Hilo

Tonight: Mostly cloudy with scattered showers. Lows 63 to 71 near the shore to 54 to 59 at 4000 feet. Northwest winds up to 15 mph. Chance of rain 50 percent.

Tuesday: Mostly cloudy with scattered showers. Highs 79 to 87 near the shore to around 68 at 4000 feet. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 64 to 72 near the shore to 56 to 61 at 4000 feet. Northeast winds up to 10 mph in the evening becoming light. Chance of rain 70 percent.

Kona

Tonight: Mostly cloudy with isolated showers. Lows around 75 near the shore to around 53 near 5000 feet. Light winds. Chance of rain 20 percent.

Tuesday: Mostly sunny in the morning, then mostly cloudy with isolated showers in the afternoon. Highs 83 to 88 near the shore to around 67 near 5000 feet. South winds up to 10 mph shifting to the west in the afternoon. Chance of rain 20 percent.

Tuesday Night: Mostly cloudy in the evening then becoming mostly clear. Lows around 74 near the shore to 50 to 55 near 5000 feet. Light winds.

Waimea

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 63 to 72 near the shore to 55 to 63 near 3000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Tuesday: Breezy. Partly sunny with scattered showers. Highs 64 to 84. East winds 10 to 20 mph decreasing to up to 20 mph in the afternoon. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 65 to 73 near the shore to 57 to 64 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

Kohala

Tonight: Breezy. Mostly cloudy with scattered showers. Lows 63 to 72 near the shore to 55 to 63 near 3000 feet. East winds 10 to 20 mph. Chance of rain 50 percent.

Tuesday: Breezy. Partly sunny with scattered showers. Highs 64 to 84. East winds 10 to 20 mph decreasing to up to 20 mph in the afternoon. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 65 to 73 near the shore to 57 to 64 near 3000 feet. East winds 10 to 15 mph. Chance of rain 70 percent.

South Big Island

Tonight: Breezy. Mostly cloudy with isolated showers. Lows around 74 near the shore to around 54 near 5000 feet. Northeast winds up to 20 mph. Chance of rain 20 percent.

Tuesday: Breezy. Sunny in the morning, then partly sunny with isolated showers in the afternoon. Highs around 86 near the shore to around 68 near 5000 feet. East winds up to 20 mph. Chance of rain 20 percent.

Tuesday Night: Partly cloudy. Lows around 75 near the shore to around 54 near 5000 feet. East winds 10 to 15 mph.

Puna

Tonight: Mostly cloudy with scattered showers. Lows 63 to 71 near the shore to 54 to 59 at 4000 feet. Northwest winds up to 15 mph. Chance of rain 50 percent.

Tuesday: Mostly cloudy with scattered showers. Highs 79 to 87 near the shore to around 68 at 4000 feet. Northeast winds up to 15 mph. Chance of rain 50 percent.

Tuesday Night: Mostly cloudy. Scattered showers in the evening, then numerous showers after midnight. Lows 64 to 72 near the shore to 56 to 61 at 4000 feet. Northeast winds up to 10 mph in the evening becoming light. Chance of rain 70 percent.

Waikoloa

Tonight: Breezy. Mostly cloudy with isolated showers. Lows around 75 near the shore to around 55 above 4000 feet. East winds up to 20 mph. Chance of rain 20 percent.

Tuesday: Sunny in the morning then becoming partly sunny. Breezy. Highs 84 to 89 near the shore to 64 to 73 above 4000 feet. Northeast winds up to 20 mph.

Tuesday Night: Partly cloudy. Scattered showers after midnight. Lows around 76 near the shore to 53 to 58 above 4000 feet. Northeast winds up to 15 mph shifting to the east after midnight. Chance of rain 50 percent.

Detailed Forecast

Synopsis

In the wake of Tropical Storm Hone, drier air will continue to filter in and high pressure far north of the state will bring a typical moderate to breezy trade wind pattern that will continue through much of the week. Tropical Cyclone Gilma far east of the state will weaken as it approaches later this week and bring the potential for more rain.

Discussion

Current satellite imagery and radar show clouds and a few light showers on the outer periphery of Tropical Storm Hone moving across Oahu and Kauai this afternoon. As Hone continues it westward track and moves further away from the area, its associated moisture field will also clear out of our area and typical anticyclonic trades will return. Winds will continue to weaken as Hone's influence on the pressure gradient wanes, leaving breezy trades today and moderate to breezy trades for tomorrow, with isolated to scattered showers moving into windward and mountain areas.
The swath of drier air filtering in behind Hone's moisture field will be short-lived. CIMSS MIMIC satellite imagery shows this narrow swath of drier air followed by a broad moisture plume extending well out ahead of Hurricane Gilma. This moisture plume will move into the area as early as Tuesday night, bringing an uptick in windward and mauka showers through the end of the week. According to the latest National Hurricane Center's forecast, Gilma will pass through or near the island chain sometime Friday into Friday night as a weakening tropical depression. This will bring another break in the trade wind pattern, with local impacts depending on the track of this weakening system. Consensus among the guidance is that developing troughing northwest of the region will cause Gilma to recurve upon approach to the islands, potentially leading to a period of warmer weather featuring higher humidity and light southeast winds this weekend. A more southerly track would bring a greater probability of a wet trade wind type of pattern. The Central Pacific Hurricane Center will continue to monitor the progress of Gilma as it crosses into the Central Pacific Basin late tonight.
And finally, remnants of Hector will follow closely behind Gilma as potentially a weak surface trough with a diffuse moisture plume sometime Saturday night into Sunday. Little to no impacts are expected with this feature.

Aviation

The outer bands of Tropical Storm Hone continue to impact the western end of the state this afternoon. but are expected to move off to the southwest overnight. Drier air behind the storm has already built in across the remainder of the state. An easterly trade wind flow will become established by tomorrow morning and persist through midweek.
AIRMET Sierra remains in effect above 3000 feet for Kauai and northeast exposures of the Big Island. Conditions are expected to improve early this evening for Kauai, but may linger overnight across Windward Big Island.
AIRMET Tango remains in effect for moderate low-level turbulence downwind of island terrain. Conditions are expected to end early this evening as Hone moves further west.

Marine

Locally strong easterly winds and rough seas will continue through tonight through early Tuesday morning as Tropical Storm Hone tracks roughly 220 nm southwest of the state. The pressure gradient will gradually weaken over the region tonight through the week as Hone tracks away and Hurricane Gilma approaches from the east. The Small Craft Advisory has been scaled back to only include the typical windy waters around Kauai, Maui County, and the Big Island tonight as the winds begin to ease. Winds will further ease into the moderate to fresh category Tuesday through midweek.
Although the current forecast by the National Hurricane Center shows Gilma quickly weakening as it approaches and passes the islands to the north later this week through the weekend, any deviation in the forecast track could have a more significant impact on the Hawaiian waters this weekend. Refer to the latest advisories issued by the National Hurricane Center for more information on Gilma.
Surf along east facing shores will remain rough tonight, then quickly ease Tuesday through midweek as the easterly winds trend down. An upward trend is possible from Tuesday night onward, as a medium- period easterly swell from Gilma begins to fill in.
Surf along south facing shores will hold tonight due to a combination of a small background south swell and short- to medium-period south to southeast swell generated by Hone passing to the southwest. A downward trend back to the summertime average is expected Tuesday through midweek.
Surf along north and west facing shores will remain near the seasonal average this week, but could slightly rise this weekend for north facing shores as Gilma approaches the region.

HFO Watches/Warnings/Advisories

Small Craft Advisory until 5 AM HST Tuesday for Kauai Northwest Waters, Kauai Leeward Waters, Oahu Leeward Waters, Kaiwi Channel, Maui County Windward Waters, Maalaea Bay, Pailolo Channel, Alenuihaha Channel, Big Island Leeward Waters, Big Island Southeast Waters.

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Data Courtesy of NOAA.gov