HONOLULU (HawaiiNewsNow) – The Hawaii News Now First Alert Weather Team has declared that Sunday and Monday are First Alert Weather Days.
Strong northeasterly to easterly winds, heavy rainfall, and isolated thunderstorms are all possible over the weekend and into the beginning of next week.
A Flash Flood Warning has been issued for heavy rain around the Hamakua Coast on the island of Hawaii, where rain was falling at a rate of 4 to 5 inches per hour. The warning is in effect until 9 p.m.
A Flood Watch is in effect for all the main Hawaiian islands from Saturday afternoon through Monday afternoon.
A High Wind Warning will be in effect from 6 a.m. Sunday until 6 p.m. Monday for all islands except Niihau.
The storm system may also bring up to a foot of snow and 50 mile per hour winds to the summit areas of Mauna Kea and Mauna Loa, so a Winter Storm Watch is in effect from from Saturday afternoon through Monday afternoon.
What does this mean for the Punahou Carnival?
We’ve been getting lots of questions around the Punahou Carnival. It will start to get soggy Saturday with light to moderate showers. There could be heavier rain toward the end of Saturday evening as the system strengthens.
Here’s a timeline for the weekend:
First Alert Weather Day Timeline(Hawaii News Now)
Cold front moves in
Heavy rainfall and strong winds are expected this weekend as a cold front and upper-level disturbance move over parts of the state. This slow-moving front is forecast to stall over Maui Saturday afternoon.
This will lead to unsettled weather throughout the weekend and into the beginning of next week. Due to the upper-level nature of this system, rainfall is expected to be relatively scattered at times.
Models also suggest that a bulk of the rainfall is expected to fall over the windward portions of each island.
Strong winds to develop
Behind the front, strong east to northeasterly winds will develop, with the strongest winds late Sunday and Monday.
East to northeast winds of 20 to 30 miles per hour with gusts to 50 miles per hour will be possible Sunday morning. Winds are forecast to strengthen to 25 to 35 miles per hour with gusts to 60 miles per hour by late Sunday afternoon or evening.
Areas that will have the highest risk for strong winds will be mountain ridges, passes, and areas immediately south and west of mountains, including urban Honolulu valleys such as Moanalua, Kalihi, Pauoa, Manoa and Palolo.
Thunderstorms possible
This storm system will also receive upper-level support due to strong winds moving over the state high up in the atmosphere. These strong winds will lead to upward motion in the atmosphere, providing further vertical growth for any developing storm clouds. The upper-level support and increased instability in the atmosphere will lead to a few rumbles of thunder.
Further intensification of the heavy rainfall and isolated thunderstorm chances will occur late Saturday night into Sunday, and could continue into Monday.
Be prepared
Postpone any outdoor activities, such as hiking, until the weather improves.
If you are in a flood-prone area, be prepared to take quick action if a flash flood warning is issued, or if you observe flash flooding.
Strong winds may bring down trees and power lines so be prepared for power outages.
Loose outdoor items should be brought inside or properly secured. This includes tents and awnings. The wind will also be strong enough to blow away canopies that may be set up for Sunday’s big game.
Chief Meteorologist Jennifer Robbins has Hawaii’s most accurate First Alert Forecast every weeknight at 5, 5:30, 6, 9 and 10. Get weather updates every ten minutes on HNN Sunrise, weekdays with Guy Hagi and weekends with Billy V. Meteorologist Drew Davis has your forecasts on This is Now at noon, First at Four and Hawaii News Now at 6:30. And join Ben Gutierrez weekends.
Watch our previous coverage here:
Strong northeasterly winds, heavy rainfall, and isolated thunderstorms are all possible over the weekend and into the beginning of next week.Strong northeasterly to easterly winds, heavy rainfall, and isolated thunderstorms are all possible over the weekend and into the beginning of next week.
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