Air Temperatures – The following high temperatures (F) were recorded across the state of Hawaii Monday…along with the low temperatures Monday:

79 – 64  Lihue, Kauai
68  Honolulu, Oahu
mm mm  Molokai
81 –
58  Kahului AP, Maui
67  Kailua Kona
64  Hilo AP, Hawaii

Here are the latest 24-hour precipitation totals (inches) for each of the islands Monday evening:

0.01  Puu Lua, Kauai
0.01  Kahana

0.00  Molokai
0.00  Lanai
0.00  Kahoolawe
0.00  Maui
0.17  Saddle Quarry, Big Island

The following numbers represent the strongest wind gusts (mph) Monday evening:

24  Mana, Kauai
25  Oahu Forest NWR, Oahu
24  Molokai
27  Lanai
28  Kahoolawe
29  Maalaea Bay, Maui

31  Kealakomo, Big Island

Hawaii’s MountainsHere’s a link to the live webcam on the summit of our tallest mountain Mauna Kea (nearly 13,800 feet high) on the Big Island of Hawaii. Here’s the webcam for the Haleakala Crater on Maui. These webcams are available during the daylight hours here in the islands, and at night whenever there’s a big moon shining down. Also, at night you will be able to see the stars — and the sunrise and sunset too — depending upon weather conditions.

Aloha Paragraphs
High pressure over the islands and east-northeast…cold front northwest
A mostly clear to partly cloudy Monday night
A few clouds…more northeast of the islands
A few showers – Looping image


~~~ Hawaii Weather Narrative ~~~

Small Craft Advisory…
all coasts and channels except around Kauai, windward Oahu, and windward Big Island

High Surf Advisory…
north and west shores Niihau, Kauai, Oahu and Molokai/ north shores of Maui

Gale Watch…Alenuihaha and Pailolo Channels, Big Island southeast waters, and Maalaea Bay (starts Wednesday morning)


Broad Brush Overview: Light to locally moderate trade winds are returning, after several days of lighter than normal breezes, with generally dry weather continuing into Tuesday. The trades will gradually strengthen through the first half of this new work week, becoming stronger and gusty by Wednesday. Windward and mountain showers will gradually increase as the trade winds increase in strength…although leeward areas should remain mostly dry.

Details: The weak surface ridge will continue to migrate slowly northward…with the trade winds gradually increasing in strength. Rainfall will remain limited, especially over the western and central islands, as scant moisture and a low and strong inversion persists…with the deep ridge continuing to strengthen over the state. As the trades become established, clouds and light passing showers will become focused over the windward and mountain sides.

A cold front will pass well north of the state Tuesday, with a much stronger high building behind it. The front will not have any impact on our weather, although the high will cause the trades to increase significantly Wednesday.  Wind Advisories over the islands, with gales over the windier waters are possible. The GFS model shows land and sea breezes by the weekend, as a trough develops to our west, causing the wind flow to veer to the southeast. This would have the Big Island blocking winds from the smaller islands, and bringing volcanic haze northwest. On the other hand, some models show a persisting trade wind pattern…stay tuned.

Looking Further Ahead: Strengthening trades would normally bring increased showers to the windward sides, although continued deep layered ridging aloft, and below normal moisture levels, should keep showers limited in strength and coverage through Wednesday. A weak upper trough forecast to develop to our west, along with a modest increase of low level moisture should improve our rain chances, especially for windward areas later in the week. Rain coverage for the weekend will depend on whether we see the trade winds sticking around, a land and sea breeze pattern returning…or a combination of the two…stay tuned. 

Here’s a wind profile of the Pacific Ocean – Closer view of the islands / Here’s the vog forecast animation / Here’s the latest weather map

Marine environment details: The largest northwest swell of the winter season peaked early Sunday, and will continue to slowly lower through the first half of this new week. Warning level surf associated with this swell will likely hold for exposed north and west facing shores of the smaller islands. The warning on the Big Island has been replaced with an advisory, due to a combination of the lowering trend and surf reports from the Big Island. This transition is expected for the smaller islands tonight through Tuesday.

Despite some forecast uncertainty, due to differences shown between model cycles over the past couple of days, a reinforcing swell out of the northwest Wednesday remains a possibility, which would be short-lived with a quick downward trend expected Thursday.

Surf along east facing shores will become rough late Wednesday through Thursday, likely bringing advisory level conditions for east facing beaches.
Lowering surf on the north and west shores…along with strengthening trade winds

World-wide Tropical Cyclone activity

>>> Here’s the latest PDC Weather Wall Presentation, covering Tropical Cyclone 06S (Berguitta) in the South Indian Ocean

>>> Atlantic Ocean:

>>> Caribbean Sea:

>>> Gulf of Mexico:

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

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

Here’s a link to the Central Pacific Hurricane Center (CPHC)

>>> Northwest Pacific Ocean: No active tropical cyclones

>>> South Pacific Ocean: No active tropical cyclones

North and South Indian Oceans / Arabian Sea:

Here’s a link to the Joint Typhoon Warning Center (JTWC)

Jet Stream Changes Since 1960s Linked to More Extreme Weather
– Increased fluctuations in the path of the North Atlantic jet stream since the 1960s coincide with more extreme weather events in Europe such as heat waves, droughts, wildfires and flooding, reports a University of Arizona-led team.

[Jet streams are like rivers of wind high above in the atmosphere. These slim strips of strong winds have a huge influence on climate, as they can push air masses around and affect weather patterns]

The research is the first reconstruction of historical changes in the North Atlantic jet stream prior to the 20th century. By studying tree rings from trees in the British Isles and the northeastern Mediterranean, the team teased out those regions’ late-summer weather going back almost 300 years — to 1725.

“We find that the position of the North Atlantic jet in summer has been a strong driver of climate extremes in Europe for the last 300 years,” said Valerie Trouet, an associate professor of dendrochronology at the UA Laboratory of Tree-Ring Research.

Having a 290-year record of the position of the jet stream let Trouet and her colleagues determine that swings between northern and southern positions of the jet became more frequent in the second half of the 20th century, she said.

“Since 1960 we get more years when the jet is in an extreme position,” Trouet said, adding that the increase is unprecedented.

When the North Atlantic jet is in the extreme northern position, the British Isles and western Europe have a summer heat wave while southeastern Europe has heavy rains and flooding, she said.

When the jet is in the extreme southern position, the situation flips: Western Europe has heavy rains and flooding while southeastern Europe has extreme high temperatures, drought and wildfires.

‘It’s a Double Whammy’

“Heat waves, droughts and floods affect people,” Trouet said. “The heat waves and drought that are related to such jet stream extremes happen on top of already increasing temperatures and global warming — it’s a double whammy.”

Extreme summer weather events in the American Midwest are also associated with extreme northward or southward movements of the jet stream, the authors write.

“We studied the summer position of the North Atlantic jet. What we’re experiencing now in North America is part of the same jet stream system,” Trouet said.

This winter’s extreme cold and snow in the North American Northeast and extreme warmth and dryness in California and the American Southwest are related to the winter position of the North Pacific jet, she said.

The paper, “Recent enhanced high-summer North Atlantic jet variability emerges from three-century context,” by Trouet and her co-authors Flurin Babst of the Swiss Federal Research Institute WSL in Birmensdorf and Matthew Meko of the UA, appeared in Nature Communications. The U.S. National Science Foundation and the Swiss National Science Foundation funded the research.

“I remember quite vividly when I got the idea,” Trouet said. “I was sitting in my mom’s house in Belgium.”

While visiting her family in Belgium during the very rainy summer of 2012, Trouet looked at the newspaper weather map that showed heavy rain in northwestern Europe and extreme heat and drought in the northeastern Mediterranean.

“I had seen the exact same map in my tree-ring data,” she said. The tree rings showed that hot temperatures in the Mediterranean occurred the same years that it was cool in the British Isles — and vice versa.

The part of an annual tree ring that forms in the latter part of the growing season is called latewood. The density of the latewood in a particular tree ring reflects the August temperature that year.

Jet Stream’s Historical Position

Other investigators had measured the annual latewood density for trees from the British Isles and the northeastern Mediterranean for rings formed from 1978 back to 1725.

Because August temperatures in those two regions reflect the summer position of the North Atlantic jet stream, Trouet and her colleagues used those tree-ring readings to determine the historical position of the jet stream from 1725 to 1978. For the position of the jet stream from 1979 to 2015, the researchers relied on data from meteorological observations.

“There’s a debate about whether the increased variability of the jet stream is linked to man-made global warming and the faster warming of the Arctic compared to the tropics,” Trouet said.

“Part of the reason for the debate is that the data sets used to study this are quite short — 1979 to present. If you want to see if this variability is unprecedented, you need to go farther back in time — and that’s where our study comes in.”

With the discovery of much older trees in the Balkans and in the British Isles, Trouet hopes to reconstruct the path of the North Atlantic jet stream as much as 1,000 years into the past. She is also interested in reconstructing the path of the North Pacific jet stream, which influences the climate and weather over North America.