Record-setting wet weather coming to an end
We've seen downpours and even record setting events this winter, but that may be about to change.
HONOLULU - Record rainfall hits Hawaii again this week.
Several days this winter we've seen downpours and even record setting events, but that may be about to change.
When heavy rains came down on Oahu Tuesday, run off came pouring out of some storm drains and manholes, including one off School Street that flowed into a canal in Kalihi.
"The water level was pretty high, and the run off looked like a brown river. I guess it would be about a yard high, which is not really normal," said resident Aileen Kow.
in fact, the rain event was record setting for Honolulu, with more than 2 inches of rain falling in just 12 hours.
The deluge left some sections of Oahu underwater, flooding several streets in Kahala.
And turned Queen Street in Kakaako into the perfect place to paddle board.
Hawaii had record rainfall this winter because of an area of low pressure, known as a trough, high up in the atmosphere.
"That longwave trough started drifting westward back towards the islands, and effectively wipes out the inversion. Once the inversion is wiped out, we have a better chance for getting heavy rain in the islands," said National Weather Service Forecaster Tom Birchard.
With the trough over the state, showers can grow taller and fill up with more rain. Wet weather can also linger over one particular place or island.
"For Oahu on Tuesday, the upper level trough helped to focus the showers in a single line. The deep layer flow was moving them along but they were moving over the same location. Something similar happened with the record rainfall for Kahului last week," stated Birchard.
The upper level trough's more easterly location was also the reason for the windy start to the winter.
But our weather is about to change
"The longer term trend over the next couple of weeks is for the trough to shift west. And for low pressure to develop to the west of the islands, which would give us prevailing trade wind weather," said Birchard.
The shift to the west, would diminish the threat of heavy rain events and also shift storms across the Pacific Ocean more to the northwest. Which means Hawaii should see a return of more westerly surf swells.
That could help shift the disappearing sands back over exposed North Shore beaches.
Once the state transitions back to trade wind weather, there will still be trade showers, just not the record setting rain Hawaii has already seen.