Air Temperatures – The following maximum temperatures (F) were recorded across the state of Hawaii Tuesday…along with the minimums Tuesday:
82 – 65 Lihue, Kauai
83 – 70 Honolulu, Oahu
81 – 69 Molokai AP
86 – 72 Kahului AP, Maui
84 – 69 Kailua Kona
86 – 66 Hilo AP, Hawaii
Here are the latest 24-hour precipitation totals (inches) for each of the islands, as of Tuesday evening:
0.48 Kilohana, Kauai
0.13 Poamoho, Oahu
0.12 Puu Alii, Molokai
0.00 Lanai
0.07 Kahoolawe
0.21 Kula 1, Maui
0.08 Laupahoehoe, Big Island
The following numbers represent the strongest wind gusts (mph)…as of Tuesday evening:
25 Port Allen, Kauai – WNW
27 Kii, Oahu – W
22 Molokai – WSW
20 Lanai – SW
20 Kahoolawe – SW
29 Kahului AP, Maui – NNE
30 South Point, Big Island – SW
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 large storm low pressure system far north…along with a
fragmenting cold front moving through the state
A narrow cold front is breaking up, after moving over Kauai and
Oahu…slowing down around Maui County
Northeast to southwest cloud band over Maui County
Just a few showers falling along a feeble cold front
looping radar image
High Wind Warning…summits on the Big Island of Hawaii –
45-75 with 85 mph gusts
Small Craft Advisory…windiest coasts and channels most areas
around the state
High Surf Warning…north and west facing shores of Kauai, Oahu,
Molokai, and north shore of Maui
High Surf Advisory…west facing shore of the Big Island
~~~ Hawaii Weather Narrative ~~~
South to southwest Kona winds ahead of a weak cold front…turning light Wednesday and Thursday. Here’s the latest weather map, showing the Hawaiian Islands, and the rest of the North Pacific Ocean. We find high pressure systems far to the northeast and west of Hawaii. Looking further out to sea, we see storm and gale low pressure systems far to the north. Finally, we see a weakening cold front moving through the islands from the northwest. Our local winds are locally quite gusty from the southwest, ahead of this slow moving cold front. We’ll likely see another short period of light winds, in the wake of the frontal passage (fropa). We’ll end up with light to moderately strong trade winds Friday through the weekend…into early 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
Marine environment details: The incoming northwest swell is expected to build tonight, bringing warning level surf to north and west facing shores of the smaller islands, and the west facing shores of the Big Island. The swell will also bring seas in excess of 10 feet for most of the coastal waters, so a small craft advisory has also been issued. The swell is expected to peak Wednesday and then slowly subside through the end of the week. A small to moderate south swell will peak Wednesday and diminish Thursday.
A cold front passing down through the state…will bring a few showers over the eastern islands. This cold front arrived over Kauai early Tuesday morning, and has finished its journey through Oahu, and is now over Maui County. It’s likely to stretch down over the Big Island into Wednesday morning…where it will dissipate. This frontal boundary has brought a modest period of showers to the island chain, although having little upper level support…showers haven’t been very impressive. There was a pre-frontal band of clouds out ahead of the front itself, which brought showers overnight into Tuesday morning as well. The outlook shows relatively drier weather returning during the second half of this week, with fairly routine windward showers at times into the weekend. The leeward sides should have nice weather during this extended forecast period, with few showers if any…and lots of daytime sunshine.
Rising large surf along the north
and west shores
Here in Maui County…It’s cloudy and foggy with passing showers in upcountry Kula early this morning, with the air temperature 59.7F degrees. The temperature at nearly the same time was 72 degrees down in Kahului under partly cloudy skies, 64 out in Hana, and 41 atop the Haleakala summit. Meanwhile, Kahoolawe was 75 degrees, 69 at Lanai City with cloudy skies, with 70 at the Molokai airport…with clear skies. / Now at 645am, the clouds are breaking up, the rain has stopped, and the gusty winds from earlier are calming down. I still can’t see what’s happening over the rest of the island just yet, although I imagine its a similar situation.
– Tuesday afternoon, I can see lots of clear blue skies, along with increasing clouds to the southwest. These cumulus clouds are part of the weakening cold front pushing down through the state. It has begun to fall apart, and to be true, it wasn’t all that together…before it even arrived over Kauai, heading southeast. Radar shows some evidence of showers, falling mostly over the ocean, more or less associated with this frontal boundary. It looks like this morning’s pre-frontal cloud band, which moved over parts of Maui County before sunrise, was by far the more pronounced rainfall producer. Meanwhile, the gust kona winds (southwest) continue to blow ahead of this front.
– Tuesday evening, we’re seeing increasing clouds associated with a weak cold front. Showers from these clouds are minor, although we may see some falling here and there over Maui County…before it crawls down towards the Big Island overnight. The gusty southwest winds continued all day, although should calm down tonight, as we get on the back side of this frontal boundary.
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:
Tropical Cyclone 17S is dissipating in the South Indian Ocean, located approximately 1270 NM south-southeast of Diego Garcia. Winds are 35 knots sustained, with gusts to 45 mph. Here’s a satellite image, along with the JTWC graphical track map – Final Warning
Here’s a link to the Joint Typhoon Warning Center (JTWC)
Interesting: Ocean temperatures predict U.S. heat waves – The formation of a distinct pattern of sea surface temperatures in the middle of the North Pacific Ocean can predict an increased chance of summer heat waves in the eastern half of the U.S. up to 50 days in advance.
The pattern is a contrast of warmer-than-average water coming up against cooler-than-average seas. When it appears, the odds that extreme heat will strike during a particular week — or even on a particular day — can more than triple, depending on how well-formed the pattern is.
The findings were published today in the journal Nature Geoscience. The lead author is scientist Karen McKinnon of the National Center for Atmospheric Research (NCAR) in Boulder, Colorado.
“Summertime heat waves are among the deadliest weather events, and can have big effects on farming, energy use and other critical aspects of society,” said McKinnon. “If we can give city planners and farmers a heads-up that extreme heat is on the way, we might be able to avoid some of the worst consequences.”
In addition to McKinnon, the research team includes Andrew Rhines of the University of Washington, Martin Tingley of Pennsylvania State University and Peter Huybers of Harvard University.
“This intriguing result has enormous practical implications,” said Candace Major, program director in the National Science Foundation (NSF) Division of Ocean Sciences, which funded the research along with NSF’s Division of Atmospheric and Geospace Sciences. “The potential for predicting the risk of dangerous heat waves more than a month in advance is very exciting. With more time to prepare, communities have a greater chance of avoiding the serious economic and health consequences of weather extremes.”
A fingerprint on the ocean
For the study, the scientists divided the country into regions that tend to experience extreme heat at the same time. They then focused on the largest of the resulting blocks: a swath that stretches across much of the Midwest and up the East Coast, encompassing important agricultural areas and heavily populated cities.
The researchers looked for a relationship between global sea surface temperature anomalies — waters warmer or cooler than average — and extreme heat in the eastern half of the U.S.
A pattern popped out in the middle of the Pacific, above a point roughly 20 degrees north latitude. The scientists could find the particular configuration of ocean water temperatures, which they named the Pacific Extreme Pattern, not only when the eastern U.S. was already hot, but also in advance of that heat.
“Whatever mechanisms ultimately lead to the heat wave also leave a fingerprint of sea surface temperature anomalies behind,” McKinnon said.
Improving seasonal forecasts
To test how well that activity could predict future heat, the scientists used data collected from 1,613 weather stations across the eastern U.S. between 1982 and 2015, as well as daily sea surface temperatures from the same time period.
The researchers defined extreme heat in the eastern U.S. as a summer day when the temperature readings from the warmest 5 percent of weather stations in the region were at least 6.5 degrees Celsius (11.7 degrees Fahrenheit) hotter than average. They only examined extreme heat during that region’s 60 hottest days of the year: June 24 through Aug. 22.
The scientists “hindcasted” each year in the data set to see if they could retrospectively predict extreme heat events — or the lack of those events — during that year’s summer.
At 50 days out, they were able to predict an increase in the odds — from about one-in-six to about one-in-four — that a heat wave would strike somewhere in the eastern U.S. during a given week.
For a particularly well-formed pattern, at 30 days out or closer the scientists were able to predict that a heat wave would strike on a particular day at odds of better than one-in-two.
This new technique could improve existing seasonal forecasts, which do not focus on predicting daily extremes. Seasonal forecasts typically predict whether an entire summer is expected to be warmer than normal, normal, or cooler than normal.
For example, the seasonal forecast issued for the summer of 2012 predicted normal heat for the Northeast and Midwest. But the summer ended up being especially hot, thanks to three major heat waves that struck in late June, mid-July and late July.
When the research team used the Pacific Extreme Pattern to hindcast 2012, they were able to determine as early as mid-May increased odds of extremely hot days occurring in late June.
The hottest day of the summer of 2012, as measured by the technique used for this study, was June 29, when the warmest 5 percent of weather stations recorded temperatures that were 10.4 degrees Celsius (18.7 degrees Fahrenheit) above average.
“We found that we could go back as far as seven weeks and still predict an increase in the odds of future heat waves,” McKinnon said. “What’s exciting about this is the potential for long-range predictions of individual heat waves that give society far more notice than current forecasts.”
Looking ahead
Scientists don’t yet know why the fingerprint of sea surface temperatures in the Pacific predicts heat on the East Coast.
It could be that the sea surface temperatures themselves kick off weather patterns that cause the heat. Or it could be that they are both different results of the same phenomenon, but one does not cause the other.
To learn more about how the two are connected, McKinnon is working with colleagues at NCAR to use sophisticated computer models to try to tease apart what’s happening.
The study’s findings also point to the possibility that the Pacific Extreme Pattern, or a different oceanic fingerprint, could be used to forecast other weather events far in advance, including cooler-than-average days and extreme rainfall events.
“The results suggest that the state of the mid-latitude ocean may be a previously overlooked source of predictability for summer weather,” McKinnon said.
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