April 17-18 2008

Air Temperatures
The following maximum temperatures were recorded across the state of Hawaii Thursday: 

Lihue, Kauai – 77
Honolulu, Oahu – 80
Kaneohe, Oahu – 80
Kahului, Maui – 83
Hilo, Hawaii – 81
K
ailua-Kona, Hawaii – 84

Air Temperatures 
ranged between these warmest and coolest spots near sea level at 4 p.m. Thursday afternoon:

Kailua-kona – 82F
Barking Sands, Kauai – 76   

Precipitation Totals
The following numbers represent the largest precipitation totals (inches) during the last 24 hours on each of the major islands, as of
Thursday afternoon:

1.94 PORT ALLEN, KAUAI
0.35 WHEELER FIELD
, OAHU
0.21 MOLOKAI
0.10 LANAI
0.00 KAHOOLAWE
0.01
ULUPALAKUA, MAUI
0.09
PAHOA
, BIG ISLAND

Weather Chart – Here’s the latest (automatically updated) weather map showing a 999 millibar low pressure system to our NNW. This low will be moving away now, with high pressure establishing itself to the NE and NW. Our recent light SE winds will gradually become trade winds into Saturday.

Satellite and Radar Images:
To view the cloud conditions we have here in Hawaii, please use the following satellite links, starting off with the 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…out from the islands. 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 cloud conditions.


Aloha Paragraphs



The image “http://farm3.static.flickr.com/2308/2386180929_c05ccd6762.jpg?v=0” cannot be displayed, because it contains errors.
White sand and blue water of windward Oahu 
Photo Credit: flickr.com


A low pressure system in our area will keep our winds light today, with returning trade winds Friday. Our normal trade winds have veered around to the southeast and south-southeast recently…due to the close proximity of the low to the northwest of Kauai. These lighter winds have kept somewhat muggy conditions in place, with daytime temperatures feeling very warm near the beaches, especially in those areas out from under cloud cover. The SE winds have carried volcanic haze up from the Big Island to other parts of the state as well. The trade winds will rebound later Friday, and remain active through the weekend…continuing on into next week.

The Kauai end of the island chain saw the most showers Thursday…due to its closeness to the low pressure system. Generally though, we saw an increase in afternoon convective clouds, but not very many showers over the islands from Oahu down through the Big Island. Satellite imagery showed some towering cumulus clouds, and thunderstorms forming near Kauai Thursday morning, which was evidence of the cold air aloft associated with the dynamic low pressure area. As this low pressure area remains quite close through Thursday, there will be the chance of showers breaking out. As this weather feature moves away Friday, our local air mass will lose its shower aspects.


It’s Thursday evening as I begin updating this last section of today’s narrative.
 
The low pressure system, mentioned above, will be moving out of our area later Friday. This in turn will allow the refreshing trade winds to return into the weekend. These light to moderately strong trade winds will help to clear the humid air, with more comfortable conditions returning then. There will continue to be some volcanic haze in places, although most concentrated down on the Big Island as usual. As there are two volcanic emission points now, it is difficult for that southernmost island to escape the dreaded vog these days. The computer forecast models suggest that the trade winds will carry on right into next week, with generally fair weather forecast then statewide.

Thursday was a pretty good day, although most islands saw sun dimming and filtering high clouds above, and muggy and hazy air conditions below. The heaviest showers were restricted to the island of Kauai, with just a few light to moderate afternoon showers elsewhere. It looks like Friday will see the return of the trade winds, which will become even better established this weekend. This new air flow will ventilate the haze away in most areas, or at least begin to do that from Kauai down through Maui. At the same time, we should see the return of a few windward biased showers as well. This weekend looks like a nice one, with favorable weather conditions continuing right on into next week.

I’ll be back again very early Friday morning with your next new weather narrative. I hope you have a great Thursday night wherever you happen to be spending it! Aloha for now…Glenn.

Interesting: A thick layer of yellow dust blanketed houses and cars in the Iraqi capital Thursday as a heavy sandstorm over central Iraq sent dozens of residents to hospitals with breathing difficulties. The spring storm, one of the worst in years, forced the closure of the Baghdad International Airport. It also appeared to hamper military flights. None of the helicopter patrols that regularly roar over the city of 6 million people seemed to be airborne. Many shops in the city were closed, and only a few cars were seen on the deserted streets. AP Television News footage also showed Iraqi traffic policemen wearing masks over their mouths as protection from the dust whipped up by the hot winds.

Interesting2: Planet Earth continues to run a fever. Last month was the warmest March on record over land surfaces of the world and the second warmest overall worldwide. For the United States, however, it was just an average March, the National Oceanic and Atmospheric Administration reported Thursday.NOAA’s National Climatic Data Center said high temperatures over much of Asia pulled the worldwide land temperature up to an average of 40.8 degrees, 3.2 degrees warmer than the average in the 20th century. While Asia had its greatest January snow cover this year, warm March readings caused a rapid melt and March snow cover on the continent was a record low. Global ocean temperatures were the 13th warmest on record, with a weakening of the La Nina conditions that cool the tropical Pacific Ocean. Overall land and sea surface temperatures for the world were second highest in 129 years of record keeping, trailing only 2002, the agency said. Warming conditions in recent decades have continued to raise concern about global climate change, which many weather and climate experts believe is related to gases released into the atmosphere by industrial and transportation processes. The climate center said that for the 48 contiguous United States it was about average, ranking as the 63rd warmest March in 113 years of record keeping.

Interesting3: Major floods striking America’s heartland this week offer a preview of the spring seasonal outlook, according to NOAA’s National Weather Service. Several factors will contribute to above-average flood conditions, including record rainfall in some states and snow packs, which are melting and causing rivers and streams to crest over their banks. This week, more than 250 communities in a dozen states are experiencing flood conditions. The science supporting NOAA’s short-term forecasts allows for a high level of certainty. National Weather Service forecasters highlighted potential for the current major flood event a week in advance and began working with emergency managers to prepare local communities for the impending danger.  “We expect rains and melting snow to bring more flooding this spring,” said Vickie Nadolski, deputy director of NOAA’sNational Weather Service. “Americans should be on high alert to flood conditions in your communities. Arm yourselves with information about how to stay safe during a flood and do not attempt to drive on flooded roadways — remember to always turn around, don’t drown.”

Interesting4: Hurricanes in some areas, including the North Atlantic, are likely to become more intense as a result of global warming even though the number of such storms worldwide may decline, according to a new study by MIT researchers.

Kerry Emanuel, the lead author of the new study, wrote a paper in 2005 reporting an apparent link between a warming climate and an increase in hurricane intensity. That paper attracted worldwide attention because it was published in Nature just three weeks before Hurricane Katrina slammed into New Orleans.

Emanuel, a professor of atmospheric science in MIT’s Department of Earth, Atmospheric and Planetary Sciences, says the new research provides an independent validation of the earlier results, using a completely different approach. The paper was co-authored by postdoctoral fellow Ragoth Sundararajan and graduate student John Williams and appeared last week in the Bulletin of the American Meteorological Society.

While the earlier study was based entirely on historical records of past hurricanes, showing nearly a doubling in the intensity of Atlantic storms over the last 30 years, the new work is purely theoretical. It made use of a new technique to add finer-scale detail to computer simulations called Global Circulation Models, which are the basis for most projections of future climate change.

Interesting5: The jet stream — America‘s stormy weather maker — is creeping northward and weakening, new research shows. That potentially means less rain in the already dry South and Southwest and more storms in the North. And it could also translate into more and stronger hurricanes since the jet stream suppresses their formation. The study’s authors said they have to do more research to pinpoint specific consequences. From 1979 to 2001, the Northern Hemisphere’s jet stream moved northward on average at a rate of about 1.25 miles a year, according to the paper published Friday in the journal Geophysical Research Letters.

The authors suspect global warming is the cause, but have yet to prove it. The jet stream is a high-speed, constantly shifting river of air about 30,000 feet above the ground that guides storm systems and cool air around the globe. And when it moves away from a region, high pressure and clear skies predominate.  Two other jet streams in the Southern Hemisphere are also shifting poleward, the study found. The northern jet stream "is the dominant thing that creates weather systems for the United States,” said study co-author Ken Caldeira, a climate scientist at the Carnegie Institution of Washington in Stanford, Calif. "Bascially look south of where you are and that’s probably a good guess of what your weather may be like in a few decades.”

The study looked at the average location of the constantly moving jet stream and found that when looked at over decades, it has shifted northward. The study’s authors and other scientists suggest that the widening of the Earth’s tropical belt — a development documented last year — is pushing the three jet streams toward the poles.

Climate models have long predicted that with global warming, the world’s jet streams would move that way, so it makes sense to think that’s what happening, Caldeira said. However, proving it is a rigorous process, using complex computer models to factor in all sorts of possibilities. That has not been done yet.

A rate of 1.25 miles a year "doesn’t sound like much, but that works out to about 18 feet per day,” Caldeira said. "If you think about climate zones shifting northward at this rate, you can imagine squirrels keeping up. But what are oak trees going to do?