Hawaiian Islands Weather Details & Aloha Paragraphs / May 11-12, 2018

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

81 – 69  Lihue, Kauai
84 – 71  Honolulu, Oahu
85 – 71  Molokai AP
86 – 69  Kahului AP, Maui
84 – 72  Kailua Kona
84 – 67  Hilo AP, Hawaii

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

0.37  Princeville AP, Kauai
0.92  Ahuimanu Loop, Oahu
0.30  Molokai
0.15  Lanai
0.03  Kahoolawe
0.37  Haiku, Maui
0.59  Honaunau, Big Island

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

14  Mana, Kauai
14  Bellows, Oahu
22  Molokai
28  Lanai
30  Kahoolawe
27  Kahului AP, Maui
29  Puu Mali, 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 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

Large high to the northeast…with a cold front northwest

High clouds moving over parts of the state

Partly to mostly cloudy skies…locally clear skies

Showers locally…mostly over the mountains
Looping image

 

~~~ Hawaii Weather Narrative ~~~

 

Small Craft Advisory…Maalaea Bay, Pailolo and Alenuihaha Channels, Big Island leeward and southeast waters

 

Broad Brush Overview: We find a mild-mannered surface trough of low pressure near the islands, along with a late season cold front passing by well to the north…which will keep light winds over the state for the time being. Clouds will increase over the islands, especially the upcountry areas, as onshore sea breezes blow thanks to the daytime heating of the islands. High pressure will pass by north of the islands this weekend, with trade wind weather and locally stronger winds returning. A surface ridge of high pressure will remain north of the islands next week, maintaining trade winds over our lovely islands.

Details: A weak surface trough near the islands, and a frontal cloud band passing by slowly to the north, will continue the generally light breezes across the state. Look for mostly fair weather for much of the islands with only a few showers, although a few could become a bit more generous here and there. The islands will become cloudier as the islands heat up under the sun’s influence, and begin to draw in those pleasant onshore flowing sea breezes. This in turn will trigger clouds forming over the slopes of the mountains, leading to afternoon and evening showers over the interior and leeward areas.

Looking Ahead: This surface trough will dissipate tonight through Saturday, as a new high passes slowly to the far north of the state over the weekend. There are differences in the models, in reference to how much moisture will remain over the islands this weekend, though with the moderate trade winds blowing any embedded showers will move quickly across the windward sides in general. The passing surface high is still expected to lift far northeast of the area Tuesday, though the trades will continue…as surface ridging will remain north of the islands. In sum, it looks as if we’ll find a fairly typical late spring trade wind weather pattern in place next week.

Here’s a wind profile of the Pacific Ocean – Closer view of the islands / Here’s the vog forecast animation / Here’s the latest weather map

Marine environment details: A weak surface trough will shift westward across the islands, keeping a light to moderate east to east-southeast wind flow in place across the local waters. The surface trough will shift west of the state tonight and Saturday, while high pressure builds northwest of the area, resulting in strengthening trade winds. The high will continue to shift eastward, well to the north of the islands through the remainder of the weekend into the first half of next week…with moderate to strong trade winds returning. Small Craft Advisory conditions will likely develop over the typically windy waters around Maui County and the Big Island sometime Saturday, and continue through early next week.

Lingering north-northwest swells will remain active through the weekend, although with surf heights below advisory levels. Surf along east facing shores will drop-off tonight as the trades weaken, and then increase again during the weekend with the strengthening trade winds. The south facing shores will see small surf through the weekend, with an increase expected early next week as a small swell moves it into the local waters.

 

World-wide Tropical Cyclone activity

Here’s the latest Pacific Disaster Center (PDC) Weather Wall Presentation…covering a tropical cyclone being referred to as Tropical Depression 01E in the eastern Pacific Ocean, and Tropical Depression 04W in the western Pacific

>>> Atlantic Ocean:

>>> Caribbean Sea:

>>> Gulf of Mexico:

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:

Tropical Cyclone 01E – Last Advisory

NHC textual advisory
NHC graphical track map
NOAA satellite image

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:

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

>>> Northwest Pacific Ocean: 

Tropical Cyclone 04W

JTWC textual Warning
JTWC graphical track map
NOAA satellite image

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

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


Interesting:  Kilauea Volcano Could Launch 10-Ton Ballistic Boulders in a Dramatic Explosion – Rockfalls and trapped lava could launch 10-ton “ballistic rocks” at Hawaii’s fiery Kilauea volcano, officials at the Hawaiian Volcano Observatory said May 9.

That’s because a lava lake near the summit of Kilauea is draining, setting the stage for a steam explosion.

The volcano has been undergoing big changes over the past few weeks, culminating in a dramatic eruption following a 5.0-magnitude earthquake and a subsequent magnitude-6.9 earthquake last week. That powerful outburst occurred after rockfalls caused the collapse of the Pu’u ‘O’o crater at the summit of Kilauea, which had been puffed up like a soufflé filled with red-hot lava. That lava had to go somewhere, and it oozed underground to the east rift zone of the mighty volcano, where magma doesn’t usually travel. New volcanic fissures or cracks opened up in the ground, allowing lava and toxic gases to escape into the surrounding residential areas, called Leilani Estates and Lanipuna Gardens.

A side effect of all these shifts is that a lava lake on the summit called Halema’uma’u has been draining like a bathtub; as of May 6, it had dropped 722 feet, according to the U.S. Geological Survey. As it continues to descend, the magma column could drop below the water table, the point where the ground is saturated with water, and heat up the groundwater.

And that could spell danger for the surrounding areas. With the lava in Halema’uma’u, the walls surrounding the dwindling lake are now steep and unstable, and rockfalls are inevitable, said Don Swanson, a geologist with the Hawaiian Volcano Observatory, said at a news conference yesterday.

“When you remove that support from the conduit and the crater, it causes instability and causes material to fall in,” Matt Patrick, a geologist with Hawaiian Volcano Observatory, said at the news conference.

In turn, there will be an increased risk that falling rocks will plug the conduit for Halema’uma’u; as lava heats the underground pool of water, steam will form but will have nowhere to go.

As pressure builds, eventually Kilauea will explode steam, hurling any loose rocks with it — a phenomenon known as a phreatic explosion, Tina Neal, a geologist with the Hawaiian Volcano Observatory, said at the news conference.

The volcano could eject rocks weighing as much as 10 to 12 tons over a distance of half a mile and launch pebble-size rocks across a couple of miles, according to geologists from the observatory.

This explosion could also eject dangerous amounts of ash, sulfur dioxide and acid rain. The clock begins to tick when the magma drops below the water table, which is likely to happen in mid-May, Swanson said.

Kilauea has been erupting continuously for decades, but it hasn’t spewed rocks in such an explosive manner since 1924, according to the Associated Press.

While the surrounding areas will be affected, the whole island is unlikely to see dramatic effects, Swanson said.

“Past explosive eruptions at Kilauea have been comparatively small on a worldwide scale,” Swanson said. “We don’t anticipate there being any wholesale devastation or evacuation.”

Meanwhile, the lava in the east rift zone is inching dangerously close to the Puna Geothermal Venture plant that houses 50,000 gallons of pentane, a volatile gas. But all of the pentane is expected to be removed now, the Associated Press reported.