Wet Weather Nothing Unusual For First Part of April

The sun finally made more of an extended appearance in Hilo and other portions of the Big Island on Thursday, April 14, providing a little relief from what seemed like constantly wet and rainy conditions.

But despite how persistent the precipitation has been during the first part of April, a National Weather Service official says it’s nothing out of the ordinary.

“This time of the year is generally pretty wet on the windward side of the Big Island,” Kevin R. Kodama, senior service hydrologist for the National Oceanic and Atmospheric Administration and National Weather Service Weather Forecast Office in Honolulu, told Big Island Now in an email. “It is a bit wetter than normal, but still within the bounds of ‘near normal.’ I definitely would not call this unusual. In fact, it’s more of a return to normal conditions following a long period of unusually dry weather.”

Through Wednesday, April 13, according to data recorded by a National Weather Service station, Hilo has received 5.23 inches of rainfall since the beginning of the month. That’s 0.69 inches more than normal. The most rainfall recorded by the Hilo weather station, 0.95 inches, fell April 8, with the greatest 24-hour rainfall total of 1.02 inches on April 11-12.

Even West Hawai‘i, where it is normally more dry, has seen a little more rain since the beginning of April.

Data from the NWS Kailua-Kona weather station show half an inch of rain has fallen on the community through April 13, most of which, 0.30 inches, came on April 6. That 0.30 inches is also the greatest 24-hour rainfall total recorded by the station so far this month.

The rainfall total through April 13 recorded at the Kona station is 0.23 inches more than normal.

The wetter conditions have definitely been a departure from the rest of the year so far.

Kodama explained in his monthly rainfall summary for March that the central North Pacific weather pattern that produced generally dry conditions over the main Hawaiian Islands since early January continued into the first half of last month. A weak large-scale surface pressure pattern resulted in light winds, mainly from the east to east-southeast.

“Light wind patterns like these allow land and sea breezes to dominate the local conditions,” he said in his report, adding continued stable conditions aloft also prevented significant rainfall throughout most of March.

That large-scale weather pattern over the North Pacific finally shifted during the second half of March, resulting in an increase in rainfall over the state.

Unfortunately, continued dry conditions during the first part of last month only exacerbated drought in portions of the state, including areas of the Big Island.

“The drought on the Big Island covers portions of the North Kohala, South Kohala and leeward Hāmākua districts,” Kodama said in his email Thursday. “Very little rain has been occurring there and the area is under extreme drought.”

And with trade winds expected to persist, he said the likelihood of significant drought relief in those areas is rather low.

Kodama added that the east side of the Big Island currently isn’t experiencing drought.

For more about drought conditions, check out the U.S. Drought Monitor by clicking here.

Wet conditions look to be the norm for East Hawai‘i, at least for the foreseeable future.

“It looks like it will be pretty rainy along the windward side of the Big Island for at least another week,” Kodama said.

According to the National Weather Service forecast for Hilo through April 21, showers are likely through Monday, April 18, with scattered showers forecast from Monday night through the majority of the week. The sun looks to have the best chance of taking over Wednesday, April 20, but scattered showers are still in the forecast that day.

Find the Hilo forecast by clicking here.

The west side of the island also stands a chance of seeing some more rain in the next several days. The NWS forecast for Kailua-Kona shows chances for rain through Monday, with mostly sunny conditions returning by Tuesday, April 19.

Take a look at the Kona forecast by clicking here.