Rain Showers Expected Until Wednesday

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The blustery trade winds will continue through Wednesday before gradually diminishing over the rest of the week.

Showers will become more frequent tonight through Wednesday, with some short downpours forecast in the windward and mountain portions of the country.

Following a period of drier weather on Thursday and Friday, it is possible that precipitation could build again during the weekend.

The presence of high pressure to the north of the state is helping to keep the trade winds blowing across the state.

Rain showers and low clouds are riding the trade winds onto the windward Big Island and Maui this morning, while the remainder of the state sees a generally clear sky.

A more structured band of showery low clouds approximately 125 miles to the northeast will arrive in the islands this evening, kicking off a wave of rainy trade wind weather over the state that will last until Wednesday afternoon.

During this period, some heavy downpours might be predicted as a weak upper trough persists over the islands, causing instability in the surrounding environment.

Trade winds will lessen, and drier weather will be predicted throughout the second part of the week. A high-pressure surface system moves into the eastern Pacific, and an airmass of drier air passes across the islands.

On the other hand, the upper trough is still there, so isolated downpours are still a possibility.

Forecast confidence is low beyond Friday due to disagreements among models on how to deal with forming a standard pressure system and cold front that is likely to build northwest of the islands over the weekend.

As this low grows and goes to our west, it has a lower potential for rainfall effect on the islands.

At the same time, the GFS develops and takes it closer to the state, where it has a higher possibility for more noticeable rainfall over the following few days.

According to the current projection, the ECMWF is the most likely option, and other global models are also trending in that direction. Because of this, forecasters are expecting east to southeast trade winds, with showers centered over windward and mountainous regions this weekend.

However, as models get closer to a solution, expect the long-term outlook to shift.