Hawaiian Islands Weather Details & Aloha Paragraphs / July 21-22, 2017

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

87 – 75  Lihue, Kauai
88 – 76  Honolulu, Oahu
90 – 78  Molokai
87 – 74  Kahului AP, Maui
86 – 75  Kailua Kona
83 – 71  Hilo AP, Hawaii

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

1.01  Mount Waialeale, Kauai
0.10  Tunnel RG, Oahu
0.12  Molokai
0.00  Lanai
0.25  Kahoolawe
1.82  West Wailuaiki, Maui
1.40  Kawainui Stream, Big Island

The following numbers represent the strongest wind gusts (mph) as of Friday evening:

31  Lihue, Kauai
32  Oahu Forest NWR, Oahu
32  Molokai
27  Lanai
31  Kahoolawe
29  Kahului AP, Maui
25  South Point, Big Island

Hawaii’s Mountains – Here’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. This webcam is 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

Tropical Storm Fernanda and Tropical Storm Greg, and Tropical Depression 09E to the east 

 
Fernanda will weaken…as strong southwesterly wind shear aloft tears it apart

Fernanda will weaken further to a remnant low tonight

 

Fernanda’s cloud swirl to the right of the islands…will run out of steam

Clouds out ahead of Fernanda…move into the islands from the east

Showers mostly windward and mountains…and offshore
Looping radar image

Small Craft Advisory…windiest coasts and channel around Maui County and the Big Island

High Surf Advisory…east shores of Kauai, Oahu, Molokai, Maui and the Big Island

Special Weather Statement…Coastal Flooding Possible:

Coastal flooding associated with king tides will be a possibility during the next few days. The greatest potential for coastal flooding impacts will be during the mid to late afternoon hours through Monday, when the highest tides are expected.

Note that east swell energy, which was generated by Tropical Cyclone Fernanda, will produce elevated surf along east facing shores through this weekend. This will likely cause greater wave run-up along some exposed windward coastlines, especially during high tide.

Impacts of the king tides may include flooding of beaches that are normally dry, salt water inundation of typically vulnerable low-lying roads, docks, boat ramps and other coastal infrastructure. The potential threat for coastal flooding will eventually be reduced early next week as the peak daily tides diminish.

 

~~~ Hawaii Weather Narrative ~~~

 

Broad Brush Overview: Moderately strong high pressure systems are located far to the northwest, north and northeast, with a connecting ridge of high pressure between these cells…keeping the trades going into the weekend. The combination of moist, tropical air overspreading the islands, and a weak upper trough of low pressure, will enhance trade wind showers. Tropical Depression Fernanda is forecast to weaken this weekend, as it approaches, and should only be a remnant low or trough by the time it’s closer Monday. The remnants of Fernanda will bring lighter winds and uncomfortable humidity, along with a chance for heavy showers locally later Sunday into Monday. More settled conditions with lower humidity is expected by later Tuesday into next Wednesday…as trade winds return.

Details: As Fernanda approaches, it will gradually become more humid and uncomfortable, especially by Sunday night into Tuesday morning. There’s the possibility of locally heavy showers developing over leeward Maui and the Big Island Sunday and Monday afternoons. There’s always the chance that we may get flooding rainfall from TC Fernanda’s remnants…although the models seem to suggest that localized downpours will be about it, time will tell. The forecast details will need to be adjusted as this system gets into closer range. Otherwise, we can look for rainfall to increase later this weekend into early next week…at least locally.

Looking Further Ahead: Tropical Storm Greg is forecast by National Hurricane Center (NHC) to continue on a generally westward to west-northwestward track through the next several days. All models keep the system east of Hawaii through next Friday.

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: Locally strong trade winds will continue to produce Small Craft Advisory (SCA) conditions through early Saturday morning for the typically windy waters adjacent to the islands of Maui County and the Big Island.

The latest forecast for Tropical Storm Fernanda continues to indicate the tropical cyclone will weaken to a remnant low, that will move to a position northeast of the Big Island Sunday afternoon. As this area of lower pressure approaches, look for the trade winds to weaken this weekend. The flow will likely become much lighter early next week, as the remnants of Fernanda pass by to the north of the islands late Sunday into early Tuesday.

A High Surf Advisory remains in effect for the east facing shores of the Big Island and Maui through early Saturday morning, due to a east swell from when Fernanda was a major hurricane in the eastern Pacific. Wave model guidance indicates reinforcing east swell energy from Fernanda arriving along the east facing shores later today and tonight. As this reinforcing swell continues to spread westward to the remainder of the smaller islands, a High Surf Advisory will also likely be needed for east facing shores of Molokai, Oahu and Kauai starting Saturday or Sunday.

The largest high tides of the month (king tides) will occur each afternoon during the next few days. Note that these abnormally high tides, combined with wave run up due to the east swells produced by Fernanda, may result in coastal flooding in some areas, especially today into Monday.

Elsewhere, no significant swells are expected. Small south swells will continue to produce small surf along south facing shores into next week.

Larger surf east shores…generated by Fernanda

>>> Southern California Weather Brief: Expect night through morning low clouds to persist across most coastal areas and possibly into portions of coastal valleys at times. High pressure will continue to dominate the weather pattern with slightly higher than normal temperatures for inland areas through Saturday. A weak upper trough will move close to the forecast area allowing some modest cooling through early next week with the possibility of monsoonal moisture affecting the local mountains and deserts. A warming trend expected by mid-week.

Mostly clear inland, low clouds offshore…extending inland locally

 

>>> San Francisco Bay area weather brief: A building ridge of high pressure will lead to warmer temperatures this weekend…cooling is then expected early next week.

Low clouds mostly offshore

World-wide tropical cyclone activity

>>> Atlantic Ocean: No active tropical cyclone

No tropical cyclones are expected during the next 5-days

>>> Caribbean: No active tropical cyclone

No tropical cyclones are expected during the next 5-days

>>> Gulf of Mexico: No active tropical cyclones

No tropical cyclones are expected during the next 5-days

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:

Tropical Storm Greg remains active, here’s a graphical track map, a satellite image…and what the computer models are showing

Tropical Depression 09E remains active, here’s a graphical track map, a satellite image…and what the computer models are showing

1.) A low pressure system is centered about 600 miles south-southwest of the southern tip of the Baja California peninsula. Showers and thunderstorms have increased overnight and, if this trend continues, advisories will be initiated on a tropical depression later this morning. Environmental conditions are forecast to be conducive for development during the next couple of days while the system moves generally westward at around 10 mph.

This disturbance is being referred to as Invest 99E, here’s a satellite image…and what the computer models are showing

* Formation chance through 48 hours…high…90 percent
* Formation chance through 5 days…high…90 percent

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:

Tropical Storm Fernanda remains active, here’s the track map, a satellite image…and what the computer models are showing.

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

>>> Northwest Pacific Ocean:

Tropical Storm 07W (Noru) is active, here’s a graphical track map, a satellite image…and what the computer models are showing.

Tropical Depression 08W is active, here’s a graphical track map, a satellite image…and what the computer models are showing.

Tropical Storm 09W (Kulap) is active, here’s a graphical track map, a satellite image…and what the computer models are showing.

Tropical Storm 10W (Roke) is active, here’s a graphical track map, a satellite image…and what the computer models are showing.