Trade winds will remain strong and gusty, reaching 40 to 50 mph in those windiest areas on the eastern islands, continuing through the rest of this week, passing windward showers at times…a few spreading over into the leeward sides
Hawaiian Weather Synopsis: The extra strong and gusty trade winds continue to buffet the Hawaiian Islands on this last day of autumn 2011. High pressure to the northeast, and a low pressure trough to the south and southeast of the Big Island are teaming up to keep this blustery reality over us. There’s a chance that these winds will diminish a little Thursday and Friday, although not so much that most folks will even notice. The computer models show the trade winds continuing on through the weekend, and right into early next week too.
Meanwhile, we have small craft wind advisory flags up across our entire marine environment, keeping very choppy and rough ocean conditions in place from the north shore of Kauai…right down to South Point on the Big Island. All this wind has triggered a high surf advisory too, with larger than normal waves breaking along our eastern beaches. At the same time, we have unusual gale warnings in force across the channels between Molokai and Maui, and the Alenuihaha Channel between Maui and the Big Island. This very strong trade wind episode isn’t just active near sea level, but is deep enough to be causing strong winds atop the Haleakala Crater on Maui…where a wind advisory is now in effect.
As all this wind is happening, we have also had localized heavy rains here and there, mostly over Maui and the Big Island…closest to the atmospheric destabilizing upper level low pressure system near the Big Island.The largest rainfall figure at the time of this writing was a very impressive 8.35″ atop the west Maui Mountains on Maui. The mountains on Oahu, and in places on the Big Island have been wet too, with the other islands finding showers along their windward sides for the most part.
Looking ahead a few days towards the Christmas holiday weekend, there’s still a bit of a question about which way it will go. The models the last several days have called for drier weather Saturday and Sunday, although the most recent ones aren’t quite as positive about that drying out, with the chance of the showers keeping the windward sides soggy through the weekend. It might be wise to give those models another couple of runs, before we try and be too confident about what the Christmas Eve and Christmas Day weather outlook might be just yet.
Click on the following link for the latest National Weather Service advisories and warnings: Wind/Surf/Flood related advisories or warnings
Details of Hawaii’s Weather – Wind/Precipitation/Surf
As this weather map shows…we have several high pressure systems located far to the northeast of the Hawaiian Islands Wednesday afternoon. The southern most high pressure system has a ridge that runs southwest from its center, into the area north and northwest of the state…actually all the way into the western Pacific Ocean. At the same time, we find a surface trough of low pressure to the south-southeast of the Big Island, which is helping to enhance the strength of our local trade wind speeds. These trade winds are expected to continue through the rest of this week…into the first part of next week.
The following numbers represent the strongest wind gusts (mph), along with directions early Wednesday afternoon:
30 Lihue, Kauai – NE
36 Waianae Valley, Oahu – ESE
37 Molokai – NE
43 Kahoolawe – E
40 Kaupo Gap, Maui – NE
50 Lanai – NE
40 PTA Kipuka Alala, Big Island – NE
We can use the following links to see what’s going on in our area of the north central Pacific Ocean Wednesday afternoon.Looking at this NOAA satellite picture we find that the high and middle level clouds are located to the southwest through southeast and east to the northeast of the islands at this hour. We can use this looping satellite image to see lots of towering cumulus and thunderstorms developing to the southwest and east over the ocean, associated with a counter-clockwise rotating upper level low pressure system…to the south of the islands. Checking out this looping radar image we see showers over the ocean, most of which are light to moderately heavy, although some are heavier coming in over the islands…most notably to the southeast of the Big Island.
Here are the 24-hour precipitation totals (inches) for each of the islands as of late Wednesday morning:
1.70 Mount Waialeale, Kauai
2.44 Oahu Forest NWR, Oahu
8.35 Puu Kukui, Maui
1.95 Waiakea Uka, Big Island
Here is the latest NWS rainfall forecast
Here are the latest available satellite images:
SURF OUTLOOK: The north shores will gradually Wednesday into Thursday. The west sides will be gradually through Thursday as well. Surf along the east shores will remain rough and choppy both days…as the strong trade winds continue. South shores will be very small through the next two days.
North shores – Small to lower medium northwest swells will keep waves breaking through most of this week…choppy ocean conditions continuing.
West shores – Generally small northwest swells will keep these beaches active, although smaller than the north shores as usual.
South shores – Surf will remain very small on these leeward shores
East shores – Wind swell continues…rough and choppy