Around 180 million years ago, tectonic activity began to push fragments of Gondwana up toward the northern supercontinent of Eurasia, which slowly squeezed and eventually closed the Neo-Tethys Ocean, an ancient body of water lying between the supercontinents.

In previous work, Jagoutz and his colleagues developed a model to simulate the tectonic shifting that occurred in and around that ocean as Gondwana fragments were crushed against Eurasia. Through analysis of ancient rocks in today’s Himalayas, the team determined a sequence of events as the continents merged.

They found that 90 million years ago, the northeastern edge of the African plate collided and slid under an oceanic plate in the Neo-Tethys Ocean, creating a chain of volcanoes. At 80 million years ago, as Africa continued advancing north, the oceanic plate was pushed further up and over the continent, exposing ocean rock to the atmosphere, while simultaneously terminating the volcanoes. Then, 50 million years ago, India merged with Eurasia in a second collision in which a different region of the oceanic plate was pushed up onto that continent.

Both collisions took place in the Intertropical Convergence Zone (ITCZ), an atmospheric region hovering over the Earth’s equator, in which trade winds come together to generate a region of intense temperatures and rainfall.

A weathering trigger

For this new paper, the researchers wondered whether the tectonic collisions in this extremely tropical region may have played a part in pulling huge amounts of carbon dioxide out of the atmosphere and triggering the ice ages.

Certain types of rock, if exposed to high heat and heavy rain, undergo chemical reactions and effectively absorb carbon dioxide, a process known as silicate weathering. These rocks include basalts and “ultramafic” rocks, which are often found within oceanic plates. If these rocks are exposed to the atmosphere in a tropical region, they can act as very efficient carbon sinks.

The team hypothesized that the two collisions, involving Africa and then India, brought basaltic and ultramafic rocks up from the oceans and onto land, creating carbon sinks 80 and 50 million years ago. Both collisions also effectively turned off carbon sources by burying volcanoes that had been emitting carbon dioxide and other gases into the atmosphere.

To know whether such a sequence of events directly reduced carbon dioxide in the atmosphere, the researchers looked to weathering rates of different rock types, including granites, basalts, and ultramafics. These rates, which have been calculated by other researchers, describe the way rocks erode and take up carbon dioxide, given exposure to a certain amount of rainfall.

They then applied these weathering rates to their model’s estimates of the amount of oceanic plate that was pushed up onto Africa and India, at 80 and 50 million years ago, respectively. After determining the amount of carbon dioxide sequestered by these rocks, they calculated the total amount of atmospheric carbon dioxide through time, from 100 million years ago to around 40 million years ago.

The team found that carbon dioxide dipped dramatically at precisely the time the two collisions occurred. The levels of carbon dioxide also mirrored the temperature of the oceans during this interval.

Jagoutz says one reason these two collisions had such an extreme effect on atmospheric carbon dioxide may have been the fact that each continent continued moving north, exposing new basaltic and ultramafic material, “like a bulldozer that brings fresh rock to the surface.”

Interestingly, a similar process is taking place today, albeit at a smaller scale, near the island of Java. The same tectonic activity that shifted Gondwana northward more than 100 million years ago is today pushing the Australian plate north, and as a result, is piling up basaltic material on Java within the ITCZ, which Jagoutz says is “a huge carbon sink.”

“What nature shows us is, if you put a lot of these rocks in the tropics, where it’s hot, muggy, wet, and rains every day, and you also have the effect of removing the soil constantly by tectonics and thus exposing fresh rocks, then you have an excellent trigger for ice ages,” Jagoutz says. “But the question is whether that is a mechanism that works on the timescale that is relevant for us.”