Hawaiian Islands Weather details & Aloha paragraphs / April 27-28, 2012

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

Lihue, Kauai –                     82  
Honolulu airport, Oahu –      83 
Kaneohe, Oahu –                 74
Molokai airport –                 83
Kahului airport, Maui –      84  (Record high temperature for Friday – 90 / 1954) 
Kona airport –                    82
Hilo airport, Hawaii –           81

Air Temperatures ranged between these warmest and coolest spots near sea level – and on the highest mountain tops…as of 5pm Friday evening:

Kahului, Maui – 79
Hilo, Hawaii – 73

Haleakala Crater –  50 (near 10,000 feet on Maui)
Mauna Kea –         43 (near 13,800 feet on the Big Island)

Hawaii’s Mountains – Here’s a link to the live web cam on the summit of near 13,800 foot Mauna Kea on the Big Island of Hawaii. This web cam is available during the daylight hours here in the islands…and when there’s a big moon shining down during the night at times. Plus, during the nights you will be able to see stars, and the sunrise and sunset too…depending upon weather conditions. Here's the Haleakala Crater webcam on Maui…although this webcam is not always working correctly.

 Aloha Paragraphs

Strengthening trades…off and on windward
showers this weekend into the new week

Nice surf along our south and west facing beaches

As this weather map shows, we have a near 1031 millibar high pressure system far to the northeast of Hawaii…is moving back west now. At the same time, there's a cold front to the northwest of the islands, which won't arrive, although will weaken our local winds as it pushes a ridge of high pressure closer to the islands. Our local winds will gradually increasing again this weekend…into the new week ahead.

The following numbers represent the most recent wind gusts (mph), along with directions as of Friday evening:

15                 Lihue, Kauai – ENE
22                 Kaneohe, Oahu – ENE
12                 Molokai – NE 
37                 Kahoolawe – ESE
30                 Lipoa, Maui – SE
17                 Lanai – NE
25                 South Point, Big Island – NE

We can use the following links to see what’s going on in our area of the north central Pacific Ocean.  Here's the latest NOAA satellite picture – the latest looping satellite image…and finally the latest looping radar image for the Hawaiian Islands. 

Here are the latest 24-hour precipitation totals (inches) for each of the islands as of Friday evening:
 
1.00               Mount Waialeale, Kauai
2.51               Kahana, Oahu
0.00               Molokai
0.02               Lanai
0.00               Kahoolawe
0.65               Puu Kukui, Maui
0.48               Kealakomo, Big Island  

Sunset Commentary:  A near 1031 millibar high pressure system remains in place far to the northeast of the state Friday evening…although is now moving back to the west. A cold front, which has stalled in its approach to the islands to our northwest, is shifting back to the northwest now too. Our winds are now blowing from the trade winds direction statewide. These trade winds will carry a few showers into the windward sides on those eastern islands. The trade winds will strengthen this weekend, bringing back generally normal weather to our islands, into the new work week ahead.

Here in Kula, Maui at 515pm, skies were partly cloudy with an air temperature of 66.9F degrees. As mentioned above, a late season cold front is located northwest of Hawaii, as shown on this satellite image. The high pressure system to our northeast is now migrating back into the central Pacific…eventually into the area north of Hawaii. As the high pressure cell moves west, and pushes the cold front away, our trade winds will fill back into the entire state. This in turn will put us into a long lasting trade wind weather pattern this weekend through all of the next week. Small craft wind advisories are now in effect for those windiest locations, both coastal and channel waters…around Maui County and the Big Island.

Meanwhile, in the marine environment, south swell waves coming up from the southern hemisphere will bring elevated surf conditions along our south and west facing leeward beaches this weekend…although not large enough to trigger a high surf advisory. We'll find a very common trade wind weather pattern setting up shop here in our area, with lots of white caps on the ocean surface surrounding the Hawaiian Islands. The mornings will have the lightest winds, while the afternoons will exhibit the strongest conditions. The leeward sides will have those waves I was referring to above, although generally lighter winds.

I had a meeting at the Pacific Disaster Center in Kihei, and then a nice long lunch at a restaurant that used to be called Sea Watch in Wailea. This restaurant has a fabulous view of the ocean, and sits on a golf course…all very nice. I'm home now, and will take my fast walk in a few minutes, before having dinner, and then heading down to a friends house, where a few folks are gathering for a drink and conversation. I'll be back at this computer Saturday morning with your next new weather narrative. I hope you have a great Friday night wherever you happen to be spending it! Aloha for now…Glenn.

Interesting:   Seawater is water from a sea or ocean.  On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L). This means that every kilogram (roughly one liter by volume) of seawater has approximately 35 grams (1.2 oz) of dissolved salts (predominantly sodium (Na+) and chloride (Cl−) ions).

A clear change in salinity has been detected in the world's oceans, signaling shifts and acceleration in the global rainfall and evaporation cycle tied directly to climate change. In a paper published Friday (April 27) in the journal Science, Australian scientists from the Commonwealth Scientific and Industrial Research Organization (CSIRO) and Lawrence Livermore National Laboratory reported changing patterns of salinity in the global ocean during the past 50 years, marking a clear symptom of climate change.

Although the vast majority of seawater has a salinity of between 3.1% and 3.8%, seawater is not uniformly saline throughout the world. Where mixing occurs with fresh water runoff from river mouths or near melting glaciers, seawater can be substantially less saline.

The most saline open sea is the Red Sea, where high rates of evaporation, low precipitation and river inflow, and confined circulation result in unusually salty water. The salinity in isolated bodies of water (for example, the Dead Sea) can be considerably greater still.

Lead author Paul Durack said that by looking at observed ocean salinity changes and the relationship between salinity, rainfall and evaporation in climate models, they determined the water cycle has become 4 percent stronger from 1950-2000.

This is twice the response projected by current generation global climate models. "These changes suggest that arid regions have become drier and high rainfall regions have become wetter in response to observed global warming," said Durack, a post-doctoral fellow at Lawrence Livermore National Laboratory.

Scientists monitor salinity changes in the world's oceans to determine where rainfall has increased or decreased. With a projected temperature rise of 3 degrees Celsius by the end of the century, the researchers estimate a 24 percent acceleration of the water cycle is possible.

Scientists have struggled to determine coherent estimates of water cycle changes from land-based data because surface observations of rainfall and evaporation are sparse. According to the team, global oceans provide a much clearer picture.

"Warming of the Earth's surface and lower atmosphere is expected to strengthen the water cycle largely driven by the ability of warmer air to hold and redistribute more moisture." He said the intensification is an enhancement in the patterns of exchange between evaporation and rainfall, and with oceans accounting for 71 percent of the global surface area, the change is clearly represented in ocean surface salinity patterns.

In the study, the scientists combined 50-year observed global surface salinity changes with changes from global climate models and found "robust evidence of an intensified global water cycle at a rate of about 8 percent per degree of surface warming," Durack said.

Durack said the patterns are not uniform, with regional variations agreeing with the "rich get richer" mechanism, where wet regions get wetter and dry regions drier. He said a change in freshwater availability in response to climate change poses a more significant risk to human societies and ecosystems than warming alone.