Air Temperatures – The following maximum temperatures (F) were recorded across the state of Hawaii Tuesday…along with the minimums Tuesday:
84 – 73 Lihue, Kauai
85 – 75 Honolulu, Oahu
82 – 72 Molokai AP
86 – 72 Kahului AP, Maui
85 – 73 Kailua Kona
83 – 68 Hilo AP, Hawaii
Here are the latest 24-hour precipitation totals (inches) for each of the islands…as of Tuesday evening:
1.34 Mount Waialeale, Kauai
0.68 Manoa Lyon Arboretum, Oahu
0.06 Puu Alii, Molokai
0.00 Lanai
0.00 Kahoolawe
0.14 Hana AP, Maui
0.24 Honaunau, Big Island
The following numbers represent the strongest wind gusts (mph)…as of Tuesday evening:
28 Port Allen, Kauai – ENE
30 Kuaokala, Oahu – NE
27 Molokai – ENE
27 Lanai – NE
33 Kahoolawe – ENE
32 Kahului AP, Maui – NNE
38 Puu Mali, Big Island – NE
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.
Aloha Paragraphs
A low pressure system over the ocean far to the northeast…
along with its ragged cloud band slipping into the state
A dissipating band of clouds will bring some windward
showers…high clouds to our south and west
Clear to partly cloudy leeward…with the nearby low clouds
associated with a weak frontal cloud band
Showers falling locally – Looping radar image
Small Craft Advisory…for Maalaea Bay, Pailolo Channel,
Alenuihaha Channel, southeast and leeward waters
of the Big Island
~~~ Hawaii Weather Narrative ~~~
Trades winds continuing…with a break beginning Thursday. Here’s the latest weather map, showing the Hawaiian Islands, and the rest of the North Pacific Ocean. We find a high pressure system well offshore to the northeast of the state. At the same time, we see a low pressure system northeast, along with its trailing cloud band near Kauai and Oahu. Trade winds will continue through most of Wednesday, although another cold front approaches the state Thursday. As this happens, we’ll see our winds become lighter, and veer to the southeasterly through Saturday morning. As we know, when the winds swing around to the southeast…we will likely see increased volcanic haze arriving over the smaller islands. The trade winds should return during the weekend, ventilating the vog away then.
Here’s a wind profile…of the offshore waters around the islands – with a closer view
Here’s the Hawaiian Islands Sulfate Aerosol animated graphic – showing vog forecast
The trade winds will keep off and on showers…focused along the windward sides. The leeward beaches will remain generally dry, with a few exceptions here and there at times. Look for an increase in windward showers, brought our way by the decaying cold front into Wednesday, which may spill over into the leeward areas locally. The models go on to suggest another late season cold front approaching the islands by Thursday-Friday. As this weather feature interrupts our trade wind flow, our winds will calm down, and we should see some afternoon clouds with localized upcountry showers developing…some of which may be locally heavy. Then, as the trade winds return over the weekend, frequent showers will gravitate back over to the windward sides into the middle of next week.
Marine environment details: A small craft advisory /SCA/ remains posted for the typically windy waters adjacent to the islands of Maui County and the Big Island, including the Kaiwi Channel through tonight. SCA conditions for all or most of these areas are likely to persist on Wednesda, before winds decrease and veer out of the southeast starting Wednesday night. Forecast models show increasing northeasterly trade winds spreading from west to east over the area this weekend. These winds may reach the SCA criteria near Kauai on Saturday.
A small west-northwest swell will arrive later tonight and continue through Friday. A reinforcing north-northwest swell will persist through the weekend. South swells will maintain surf along south facing shores through Thursday. A new south swell will arrive Friday, peak late Saturday above the seasonal south swell average…and then slowly subside into early next week. While surf will be elevated, we are expected to stay below the high surf advisory criteria. On the east facing shores, the breezy trade winds will continue to produce choppy surf through Wednesday, then taper off as the winds weaken.
Ka’anapali Beach…west Maui
Here on Maui – Before sunrise on this Tuesday morning, we find partly to mostly cloudy skies along the windward coasts and slopes…stretching up over the West Maui mountains. These clouds are dropping a few showers, as the trades carry moisture ashore. Elsewhere around the island, skies were mostly clear. Here in upcountry Kula, it was calm and clear, with an air temperature at my weather tower of 47.8F degrees. At near the same time, the Kahului AP was reporting 74 degrees under mostly cloudy skies, while it was 72 out in Hana…with 45 atop the Haleakala Crater. / Now at near 9am, skies are almost totally cloud free over the island…it’s a beautiful day!
– Early evening, and yes…yet another very nice day we’ve had!
World-wide tropical cyclone activity:
>>> Atlantic Ocean: The last regularly scheduled Tropical Weather Outlook of the 2015 Atlantic hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant. Here’s the 2015 hurricane season summary
Here’s a satellite image of the Atlantic Ocean
>>> Caribbean Sea: The last regularly scheduled Tropical Weather Outlook of the 2015 Atlantic hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant.
>>> Gulf of Mexico: The last regularly scheduled Tropical Weather Outlook of the 2015 Atlantic hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant.
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: The last regularly scheduled Tropical Weather Outlook of the 2015 North Pacific hurricane season…has occurred. Routine issuance of the Tropical Weather Outlook will resume on May 15, 2016. During the off-season, Special Tropical Weather Outlooks will be issued if conditions warrant. Here’s the 2015 hurricane season summary
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: The central north Pacific hurricane season has officially ended. Routine issuance of the tropical weather outlook will resume on June 1, 2016. During the off-season, special tropical weather outlooks will be issued if conditions warrant. Here’s the 2015 hurricane season summary
Here’s a link to the Central Pacific Hurricane Center (CPHC)
>>> South Pacific Ocean: No active tropical cyclones
>>> North and South Indian Oceans / Arabian Sea: No active tropical cyclones
Here’s a link to the Joint Typhoon Warning Center (JTWC)
Interesting: Love that fresh soil smell after a nice rain? – Most of us think of that sweet smell after a storm as the after-effect of rain that has rinsed the air of pollutants and dust. But it turns out that rain also triggers the release of a mist of particles from wet soils into the air, a finding with consequences of its own for how scientists model our planet’s climate and future.
The evidence comes in the form of tiny glassy spheres, less than one-hundredth the width of a human hair, discovered at the Great Plains of Oklahoma after a rainstorm…and put under scrutiny by scientists at several U.S. Department of Energy facilities. The study appears May 2 in Nature Geoscience.
According to the authors, scientists have largely assumed that organic particles from the soil enter the air through erosion by wind or through agricultural work. The effects of rain splash haven’t been part of the discussion.
But the team’s field observations indicate that up to 60 percent of particles that are airborne after a rainstorm in certain areas, such as grasslands and tilled fields, come from the soil. These organic particles are carbon-based and come from decaying vegetation and organisms. The tiny bits of organic matter can hold tremendous sway over our climate, playing a role in the fate of sunlight as it hits Earth.
Captured…freed from the soil by raindrops
It’s not simply that raindrops hit the ground and dislodge some dirt which flies into the air. Rather, as the rain falls, organic matter in the soil dissolves in puddles that form. As more rain falls, the splashing creates air bubbles which mix with the dissolved matter of the soil. The bubbles float upward and quickly burst, releasing into the air a mist of the soil organic compounds.
In the air, the droplets in the mist dry and their contents become solid glassy organic particles. These tiny spheres — made mostly of carbon, oxygen and nitrogen — are about half a micron wide and disperse through the air, sometimes depositing on the ground almost immediately but usually staying aloft for days or weeks, oftentimes traveling thousands of miles.
Such was the case March 27, 2014, in Lamont, Okla., a day after a strong rainstorm swept through the region. As part of an exploratory study, researchers with the Gilles team gathered samples of airborne particles at DOE’s Atmospheric Radiation Measurement Climate Research Facility. Under the microscope, scientists quickly determined there was something special about the air sample: It was full of tiny, spherical, glassy particles.
They were so out of place that when Gilles first examined the particles under the microscope, she scribbled in her lab notebook, “Something is wrong with these samples.”
Her group and the Laskin group at EMSL then deployed a set of advanced chemical imaging tools to analyze the particles, including a synchrotron-based X-ray absorption microscope, a scanning electron microscope, a helium ion microscope and a transmission electron microscope. More than a year of intensive chemical analysis showed that the particles were definitely composed of organic matter from the soil.
The same was true of particles the team gathered after two other rainstorms in Lamont as well as those emitted from a garden in Richland, Wash., after it was watered by sprinkler.
“The idea of rain producing aerosols, much less solid ones, just hasn’t been on anyone’s radar,” said Gilles. “Rain cleans the atmosphere; it hadn’t occurred to me to think of rain as a mechanism to produce solid particles from soil.”
Light absorbers…light deflectors
The particles, sometimes called “brown carbon,” have the potential to absorb sunlight, perhaps heating the planet. And the particles can serve as nuclei controlling processes related to cloud formation, creating more clouds or making existing clouds brighter — actions which would cause sunlight to be reflected.
Finding a new source of the airborne particles, known as aerosols, is important for scientists seeking to understand the planet’s climate.
“This is a new mechanism for bringing carbon from the soil into the air. These particles have a unique set of physical and chemical properties and they may have a substantial effect on the Earth’s climate,” said Laskin, who led the study.
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