Air Temperatures – The following maximum temperatures (F) were recorded across the state of Hawaii Thursday…along with the low temperatures Thursday:
81 – 73 Lihue, Kauai
81 – 73 Honolulu, Oahu
82 – 73 Molokai AP
87 – 68 Kahului AP, Maui
84 – 75 Kailua Kona
84 – 70 Hilo AP, Hawaii
Here are the latest 24-hour precipitation totals (inches) for each of the islands…as of Thursday evening:
1.88 Mohihi Crossing, Kauai
6.35 Poamoho RG 1, Oahu
0.59 Puu Alii, Molokai
0.71 Lanai
0.04 Kahoolawe
1.91 Puu Kukui, Maui
0.51 Lower Kahuku, Big Island
The following numbers represent the strongest wind gusts (mph)…as of Thursday evening:
20 Port Allen, Kauai
18 Kii, Oahu
25 Molokai
21 Lanai
30 Kahoolawe
28 Kapalua, Maui
27 Upolu AP, 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.
Aloha Paragraphs
There’s low pressure systems far north of the state…
with trailing cold fronts
Scattered low clouds in the area of the islands…with
the whiter and brighter clouds at higher levels
Clear to partly cloudy, high cirrus over the Big Island and
Maui County…and north of Kauai
Showers locally…heavy over some parts of Oahu
Looping radar image
2016 Central Pacific Hurricane Season Outlook:
4-7 Tropical Cyclones between June 1 and November 30
(average number of TC’s per year: 4-5)
2015 had 15 Tropical Cyclones…the old record was 11 in
1992 and 1994
Least active years, with 0 systems…1977, 1969, 1964 and 1960
~~~ Hawaii Weather Narrative ~~~
Flash Flood Warning…Princeville, Kilauea, Haena, Wainiha,
Moloaa, Hanalei, Wailua Homesteads, and Lalihiwai – until 630am
We’ll find unusually light winds across the islands through the rest of this week…into the first several days of next week. Here’s the latest weather map, showing moderately strong high pressure systems to the north and far northeast. At the same time, there’s the tail-end of a stationary cold front/trough to the north of the islands. This surface trough of low pressure will remain in our vicinity through the rest of the week. The winds are expected to arrive from the southeast in general through Friday. The models then show the winds becoming light and variable during the weekend, keeping rather warm and sultry conditions over the islands during the days. The light southeasterly breezes are already bringing volcanic haze over the smaller islands…at least in places. Look for the return of light to moderately strong trade winds around the middle of next week.
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
Our local atmosphere is gradually becoming more stable…and less shower prone now. Whatever precipitation that falls over the next day or so, will focus along the windward sides…and also over the leeward sides during the afternoon hours. As the winds remain light during the weekend, we’ll see most of our showers popping-up over the leeward slopes during the afternoon hours. As the trade winds become established around the middle of next week, in the wake of a very late season frontal cloud band, most showers will gravitate towards the windward coasts and slopes then. If the winds remain lighter than expected, we’ll continue to find some afternoon showers falling along our leeward slopes during the afternoon hours as well.
Marine environment details: Gentle winds and moderate swells are expected through next week, so no small craft advisory conditions are expected.
A moderate southwest swell from the Tasman sea is expected to peak Friday, then decline during the weekend. Since there are so many islands along the path of the swell, surf is likely to be inconsistent. A small northwest swell arriving Sunday will peak Monday well below the advisory threshold.
Anini Beach…Kauai
Here on Maui – Early Thursday morning is dawning mostly clear to partly cloudy. Here at my place in upcountry Kula, it’s calm and clear…with an air temperature of 52.9F degrees at 535am. Meanwhile, at about the same time, the Kahului AP was reporting clear skies, with an air temperature of 66 degrees, 68 at Maalaea Bay, 72 degree out in Hana…and the summit of the Haleakala Crater was 41 degrees. It’s a beautiful morning! / Now at 1130am, the clear skies earlier in the morning, are giving way to rather quickly increasing clouds.
– Early afternoon, with clouds gathering fast, although it looks like they are packin’ up over and around the mountains for the most part. Here at my weather tower in Kula, at 135pm, I’m seeing the first little tiny drops starting to fall. / Now at 230pm, it’s way cloudy here in Kula, and light rain has begun to fall. I can still see down into the central valley, and it looks partly sunny down there. The north shore still looks mostly sunny as well, so these showers are mostly occurring in the upcountry interiors at the moment.
– Early evening on this Thursday, and the “trade winds should be blowing” at least moderately strong…if not stronger. This unusual period of lighter than normal winds isn’t through with us by a long shot! They are forecast to continue through Monday or Tuesday…we’ll see. The latest computer models are now even suggesting that they may fade away again towards the end of next week…wow! At any rate, we have partly to mostly cloudy skies over us now, and above that, there are lots of high level cirrus clouds. These may light up a nice color of pink or orange at sunset. If they’re still around at sunrise on Friday, we may get some more color then.
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
1.) Shower activity associated with the low pressure area located between Bermuda and the Bahamas continues to show signs of organization, and the circulation of the low has become a little better defined overnight. Environmental conditions are generally conducive for a tropical or subtropical cyclone to form later today or Saturday while this system moves west-northwestward to northwestward toward the southeastern United States coast. All interests along the southeast coast from Georgia through North Carolina should monitor the progress of this low. An Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate the low this afternoon.
This area of disturbed weather, being referred to as Invest 91L will likely bring heavy flooding rainfall with it…as it gets closer to the southeast coast.
Here’s a satellite image of this area…along with what some of the computer models are showing
* Formation chance through 48 hours…high…90 percent
* Formation chance through 5 days…high…90 percent
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: 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: 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: Spring comes sooner to urban heat islands…with potential consequences for wildlife – With spring now fully sprung, a new study by University of Wisconsin–Madison researchers shows that buds burst earlier in dense urban areas than in their suburban and rural surroundings. This may be music to urban gardeners’ ears, but that tune could be alarming to some native and migratory birds and bugs.
Urban-dwelling plants around the globe typically get a head start on the growing season compared to their rural counterparts because of the urban heat island effect, the phenomenon in which cities tend to be warmer than non-urban areas due to their plethora of built surfaces — made of concrete, asphalt and more — and scarcity of vegetation.
But according to the study, published this week in Environmental Research Letters, the urban heat island doesn’t lengthen the growing season uniformly across a city. Within the study site (Madison, Wisconsin) the researchers found that while the growing season lasted up to a week longer in the city’s densest areas, its parks subdued the warming effect and thus helped to normalize the growing season length.
“With a better understanding of the impacts of urbanization on vegetation, we can create more sustainable cities that behave more similarly to the natural areas they have replaced,” says lead author Samuel Zipper, who recently completed his Ph.D. in freshwater and marine sciences and is part of the UW–Madison Water Sustainability and Climate Project, a program funded by the National Science Foundation. “Every little bit of greenness counts within a city.”
The spring green-up underpins many important natural processes, like the budding of flowers and release of pollen. Throwing off the timing of this cycle can have cascading effects on urban ecosystems that may be harmful to birds, butterflies and other wildlife in search of food and habitat. The study shows that urban parks can provide them “cool island” refuges, with natural conditions to which they are better accustomed.
The study is the first of its kind to examine how variations in urban development impact the length of plant growing seasons at fine scales within a city. The research team relied on a uniquely dense network of temperature sensors scattered in and around Madison to get such a detailed look.
The sensor data revealed that unless researchers are accounting for the types of plants they are observing, satellite data may not be the best way to tease out the temperature-based effects of urbanization on plants. The satellite-based method is commonly used to assess the start and end of growing seasons, but it may be sensing changes unrelated to the urban heat island, the team’s methods suggest.
For instance, grassy lawns in the suburbs greened up more quickly than urban trees despite higher air temperatures in the city. This is because once the snow melts, grass typically greens up sooner than trees, Zipper says.
“The degree to which the potential growing season gets longer is related to urban density, but the actual growing season depends on what is growing on the ground,” he explains.
The study is a step toward better understanding how urban development can impact not just growing seasons but also other natural cycles, like those of water and carbon. It could also help make cities more resilient to climate change.
The urban heat island effect is expected to increase as the climate warms, Zipper says, adding, “The fine-scale decisions we make in cities will be important.”
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