Hawaiian Islands Weather Details & Aloha Paragraphs / May 21-22, 2018

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

82 – 74  Lihue, Kauai
85 – 75  Honolulu, Oahu
82 – 74  Molokai AP
82 – 70  Kahului AP, Maui
86 – 73  Kailua Kona
82 – 69  Hilo AP, Hawaii

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

0.63  Mount Waialeale, Kauai
0.65  Moanalua RG, Oahu
0.11  Molokai
0.00  Lanai
0.01  Kahoolawe
0.36  West Wailuaiki, Maui
2.00  Saddle Quarry, Big Island

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

28  Port Allen, Kauai
42  Oahu Forest NWR, Oahu
31  Molokai
35  Lanai
37  Kahoolawe
31  Kahului AP, Maui
38  Waikoloa, 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

High pressure northwest through northeast…with troughs just north and west

Deeper clouds over Kauai…thunderstorms far south

Clear to partly cloudy…cloudy areas locally

A few showers over the islands…and offshore
Looping image

 

Here’s the latest VOG Forecast Animation

Here’s the Vog Information website

Trace ashfall possible from Kilauea Volcano…South Big Island

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

 

~~~ Hawaii Weather Narrative ~~~

 

Broad Brush Overview: An elongated zone of moderately strong high pressure, located well northwest through northeast of the islands will weaken…as a cold front approaches from the north. This cold front will stall north of the islands, and a new strong high pressure cell will build through the second half of the week. This will keep our trades going through this week into early next week.

Details: Satellite imagery shows a low aloft west of Kauai, with a ridge aloft over the islands. The ridge will keep the atmosphere relatively stable, with most showers focused over the windward areas. Leeward beaches will remain mostly dry except for afternoon showers over the leeward slopes of the Big Island and east Maui. The southwest flow aloft will carry some high cirrus clouds over the islands.

>>> Meanwhile, close monitoring of Kilauea on the Big Island continues, as Hawaii Volcano Observatory personnel indicate that additional steam-driven explosions are possible at any time. If this occurs…an Ashfall Advisory or Warning would likely become necessary then.

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

Marine Environmental Conditions: Strong trades associated with high pressure north, are forecast to hold through much of the week. Strongest winds are expected over the channels east of Oahu, south of the Big Island, and Maalaea Bay. A weakness within the ridge to our north is forecast to develop Tuesday, as a front passes by far north of the area, which may cause our strong trades to weaken slightly for a brief period.

Two overlapping south-southwest swells from a couple of sources have arrived. Surf heights associated with this swell should stay just below the surf advisory level for south facing shores. Another similar pulse out of the south-southwest is expected by mid-week or Thursday.

Surf from the north-northwest swell will continue to lower. Another small north-northwest pulse could bring the surf by again by mid-week along north facing shores.

Surf along east facing shores will remain rough, as strong trades hold locally and upstream. Heights should remain below advisory levels. Heights should trend down slightly through the first half of this week, as a front passes to the north and the large area of upstream strong winds weaken.

The models depict plenty of energy setting up within Hawaii’s swell window from the Tasman Sea. If the generating storms evolve as predicted, the associated surf should make it to the local Hawaiian waters toward the end of the month, around 5/29.

 

World-wide Tropical Cyclone activity

Here’s the Monday Pacific Disaster Center (PDC) Weather Wall Presentation covering Tropical Cyclone 02A…the Arabian Sea

Here’s the Monday Pacific Disaster Center (PDC) Weather Wall Presentation covering a tropical disturbance, being referred to as Invest 90L…in the Caribbean Sea…south of Cuba

 

>>> Atlantic Ocean: No active tropical cyclones

>>> Caribbean Sea: No active tropical cyclones

>>> Gulf of Mexico: No active tropical cyclones

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: No active tropical cyclones

Tropical cyclone formation is not expected during the next 5 days.

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: No active tropical cyclones

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

>>> Northwest Pacific Ocean: No active tropical cyclones

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

Tropical Cyclone 02A

JTWC textual Warning
JTWC graphical track map
NOAA satellite image

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


Interesting: East vs West Coast Earthquakes – Why was an earthquake in Virginia felt at more than twice the distance than a similar-sized earthquake in California? The answer is one that many people may not realize. Earthquakes east of the Rocky Mountains can cause noticeable ground shaking at much farther distances than comparably-sized earthquakes in the West.

A magnitude 5.8 earthquake in 2011 in Mineral, Virginia, was felt up to 600 miles from the epicenter. Tens of millions of people in the eastern United States and southeastern Canada felt this earthquake.

For comparison, a magnitude 6.0 earthquake in 2014 in Napa, California, was felt only as far as 250 miles from the epicenter. Despite the Napa earthquake releasing about twice as much energy as the Virginia earthquake and causing much more damage near the epicenter, it wasn’t felt nearly as far away.

As another example, the magnitude 4.1 earthquake that occurred in December 2017 near Dover, Delaware, was felt approximately 200 miles from the epicenter. The region that felt this earthquake is about the same size as that of the much larger California event, which released about 700 times more energy.

Scientists are researching a variety of factors that influence regional differences in the intensity and effects of earthquakes. Some of the factors have to do with the nature of the underlying tectonic plates and their geologic history. Others are connected to the size and age of buildings.

Seismic Waves Can Travel Farther in the East

Eastern North America has older rocks, some of which formed hundreds of millions of years before those in the West. These older formations have been exposed to extreme pressures and temperatures, making them harder and often denser. Faults in these older rocks have also had more time to heal, which allows seismic waves to cross them more effectively when an earthquake occurs.

In contrast, rocks in the West are younger and broken up by faults that are often younger and have had less time to heal. So when an earthquake occurs, more of the seismic wave energy is absorbed by the faults and the energy doesn’t spread as efficiently.

More Vulnerable Infrastructure in the East

Many of the older structures in the East, such as buildings and bridges built before the 1970s, were not designed to endure earthquakes and therefore may not fare well. The recent earthquakes that struck near Christchurch, New Zealand showed the damage that infrequent earthquakes can do to a region with older structures. With that said, modern buildings are being constructed to newer design standards, and there has been progress in retrofitting many older buildings in the East. In the West, older structures are often retrofitted, and new structures are designed to withstand strong shaking.

Furthermore, smaller structures such as houses could experience stronger and more damaging shaking in the East. Earthquakes in the East tend to cause higher-frequency shaking—faster back and forth motion—compared to similar events in the West. Shorter structures are more susceptible to damage during fast shaking, whereas taller structures are more susceptible during slow shaking.

Surprising Level of Shaking in Washington, DC

An example of the earthquake hazard in the eastern U.S. is provided by the surprising level of high-intensity ground shaking that occurred in Washington, DC, during the 2011 Virginia earthquake. This shaking caused well-publicized damage to some historic buildings, even though the earthquake was moderate in size and its epicenter was 80 miles from the city.

To learn more, USGS scientists deployed 27 temporary seismometers throughout DC to study variations in the strength of earthquake ground shaking. The instruments recorded ground motions from 30 earthquakes around the world during the 10 months they were in place.

Scientists confirmed that shaking is amplified in the parts of DC underlain by a thin layer of sediments compared to areas built on more solid, harder bedrock. This is because the energy in the seismic waves can move the lighter, weaker sediments more easily than the harder bedrock, and that energy gets “trapped” and echoes multiple times within the sediments.

While this amplification effect has been well documented in some western cities, including Seattle, Los Angeles and San Francisco, this is the first study that directly measures the effect in the nation’s capital. It was previously suspected to occur in Washington, DC, and had been found in other cities such as Boston.

Other major cities in the central and eastern United States with similar geology that could lead to amplified ground shaking include Trenton, New Jersey; Wilmington, Delaware; Baltimore, Maryland; Richmond, Virginia; and Columbia, South Carolina. Similar deposits also underlie cities in the Mississippi Valley and Gulf Coast, notably Memphis, Tennessee, near the New Madrid Seismic Zone.

The new results about amplification and the more efficient energy transmission in the East are part of an increased understanding and awareness of earthquake hazards in central and eastern U.S. cities. This information is especially useful to engineers and architects when designing buildings and retrofitting existing structures.

Challenges of Assessing Earthquake Hazards in the East

The geology of the eastern United States and the relatively sparse history of earthquakes to study make it difficult for scientists to assess how frequently earthquakes will occur and how large they can be. Eastern earthquakes are more of a mystery because they do not take place at a plate boundary where most other earthquakes originate. Scientists do not fully understand the state of stress within tectonic plates, and they are studying how stresses accumulate and evolve and how earthquakes are triggered.

Scientists also do not know precisely where most active faults are located in the East. Most faults have not had major earthquakes or movement in the past few million years, and the faults that are active may only have earthquakes every few thousand or tens of thousands of years. Furthermore, any evidence of past earthquakes on the land’s surface in the eastern U.S. is often obscured by vegetation or is more subdued because of erosion.

Conversely, the West has more active faults and many areas with sparse vegetation, meaning earthquakes can leave clear markings that inform research on earthquake history, size and effects.

Ongoing Research

The National Science Foundation and the USGS recently added new seismic stations in the central and eastern United States, creating a more robust network that augments the monitoring by university partners. USGS scientists also are working with university collaborators on several research projects. For example, they are searching parts of Virginia and the Carolinas for evidence of strong earthquake shaking in the past, monitoring earthquakes and studying faults near the 2011 earthquake in Virginia and the 1886 earthquake in Charleston, South Carolina, and conducting detailed studies of the seismically active central Virginia region.

Scientists Can’t Predict Earthquakes

As far as predicting earthquakes, no reliable short-term earthquake prediction method has ever been developed. Nor do scientists expect to develop a method in the foreseeable future.  However, using scientific data—such as fault locations and patterns of earthquakes over many years—probabilities can be calculated for future earthquakes, and that information is used in development of building codes. Furthermore, the USGS and its partners are working to develop a prototype Earthquake Early Warning System for the West Coast of the U.S. called ShakeAlert. The system does not predict earthquakes, but once an earthquake happens, it could provide a few seconds to tens of seconds of warning before seismic waves arrive and cause strong shaking.

More Earthquakes in the West

The western United States lies along the boundaries of major tectonic plates that make up the Earth’s crust—the North American Plate and the ocean plates to the west. These plates are moving against each other, breaking up the crust along many faults like the San Andreas Fault. Faults in the East are less active and lie entirely within the North American Plate.