August 7-8, 2009
Air Temperatures – The following maximum temperatures were recorded across the state of Hawaii Friday afternoon:
Lihue, Kauai – 82
Honolulu, Oahu – 90
Kaneohe, Oahu – 84
Kahului, Maui – 88
Hilo, Hawaii – 81
Kailua-kona – 88
Air Temperatures ranged between these warmest and coolest spots near sea level – and on the highest mountains…at 5 p.m. Friday evening:
Honolulu, Oahu – 85F
Lihue, Kauai – 78
Haleakala Crater – 57 (near 10,000 feet on Maui)
Mauna Kea summit – 45 (near 14,000 feet on the Big Island)
Precipitation Totals – The following numbers represent the largest precipitation totals (inches) during the last 24 hours on each of the major islands, as of Friday afternoon:
0.28 Mount Waialaele, Kauai
0.14 Palisades, Oahu
0.00 Molokai
0.00 Lanai
0.00 Kahoolawe
0.53 Puu Kukui, Maui
0.56 Waiakea Uka, Big Island
Marine Winds – Here’s the latest (automatically updated) weather map showing a 1030 millibar high pressure system to the north-northeast of the islands. This high pressure cell, along with its associated ridge to our north, will keep the trade winds blowing through Sunday.
Satellite and Radar Images: To view the cloud conditions we have here in Hawaii, please use the following satellite links, starting off with this Infrared Satellite Image of the islands to see all the clouds around the state during the day and night. This next image is one that gives close images of the islands only during the daytime hours, and is referred to as a Close-up visible image. This next image shows a larger view of the Pacific…giving perspective to the wider ranging cloud patterns in the Pacific Ocean. Finally, here’s a Looping IR satellite image, making viewable the clouds around the islands 24 hours a day. To help you keep track of where any showers may be around the islands, here’s the latest animated radar image.
Hawaii’s Mountains – Here’s a link to the live webcam on the summit of near 14,000 foot Mauna Kea on the Big Island of Hawaii. The tallest peak on the island of Maui is the Haleakala Crater, which is near 10,000 feet in elevation. These two webcams are available during the daylight hours here in the islands…and when there’s a big moon rising just after sunset for an hour or two! Plus, during the nights and early mornings you will be able to see stars, and the sunrise too…depending upon weather conditions.
Tropical Cyclone activity in the eastern and central Pacific – Here’s the latest weather information coming out of the National Hurricane Center, covering the eastern north Pacific. You can find the latest tropical cyclone information for the central north Pacific (where Hawaii is located) by clicking on this link to the Central Pacific Hurricane Center. Here’s a tracking map covering both the eastern and central Pacific Ocean. A satellite image, which shows the entire ocean area between Hawaii and the Mexican coast…can be found here.
Aloha Paragraphs
Hurricane Felicia approaches from the east
Little change is expected in the strength of our local trade winds through the weekend…with the influence of weakening tropical cyclone Felicia taking over after the weekend. A 1030 millibar high pressure system remains in place to the north-northeast of Hawaii Friday night. This trade wind producing high pressure cell is shown on this weather map. A small craft wind advisory continues to cover only the windiest areas around Maui County and the Big Island at this time. As whatever is left of Felicia moves into our area, we will very likely see small craft wind advisories, and perhaps even gale warnings in the major channels. There may be a tropical storm watch or warnings going up this weekend as well.
A typical trade wind weather pattern will keep just a few showers falling along our windward sides for the time being…with most leeward areas remaining dry. When tropical cyclone Felicia pushes close to the state of Hawaii starting Monday…we could see very rainy weather arrive around the Big Island and Maui, and then moving further up the island chain to the other islands. Once this potentially rainy weather moves west past the state later Tuesday or early Wednesday, we will return to favorably inclined weather conditions statewide. By the way, trying to put a positive spin on the prospect of rainfall, we’re hoping that there won’t be any flash flooding, but we could use the precipitation…the danger of course is too much of a good thing!
Hurricane Felicia remains active in the eastern Pacific Friday night…and actually gained strength temporarily. This kept the hurricane classified as a category 2 tropical cyclone. This system will begin to drop in strength going forward, as it moves into our central Pacific Saturday morning. The current forecast keeps Felicia a hurricane through Saturday, before weakening into a tropical storm Sunday. Here’s a tracking map, showing Felicia heading towards the Aloha state. Here’s a satellite image showing this soon to be weakening hurricane in relation to the Hawaiian Islands.
The sustained winds Friday evening were blowing at 90 knots…which translates into 104 mph. The hurricane is expected to gradually weaken throughout the rest of its life cycle. The latest National Hurricane Center (NHC) forecast shows Felicia becoming a weaker hurricane when it moves into our central Pacific area early Saturday morning. The good news is that the forecast drops the system down into a tropical storm as it approaches the Big Island end of the chain…and then further weakening it to a tropical depression as it moves by to the south of the Aloha state.
If the current NHC forecast remains true, with a weakening tropical storm, or a tropical depression moving over the southern islands…we could see the following influences. The first sign of the storm would be rising surf along our east facing shores on Sunday…which could bring dangerously large breaking waves to our beaches. As Felicia gets closer, we could see locally blustery weather…depending upon the storm’s strength and location then. Finally, if this tropical system were to come in over, or close to the southern part of the state as expected, we would see increasing clouds, and potentially heavy flooding rainfall Monday into Tuesday.
Note: The NWS office in Honolulu has issued a Flood Potential Outlook for the state of Hawaii, associated with tropical cyclone Felicia. They are expecting heavy rains and flash flooding this coming Monday through the middle of the week. Their disclaimer says: "AT THIS POINT…THERE IS CONSIDERABLE UNCERTAINTY IN THE LOCATIONS THAT WILL BE AFFECTED…THE ONSET AND DURATION OF HEAVY RAINS…AND THE RAINFALL AMOUNTS THAT ARE EXPECTED TO OCCUR. ALL OF THESE ARE DEPENDENT ON THE TRACK FELICIA ULTIMATELY TAKES."
It’s Friday evening here in Kihei, Maui, as I begin writing this last part of this last part today’s narrative. If you had a chance to read down through this entire page, you know that there is a strong hurricane in the eastern Pacific, which is getting ready to cross over into our central Pacific soon. The good news is that as it moves over a cooler ocean surface, and pushes westward, it will also run into stronger winds at upper levels of the atmosphere. These are both conditions that inhibit further strengthening of a storm…and usually cause a rather pronounced weakening. Nonetheless, we should continue to monitor the progress of this storm. Here’s a great satellite image showing the big picture, with Felicia and the islands.
~~~ Everything seems to be turning out according to script at this point, which is generally good news…at least in terms of not being hit by a major hurricane. Nonetheless, the three things we need to pay most attention to at this point, would be the rising surf along our east shores, the potentially blustery weather…and the threat of possible heavy flooding rains. These conditions are pointed out in the paragraphs above, although there remains the chance of deviations of these expected conditions. Thus, we all need to pay close attention to this approaching tropical cyclone, as it heads in our direction.
~~~ By the way, the number of page impressions that this website received Thursday, due to the high traffic count of those folks who were looking for information on hurricane Felicia…was 23,507. This was one of the largest numbers since the last big weather event happened here in the islands. Of those, there were 265 clicks on my google ads, which is one way that I create funding for keeping this website updated on a daily basis. Friday’s total was 20,854 page impressions, with 445 google clicks…thank you!
~~~ I’ll be back early Saturday morning with your next new weather narrative. I’ll have more of the latest information on hurricane Felicia then. I hope you have a great Friday night from wherever you happen to be reading this narrative! Aloha for now…Glenn.
Interesting: Scientists have placed high-tech "spiders" inside and around the mouth of Mount St. Helens, one of the most active volcanoes in the United States. Networks such as these could one day be used to respond rapidly to an impending eruption. On July 14, 2009, these spider pods were lowered by cable from a helicopter hovering about 100 feet up and gently put in hot spots inside and around the volcano crater.
"This project demonstrates that a low-cost sensor network system can support real-time monitoring in extremely challenging environments," said WenZhan Song of Washington State University Vancouver. Song is the principal investigator for this NASA-funded technology research project, which also draws on participation from the U.S. Geological Survey and from NASA’s Jet Propulsion Laboratory, Pasadena, Calif.
These robotic emissaries were built to go where no human can and operate in extreme temperatures and treacherous terrain. Fifteen pods form a virtual wireless network, communicating with each other and the Earth Observing-1 (EO-1) satellite, operated by NASA’s Goddard Space Flight Center, in Greenbelt, Md.
"Taking data from the ground onsite and from above by satellite gives you a great picture of what is going on inside the volcano," said Steve Chien, principal scientist for autonomous systems at JPL. Each pod contains a seismometer to detect earthquakes; a GPS receiver to pinpoint the exact location and measure subtle ground deformation; an infrared sounder to sense volcanic explosions; and a lightning detector to search for ash cloud formation.
The main instrument box is the size and shape of a microwave oven. It sits on top of a three-legged tripod, which is why scientists call them spiders. The pods are powered by batteries that can last for at least a year. "With these high-tech instruments, we can rapidly respond during periods of volcanic unrest to supplement our permanent monitoring network or quickly replace damaged stations without excessive exposure to personnel," said Rick LaHusen, an instrumentation engineer with the U.S. Geological Survey’s Cascades Volcano Observatory, Vancouver, Wash.
In 1980, a tremendous eruption at Mount St. Helens caused considerable loss of life and damage. More recently, in 2004, the volcano came back to life and erupted more than 26 billion gallons of lava, accompanied by a series of explosions that hurled rock and ash far from the vent.
If eruptions like these ever occur again, a sensor network could be quickly put in place to provide valuable real-time information to scientists and emergency services. This work is part of NASA’s plan to develop a sensor web to provide timely data and analyses for scientific research, natural hazard mitigation, and the exploration of other planets in this solar system and beyond.
"We hope this network will provide a blueprint for future networks to be installed on many of the world’s unmonitored active volcanoes, so educated and reliable estimates can be made when a town or a village needs to be evacuated to reduce the risk to life and property," said Project Manager Sharon Kedar of JPL.
Chien said, "Hostile environments like Mount St. Helens are proving grounds for future space missions, such as to Mars, where we may someday have similar sensor networks to track a meteor strike, dust storm or Mars quake, as a virtual scientist on the ground." Song said, "The design and deployment experiences will help us understand challenging environments and inspire new discoveries."
Interesting2: Scientists now know how a natural hydrocarbon emitted in large quantities by plants can be transformed into light-scattering aerosols that contribute to haze and influence climate. The finding will improve models of atmospheric chemistry and climate and may help explain puzzling field observations in some parts of the world, the researchers report. Worldwide, plants release more than 550 million metric tons of the hydrocarbon isoprene into the atmosphere each year.
But scientists have disagreed about the particular chain of chemical reactions that transform isoprene into haze-forming aerosols, says Fabien Paulot, an atmospheric chemist at the California Institute of Technology in Pasadena. Now, lab tests by Paulot and his colleagues, reported in the Aug. 7 Science, have identified a new class of substances long suspected to form as an intermediate in those reactions but never before seen.
The team created the chemicals, called dihydroxyepoxides, by placing isoprene and hydrogen peroxide in an 800-liter bag of unpolluted air and then illuminating the mix with ultraviolet light. The UV light stimulated chemical reactions, just as sunlight would, and the hydrogen peroxide served as a source of hydroxyl radicals — highly reactive compounds known as "the detergent of the atmosphere," Paulot says.
Isoprene and hydroxyl radicals reacted to form dihydroxyepoxides via two separate chemical processes. Because the resulting epoxides are highly soluble, they readily dissolve into droplets of moisture in the air to form organic-rich aerosols, Paulot says.
Interesting3: Harvard University scientists are predicting some forms of air pollution could increase significantly across the West as more of the region’s wild lands burn as a result of rising temperatures. Smoke from wildfires contains two main kinds of carbon particles: black soot, or elemental carbon, and lighter-colored particles, called organic carbon aerosols, which are a mix of chemicals.
"In large quantities, downwind of fires, organic carbon aerosols are hazardous," said senior research fellow Jennifer Logan, who led a study examining rising wildfire rates and the impact on air quality. "The particles irritate lung tissue and the chemicals they carry are toxic. But even at low concentrations, these aerosols may be dangerous. We don’t know. There is no known threshold where damage begins."
Interesting4: Three major glaciers in Alaska and Washington state have thinned and shrunk dramatically, clear signs of a warming climate, according to a study released Thursday by the U.S. Geological Survey. The three glaciers — Gulkana and Wolverine in Alaska and South Cascade in Washington — are considered benchmarks for those in alpine and maritime climates because they closely parallel other glaciers in their regions.
They have also been the subject of close scientific scrutiny since 1957. "These are the three glaciers in North America that have the longest record of mass change," said Shad O’Neel, a United States Geological Survey glaciologist in Anchorage who was one of the study authors.
"All three of them have a different climate from the other two, yet all three are showing a similar pattern of behavior, and that behavior is mass loss." Scientists are keeping a close watch on melting glaciers, as a rise in sea-levels would threaten coastal and low-lying areas around the world.
The latest study compares records of snow and ice thickness and densities over the years, the factors used to calculate mass. The glaciers have lost mass as melting outpaced new snow and ice accumulation, and for all three, the losses were especially dramatic over the past 15 years, according to the USGS study.
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