Waianae Coast

Today: Partly sunny in the morning, then cloudy with isolated showers in the afternoon. Highs 74 to 83. Southwest winds up to 10 mph. Chance of rain 20 percent.

Tonight: Cloudy with isolated showers. Lows 62 to 71. Light winds becoming northeast up to 10 mph after midnight. Chance of rain 20 percent.

Monday: Mostly cloudy in the morning then becoming mostly sunny. Highs 75 to 83. Northeast winds up to 15 mph shifting to the east in the afternoon.

South Shore / Honolulu

Today: Partly sunny in the morning, then cloudy with isolated showers in the afternoon. Highs around 81. South winds up to 10 mph. Chance of rain 20 percent.

Tonight: Cloudy with isolated showers. Lows around 69. East winds up to 10 mph. Chance of rain 20 percent.

Monday: Cloudy in the morning then becoming partly sunny. Highs around 81. Northeast winds 10 to 15 mph.

East Honolulu

Today: Partly sunny in the morning then becoming cloudy. Isolated showers. Highs 73 to 81. Light winds. Chance of rain 20 percent.

Tonight: Cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows around 67. Northeast winds 10 to 15 mph. Chance of rain 30 percent.

Monday: Cloudy in the morning then becoming partly sunny. Highs 74 to 81. Northeast winds 10 to 15 mph.

Ewa Plain

Today: Partly sunny in the morning, then cloudy with isolated showers in the afternoon. Highs 70 to 81. East winds up to 10 mph shifting to the south in the afternoon. Chance of rain 20 percent.

Tonight: Cloudy. Isolated showers in the evening. Lows 60 to 68. Light winds becoming northeast up to 10 mph after midnight. Chance of rain 20 percent.

Monday: Mostly cloudy in the morning then becoming mostly sunny. Highs 71 to 81. Northeast winds 10 to 15 mph.

North Shore

Today: Mostly cloudy with isolated showers. Highs 75 to 81. South winds up to 10 mph shifting to the northwest in the afternoon. Chance of rain 20 percent.

Tonight: Cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows around 65. East winds up to 10 mph. Chance of rain 30 percent.

Monday: Cloudy with isolated showers in the morning, then partly sunny in the afternoon. Highs 75 to 81. East winds 10 to 15 mph. Chance of rain 20 percent.

Central Oahu

Today: Partly sunny in the morning then becoming cloudy. Isolated showers. Highs 70 to 80. Light winds. Chance of rain 20 percent.

Tonight: Cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows 60 to 68. Northeast winds up to 10 mph. Chance of rain 30 percent.

Monday: Cloudy with isolated showers in the morning, then partly sunny in the afternoon. Highs 70 to 80. Northeast winds up to 15 mph shifting to the east in the afternoon. Chance of rain 20 percent.

Windward Oahu

Today: Cloudy with isolated showers. Highs 68 to 80. East winds up to 10 mph. Chance of rain 20 percent.

Tonight: Cloudy with scattered showers. Lows 58 to 69. East winds up to 10 mph. Chance of rain 40 percent.

Monday: Mostly cloudy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 67 to 79. East winds 10 to 15 mph. Chance of rain 40 percent.

Koolau Leeward

Today: Partly sunny in the morning then becoming cloudy. Isolated showers. Highs 68 to 81. Light winds. Chance of rain 20 percent.

Tonight: Cloudy. Scattered showers in the evening, then isolated showers after midnight. Lows 58 to 69. Northeast winds up to 15 mph increasing to 10 to 15 mph after midnight. Chance of rain 30 percent.

Monday: Cloudy and breezy. Scattered showers in the morning, then isolated showers in the afternoon. Highs 67 to 80. Northeast winds 10 to 20 mph. Chance of rain 40 percent.

Detailed Forecast

Synopsis

A light east to southeast wind pattern will continue through this afternoon as a weakening cold front approaches Kauai from the west breaking down the ridge over the Hawaii Region. Local scale onshore seabreezes will form over terrain sheltered leeward areas due to the lack of large scale winds. The eastward movement of this front will stall out near Kauai today and Monday as the front dissipates near the western edge of the state. Moderate to locally breezy easterly trade winds will strengthen across the Hawaii region from Monday through Wednesday with brief passing windward and mountain shower activity. Trade winds weaken again with returning sea breezes from Thursday onward as another weak cold front approaches the islands from the northwest.

Discussion

The satellite imagery this morning shows a large band of high level jet stream cirrus clouds blanketing the islands. Expect cloudy skies from these high clouds to continue through Monday as a weakening cold front approaches the Hawaiian Islands from the west. The short range forecast guidance continues to show the forward motion with this front stalling out and dissipating near Kauai through Monday. Periods of enhanced showers are possible starting tonight over the western islands of Kauai and Niihau with some brief showers spreading as far east as Oahu and Molokai. Lighter winds will continue to produce sea breezes along terrain sheltered leeward slopes of each island.
This period of light winds will begin to transition back to trade winds by Monday. These easterly trade winds will strengthen into the moderate to locally breezy range on Tuesday and Wednesday with brief passing windward and mountain showers, favoring the overnight to early morning hours.
By Thursday, another weak cold front approaches the islands from the northwest direction, weakening the ridge north of the islands, and producing another round of east-southeasterly winds lingering into the weekend. Strong stable subsidence will keep shower activity to a minimum on Thursday. However by Friday an upper level disturbance over the region may increase shower activity as temperature inversion heights rise into the 7,000 to 8,000 foot range lasting through the weekend.

Aviation

A light to moderate ESE wind regime will persist today as a weakening front continues to approach Kauai from the west. Light winds will continue to allow daytime seabreezes and nighttime land breezes to occur. Chances for showers over the western half of the state increase due to lingering moisture from the stalled front. Showers will continue over windward sections of the Big Island through the morning. Primarily MVFR conditions will occur within showers, while VFR prevails elsewhere.
AIRMET Sierra is in effect for tempo mountain obscuration over the southeast slopes of the Big Island and is expected to continue through the morning hours. No other AIRMETS are expected.

Marine

Moderate to locally fresh east to southeast winds will continue today as a weakening front stalls and diminishes near the western end of the state. This will allow localized land and sea breeze conditions to develop near sheltered coasts, particularly for the western end of the state closer to the trough. Fresh to locally strong easterly trades will return by Tuesday as surface ridge strengthens to the north, at which time Small Craft Advisories will likely be needed for the typically windy waters of Maui County and the Big Island.
Surf along north and west-facing shores will continue to trend up slightly today as a fresh west-northwest swell arrives from a broad gale that was located south of the Aleutians near the Date Line. This swell will peak late today into Monday before gradually lowering by midweek.
Surf along exposed east-facing shores will trend up slightly today as a fresh, short- to medium-period northeast swell from a gale centered around 1200 nautical miles northeast of the state arrives. Short-period and choppy conditions are expected to return by Tuesday as fresh trade winds redevelop and expand upstream of the state.
Surf along south-facing shores will remain near the seasonal average into March.

HFO Watches/Warnings/Advisories

None.

Data Courtesy of NOAA.gov