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

78 – 61  Lihue, Kauai
81 – 67  Honolulu, Oahu
82 – 61  Kahului AP, Maui
81 – 68  Kailua Kona
83 – 63  Hilo AP, Hawaii

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

0.96  Wailua, Kauai
1.77  Kahana, Oahu
 0.01  Molokai
 0.03  Lanai
 0.08  Kahoolawe
0.25  Maalaea Bay, Maui
1.95  Kahuku Ranch, Big Island

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

23  Port Allen, Kauai
24  Waianae Harbor, Oahu
13  Molokai
13  Lanai
16  Kahoolawe
18  Kula 1, Maui
27  Kaloko-Honokohau, 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

http://weather.unisys.com/satellite/sat_ir_enh_west_loop-12.gif
A trough is moving away…with the next cold front approaching to the northwest

http://www.ssd.noaa.gov/goes/west/cpac/ir4.jpg
The atmosphere is beginning to stabilize

http://www.ssd.noaa.gov/goes/west/hi/ir4.jpg
Deep clouds…with embedded thunderstorms now mostly to our east and north

https://radar.weather.gov/Conus/RadarImg/hawaii.gif
Showers locally…much less heavy now – Looping image

 

~~~ Hawaii Weather Narrative ~~~


High Wind Warning…Big Island summits / 30-50 with gusts to 75 mph

 

Broad Brush Overview: A long lasting trough of low pressure over the state is finally moving away, gradually taking the unstable conditions away. Drier stable weather will return Thursday through the end of the week, as the trough moves east and trade winds spread back across the islands behind a weak cold front. Uneventful trade wind weather should prevail during the weekend, although another episode of wet and unstable weather is possible early next week…as another strong trough deepens northwest of the islands.

Details:  The models show the trough finally pushing east of the state now into Thursday, with a ridge aloft building into the area from the west. A weak cold front will also reach Kauai Thursday morning, then dissipate as it moves down the island chain through Friday. These developments will bring drier and more stable conditions, with surface high pressure behind the front bringing increasingly strong trade winds to the islands. The trades should then continue through the weekend, with passing light showers over windward areas…and mainly dry conditions leeward.

Looking Further Ahead:  The models continue to develop a deep trough aloft somewhere over the Central North Pacific as we move into next week…although there are major differences in the exact timing and location of this next trough. We’ll need to wait patiently as the various models sort out these differences. However, it looks like the potential for another bout of wet and possibly stormy weather isn’t out of the question during the early to middle part of 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: Although large-scale winds are light due to a surface trough over the area, locally gusty winds associated with strong thunderstorms remain a concern for mariners, as well as the potential for waterspouts and lightning. With the slow-moving north to south oriented surface trough near Molokai, the most likely area for strong storms will primarily be over Maui and Big Island waters. However, thunderstorms could pop-up just about anywhere over the coastal waters, as a trough aloft remains over the islands. This trough will move from west to east across the area tonight through Thursday night, with the threat of thunderstorms diminishing as the associated instability exits the region.

Gentle north winds will prevail west of the surface trough, with light and variable winds east of the trough axis. Tonight and Thursday the trough will slide east, as high pressure builds northwest of the state. The building high will help to push a weak and shallow cold front down the island chain, supporting increasing north winds Thursday, and moderate to trade winds Friday and Saturday. A Small Craft Advisory will likely be needed for most areas behind the front Thursday and Friday, due to a combination of increased winds, and combined seas associated with a rising northwest swell. Winds may ease and veer to the east Sunday as the trough drifts back west over the islands.

The current northwest swell continues a slowly lower. The next northwest swell expected Thursday night, will bring advisory level surf to exposed north and west facing shores through Friday before declining steadily over the weekend. Another similar sized northwest swell is possible early next week.


https://www.thesun.co.uk/wp-content/uploads/2016/12/nintchdbpict000248194960.jpg?w=960
Gradually returning trade winds…with improving weather



World-wide Tropical Cyclone activity

>>> Here’s the latest PDC Weather Wall Presentation, covering Tropical Cyclone 07S (Cebile) in the South Indian Ocean, and a tropical disturbance being referred to as Invest 93W well southeast of Guam in the western Pacific Ocean…and finally a second tropical disturbance called Invest 97P


https://icons.wxug.com/data/images/sst_basin/gl_sst_mm.gif


>>> 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:

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: No active tropical cyclones

>>> South Pacific Ocean: No active tropical cyclones


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

Tropical Cyclone 07S (Cebile)

JTWC textual forecast warning
JTWC graphical track map
NOAA satellite image

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


Interesting: Volcano Facts and Types of Volcanoes – A volcano on Earth is a vent or fissure in the planet’s crust through which lava, ash, rock and gases erupt. A volcano is also a mountain formed by the accumulation of these eruptive products.

Volcanoes have existed for a long time on Earth, likely causing disasters such as the Permian mass extinction about 250 million years ago, the greatest mass extinction in Earth’s history, according to a 2015 paper. Volcanoes can and have existed on other worlds as well: although volcanoes on the moon and Mars have long been dormant, volcanoes are still very active on Jupiter’s moon Io. Researchers are currently striving to find ways to predict when volcanic eruptions might happen on Earth by analyzing clues such as crystals and gases linked with volcanoes.

Earth’s crust is 3 to 37 miles thick, according to the U.S. Geological Survey. It is broken up into seven major and 152 smaller pieces called tectonic plates, according to a 2016 paper by Christopher Harrison at the University of Miami. These plates float on a layer of magma — semi-liquid rock and dissolved gases. At the boundaries of these plates — where they move past, are pushed under, or move away from each other — magma, which is lighter than the surrounding solid rock, is often able to force its way up through cracks and fissures. Magma can explode from the vent, or it can flow out of the volcano like an overflowing cup. Magma that has erupted is called lava.

Principal types of volcanoes

Cinder cone volcanoes (also called scoria cones) are the most common type of volcano, according to San Diego State University, and are the symmetrical cone-shaped volcanoes we typically think of. They may occur as single volcanoes or as secondary volcanoes known as “parasitic cones” on the sides of stratovolcanoes or shield volcanoes. Airborne fragments of lava, called tephra, are ejected from a single vent. The lava cools rapidly and fall as cinders that build up around the vent, forming a crater at the summit, according to the U.S. Geological Survey. Cinder cone volcanoes are fairly small, generally only about 300 feet tall and not rising more than 1,200 feet. They can build up over short periods of a few months or years.

Stratovolcanoes are also called composite volcanoes because they are built of layers of alternating lava flow, ash and blocks of unmelted stone, according to the U.S. Geological Survey. They are larger than cinder cones, rising up to 8,000 feet. Stratovolcanoes result from a conduit system of vents leading from a magma reservoir beneath the surface. When dormant, they typically have steep concave sides that sweep together at the top around a relatively small crater.

Stratovolcanoes can erupt with great violence. Pressure builds in the magma chamber as gases, under immense heat and pressure, are dissolved in the liquid rock. When the magma reaches the conduits the pressure is released and the gases explode, like soda spewing out of a soda can that you shook up and opened suddenly, according to San Diego State University. Because they form in a system of underground conduits, stratovolcanoes may blow out the sides of the cone as well as the summit crater.

Stratovolcanoes are considered the most violent. Mount St. Helens, in Washington state, is a stratovolcano that erupted on May 18, 1980. Approximately 230 square miles of forest was completely obliterated and 57 people were killed. Over the course of the day, winds blew 520 million tons of ash eastward across the United States and caused complete darkness in Spokane, Washington, 250 miles from the volcano, according to the U.S. Geological Survey.

Shield volcanoes are huge, gently sloping volcanoes built of very thin lava spreading out in all directions from a central vent. They have wide bases several miles in diameter with steeper middle slopes and a flatter summit. The gentle convex slopes give them an outline like a medieval knight’s shield. Eruptions of these volcanoes are not generally explosive, but are more like liquid overflowing around the edges of a container. The world’s largest volcano, Mauna Loa in Hawaii, is a shield volcano, according to the U.S. Geological Survey. Mauna Loa is about 55,770 feet from its base beneath the ocean to the summit, which is 13,681 feet above sea level. It is also one of the Earth’s most active volcanoes and is carefully monitored. The most recent eruption was in 1984.

Lava domes are built up when the lava is too viscous to flow, according to the U.S. Geological Survey. A bubble or plug of cooling rock forms over a fissure. This cooler, thick lava usually rises near the end of an explosive eruption and lava domes often form within the craters of stratovolcanoes. Mount St. Helens has several well-defined lava domes inside the crater, according to NASA.

Other volcanic landforms

Besides well-known symmetrical volcanoes such as Mount Fuji in Japan and Kilimanjaro in Tanzania, volcanic activity is responsible for several other distinctive landforms.

Calderas: A caldera is a bowl-shaped depression formed when a volcano collapses into the void left when its magma chamber is emptied. There are three types, according to San Diego State University. The first type is a crater lake caldera. This is the result of a stratovolcano collapsing into its magma chamber during a violent eruption. Basaltic calderas have a concentric ring pattern resulting from a series of gradual collapses rather than a single event. They are often found at the summit of shield volcanoes such as the craters at the tops of Mauna Loa and Kilauea. Resurgent calderas are the largest volcanic structures on Earth. They are the result of catastrophic eruptions that dwarf any eruptions ever recorded by human beings. Yellowstone caldera, sometimes called a “super volcano,” is one example.

Volcanic plugs: When magma solidifies in the fissure of a volcano the hard dense rock may form a “neck” that remains when softer surrounding rock has been eroded away, according to the U.S. Geological Survey. This can result in dramatic landmarks such as Ship Rock in New Mexico, and Devil’s Tower in Wyoming.

Tuff cones: also known as maars, tuff cones are shallow, flat-floored craters that scientists think formed as a result of a violent expansion of magmatic gas or steam, according to the U.S. Geological Survey. Maars range in size from 200 to 6,500 feet across and from 30 to 650 feet deep, and most are commonly filled with water to form natural lakes. Maars occur geologically young volcanic regions of the world such as the western United States and the Eifel region of Germany.

Lava plateaus: Shield volcanoes may erupt along lines of fissures rather than a central vent spilling liquid lava in successive layers. Over time as these layers form broad plateaus such as the Columbia Plateau, according to the Encyclopedia Britannica. These plateaus are often cut by deep canyons that expose the layers of rock.

Volcanoes in history

A.D. 79: One of the most famous volcanoes is Mount Vesuvius, which sits along the Bay of Naples in southern Italy. It has erupted dozens of times in the past 2,000 years, according to the Encyclopedia Britannica. The A.D. 79 eruption, which buried Pompeii, made Vesuvius famous, but another eruption in 1631 killed about 3,000 people.

1669: In Sicily, Mount Etna sent a river of lava flooding through Catania, according to Geology.com, killing some 20,000 people there and in the surrounding region, according to NASA.

1783: The eruption of Mount Skaptar in Iceland devastated farming and fishing, causing a famine that killed a quarter of the country’s people, according to Oregon State University.

1815: Whirlwinds and tsunamis from the eruption of Mount Tambora, on Sumbawa Island in Indonesia, killed at least 10,000 people, according to the Encylopedia Britannica. The volcano sent a cloud ejecta into the atmosphere that was more than four times the amount ejected by Mount Pinatubo in 1991, leading to the “Year Without a Summer” of 1816 in Europe and North America, according to a 2016 paper in Wiley Interdisciplinary Reviews: Climate Change.

1883: Another Indonesian volcano, Krakatoa, erupted in an explosion heard 3,000 miles away. Seventy-pound boulders landed on islands 50 miles away, and a 130-foot tsunami devastated hundreds of villages, including Java and Sumatra, according to San Diego State University. About 36,000 people died. Dust high in the atmosphere caused the moon to appear blue, and sometimes green, for two years, according to NASA.

1902: Mount Pelée, on the island of Martinique, smothered the town of Saint-Pierre in deadly gas and hot ash, killing 29,933, according to the Los Angeles Times.

1980: Mount St. Helens in Washington state blew 1,300 feet off its top, killing 57 people and causing a midday darkness in towns 85 miles away.

1991: After 600 years of dormancy, Mount Pinatubo in the Philippines rumbled for days before erupting and killing more than 840 people, according to the U.S. Geological Survey. The cataclysmic ejected more than 1 cubic mile of material and buried a U.S. air base 15 miles away, according to the National Oceanic and Atmospheric Administration. Nearly every bridge within 18 miles (30 km) of Mount Pinatubo was destroyed, according to the U.S. Geological Survey.

Pinatubo’s cloud of sulfuric acid, some 20 million tons of it, climbed to more than 12 miles in the stratosphere. Over the next several weeks, the cloud encircled the equator and spread to the poles, covering the entire planet. The particles reflected sunlight and cooled the Earth by nearly a full degree Fahrenheit.

Other significant U.S. volcanoes

Lassen Peak, California: Erupted between 1914 and 1917, causing no deaths, according to the National Park Service. Lassen is considered one of the most likely in the Cascade Range to erupt again.

Long Valley, California: The Long Valley Caldera is a 10-by 20-mile (16-by-32 kilometer) depression in the Sierra Nevada Mountains caused by an eruption 700,000 years ago, according to the U.S. Geological Survey. A tremendous explosion spit out molten rock from 4 miles under the surface; afterward, the whole mess settled more than a mile down into the depression where the magma had been.

Magma still feeds hot springs in the caldera. Earthquakes in 1980 marked the beginning of new activity that has included shifts in the position of hot springs and swarms of other small earthquakes. Geologists say it probably indicates that magma is again rising from below, and they suspect the area will erupt again.

Mount Shasta, California: Last known eruption was in 1786. It is believed to erupt every 600 to 800 years, according to the U.S. Geological Survey. The mountain is significant as the incredibly dominant visual element in the Northern California landscape.

Kilauea and Mauna Loa, Hawaii: Each tends to erupt every two or three years; eruptions are non-explosive, allowing these two volcanoes to be among the most studied active volcanoes in the world, according to the U.S. Geological Survey and the University of Hawaii.