LIHUE — In the past 30 days, 16 record highs have been tied or broken at Lihue Airport.
Mix that in with record-high-temperature days recorded on other islands across the state, and Hawaii tied or broke daily high-temperature records nearly every day in September.
That’s continued through October, with the latest recorded record-tying event occurring Oct. 5 in Hilo. The daily high that day was 88 degrees and tied the record set in 2015.
Officials with the National Weather Service point out that Hawaii breaking or tying daily heat records isn’t a major news happening — temperatures don’t typically change much, and so a few-degrees fluctuation will break or tie a record.
But, NWS says there are some factors contributing to higher temperatures around the island, and the first one has to do with the ocean.
“Sea-surface temperatures have been 2 to 4 degrees warmer than normal around Hawaii,” said NWS meteorologist Ian Morrison.
He says Hawaii’s land masses are basically sitting in a warm “bathtub,” and it’s contributing to warmer temperatures on land.
A change in the trade winds has also contributed to higher temperatures in Hawaii, with winds coming from the east or southeast rather than east-northeast directions.
“Wind that is coming in from the east-southeast will go over warmer water, and winds coming from the northeast come over cooler water before arriving in the islands,” Morrison said.
That enhances moisture content and temperature of those winds and contributes to more humid conditions.
Additionally, after heavy rains in late June, Hawaii’s been experiencing drier conditions, according to NWS. With those drier conditions comes less cloud cover and more heat.
“Then there’s the overall climate-change thing, a planet-wide warming of the Earth,” Morrison said.
Rain and slightly cooler temperatures are in the forecast for the next week, and that has to do with the interplay between the mountains, the trade winds and a bit of tropical moisture that’s making its way to the islands.
NWS is forecasting light winds and sea breezes on windward sides, and limited, scattered showers with nighttime cloud clearing.
Then comes the rain.
Passing showers and increasingly wet, east-southeast trade winds will contribute to more moisture, and NWS says it could be Friday before things start to dry out.
“Friday night we should get dry trade winds that’ll go through the weekend, with limited windward showers,” Morrison said.
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Jessica Else, environment reporter, can be reached at 245-0452 or jelse@thegardenisland.com.
