Pacific Disaster Center Fostering Disaster Resilient Communities  

Providing Weather and Hazard Related News

Weather Wall

 

 

Nov
16
2011

Hawaii Weather Overview


Hawaiian Weather Synopsis: 
The computer forecast models have been right on with their forecasts of an upper level low pressure system…moving into the area west of Kauai. As this satellite image shows, there are lots and lots of clouds associated with this trough, and its associated upper level low pressure cell.  By the looks of things, we won’t be out from under this rather impressive canopy of multi-layered clouds…any time soon. Despite the presence of this upper and middle level moisture in the atmosphere, not many showers are falling yet, at least not over the islands yet. The current thought is that showers will likely increase some along with the expected strengthening of trade wind speeds during the second half of this work week, and perhaps remain a bit more than normally active into the weekend as well.

The big question is just how much influence this upper low pressure will enhance showers that are around through the next several days. The closer that the upper low gets, along with its destabilizing cold air, will ultimately determine just how wet our weather becomes. As this looping radar image shows, there are some light to moderately heavy showers over the ocean to the south and southwest of central islands. The bulk of these seem to be headed towards Oahu at the time of this writing. The period with the best dynamics for heavier showers, or even a thunderstorm cell to form near Kauai or Oahu, would be through tonight into early Thursday. Maui County and the Big Island should be out of range for the most generous shower activity.

Looking ahead, it appears that the trade winds will continue, and increase in strength going into the weekend. We may see small craft  wind advisories go up over those windiest coasts and channels by Friday through Sunday. There may be a brief slow down in the wind speeds Monday into early Tuesday of next week, before a new high pressure system takes over duty, and our trade wind speeds accelerate again for several days, probably into the Thanksgiving holiday. Speaking of which, after consulting with the latest computer forecast models, there aren’t any rain bearing cold fronts on the horizon until after that major holiday…at least. It is the time of year when weather begins to change more quickly, so we’ll have to keep an eye out for any unscheduled changes in the current game plan.

 

PDC Global Hazards Atlas centered on the central Pacific Ocean near Hawaii is displaying precipitation accumulation over the last three hours

Click on the following link for the latest National Weather Service advisories and warnings: Wind/Surf/Flood related advisories or warnings

Broad Overview of Hawaii’s Weather

As this weather map shows, we find a 1029 millibar high pressure system located far to the northeast of the Hawaiian Islands Wednesday afternoon. This high pressure cell has an elongated ridge extending from its western flank, which continues into the area well north and northeast of the state. At the same time, there’s a 1016 millibar low pressure system parked to the north-northwest of Hawaii. There’s a cold front that is associated with this low pressure center, which is helping to limit the strength of our local trade winds…at least for the moment. Our trade winds will build in strength  tomorrow into Friday, which will remain on the stronger and gust into next week.

The following numbers represent the strongest wind gusts (mph), along with directions early Wednesday afternoon:

15                 Port Allen, Kauai – E
17                 Kahuku, Oahu – ENE
00                 Molokai – SW
16                 Kahoolawe – ESE
14                 Lipoa, Maui- ESE
08                 Lanai – WNW
27                 Upolu Point, Big Island – NE

We can use the following links to see what’s going on in our area of the north central Pacific Ocean early Wednesday afternoon. Looking at this NOAA satellite picture we can’t see any lower level clouds, due to the vast amount of cloudiness being carried overhead from the west and southwest. We can use this looping satellite image to see a counterclockwise rotating low pressure system well west of Kauai. This low is pumping considerable amounts of high and middle level clouds over our island chain. Checking out this looping radar image we see  showers falling locally over the ocean, some of which seem to be approaching Oahu from the south and southwest. It looks like there are some moderately heavy showers in this mix, although they hadn’t reached land yet.

Here are the 24-hour precipitation totals (inches) for each of the islands as of late Wednesday morning:

0.09               Mount Waialeale, Kauai
0.01               Oahu Forest NWR, Oahu
0.00               Molokai
0.00               Lanai
0.00               Kahoolawe
0.00               Kahakuloa, Maui
0.12               Mountain View, Big Island

Here is the latest NWS rainfall forecast

Here are the latest available satellite images:

Hawaii Infrared satellite image
Animated Satellite image of Hawaii region
Latest satellite image – Close-in visible satellite view
Latest radar image – Looping

SURF OUTLOOK:   Small to very small surf through Saturday, then somewhat larger Sunday and Monday

North shores –   Small surf until later this weekend from the northwest direction

West shores –    Very small surf through Sunday, locally flat…then a bump from the northwest Monday

South shores –   Very small surf through the rest of the week into next week…locally flat

East shores –   Small surf gradually rising along with the stronger trade winds Friday into next week

NOAA animated wave model