West Side

Today: Mostly sunny with isolated showers. Highs 72 to 82. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Haze. Lows 62 to 70. Light winds.

Sunday: Mostly sunny with isolated showers. Haze. Highs 72 to 82. Southwest winds up to 10 mph. Chance of rain 20 percent.

South Side

Today: Mostly sunny. Isolated showers in the morning. Highs 74 to 83. North winds 10 to 15 mph decreasing to up to 15 mph in the afternoon. Chance of rain 20 percent.

Tonight: Clear and haze. Lows around 65. Light winds.

Sunday: Mostly sunny. Haze. Highs 75 to 84. Southwest winds up to 10 mph.

North Shore

Today: Partly sunny with scattered showers. Highs 75 to 80 near the shore to around 63 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers. Haze. Lows around 67 near the shore to around 51 near 5000 feet. Light winds. Chance of rain 50 percent.

Sunday: Mostly sunny with isolated showers. Haze. Highs around 80 near the shore to around 65 near 5000 feet. Light winds. Chance of rain 20 percent.

Central Maui

Today: Mostly sunny with isolated showers. Highs 78 to 83. Northeast winds 10 to 15 mph decreasing to up to 15 mph in the afternoon. Chance of rain 20 percent.

Tonight: Mostly clear. Haze. Lows around 65. Light winds.

Sunday: Mostly sunny. Haze. Highs 80 to 85. Southwest winds up to 10 mph.

Upcountry

Today: Partly sunny with scattered showers in the morning, then mostly sunny with isolated showers in the afternoon. Highs 50 to 68. Light winds. Chance of rain 50 percent.

Tonight: Mostly clear with isolated showers. Lows around 42 at the visitor center to around 40 at the summit. West winds up to 10 mph. Chance of rain 20 percent.

Sunday: Sunny with isolated showers. Highs 51 to 68. West winds up to 15 mph. Chance of rain 20 percent.

East Maui

Today: Partly sunny with scattered showers. Highs 75 to 80 near the shore to around 63 near 5000 feet. East winds up to 15 mph. Chance of rain 50 percent.

Tonight: Mostly cloudy with scattered showers. Haze. Lows around 67 near the shore to around 51 near 5000 feet. Light winds. Chance of rain 50 percent.

Sunday: Mostly sunny with isolated showers. Haze. Highs around 80 near the shore to around 65 near 5000 feet. Light winds. Chance of rain 20 percent.

Lanai City

Today: Mostly sunny with isolated showers in the morning, then partly sunny with scattered showers in the afternoon. Highs 67 to 78. Northeast winds 10 to 15 mph decreasing to up to 10 mph in the afternoon. Chance of rain 30 percent.

Tonight: Partly cloudy. Haze. Lows 57 to 63. Light winds.

Sunday: Mostly sunny with isolated showers. Haze. Highs 66 to 77. Light winds becoming southwest up to 10 mph in the afternoon. Chance of rain 20 percent.

Kaunakakai

Today: Mostly sunny with isolated showers. Highs 65 to 83. East winds up to 15 mph. Chance of rain 20 percent.

Tonight: Partly cloudy. Haze. Lows 52 to 68. Light winds.

Sunday: Mostly sunny with isolated showers. Haze. Highs 66 to 83. South winds up to 10 mph shifting to the southwest in the afternoon. Chance of rain 20 percent.

Detailed Forecast

Synopsis

The first in a series of three cold fronts moving into the Hawaiian Islands over the next seven days has dissipated into a trough near Maui and the Big Island this morning. Another stronger cold front will approach Hawaii from the northwest late Sunday, bringing breezy southwesterly winds lasting into Monday. More significant showers will develop along this next frontal band as these clouds and showers march eastward down the island chain from Monday to Tuesday, before stalling out and diminishing near the Big Island on Wednesday. The third cold front appears to be the strongest of the three systems, and this next front will spread showers across the Hawaii region from next week Friday into the weekend. This strong cold front may bring periods of heavy rain and thunderstorms as it passes. Much cooler temperatures and drier conditions will blow into the region after frontal passage.

Discussion

Looking into the big picture satellite imagery this morning, we see lingering low clouds along windward mountain slopes are associated with the now dissipated cold front near Maui and the Big Island. These clouds are fairly thin with limited shower potential and will likely diminish later this morning as a brief period of light easterly trade winds returns to the region lasting into Sunday.
A brief period of southwesterly winds strengthen over the islands from Sunday night into Monday ahead of the next cold front approaching the state from the northwest. Some enhanced wind gusts are possible along north and east slopes of island mountain ranges during the overnight to morning hours. Another round of VOG (Volcanic smOG) hazy emissions from Kilauea Volcano on the Big Island that will briefly return to all smaller islands east of Kauai by Sunday. However, wind directions will quickly veer from the west to northwest as the front swiftly moves eastward down the island chain on Monday; driving away this VOG plume. Expect around 0.50 inches of rainfall over the western islands of Niihau, Kauai and Oahu with this next system with locally higher amounts possible. The frontal cloud band will begin to break apart over island mountains and slightly lower rainfall amounts are expected as front weakens and passes over Maui and the Big Island. Cool and dry northwesterly winds will blow in after the front passes each island, decreasing shower trends from west to east from Tuesday into Wednesday.
The third cold front in the series will be stronger still with the potential to bring periods of heavy rain and thunderstorms to all islands as the system sweeps down the island chain from next week Friday into the weekend. Unfortunately it remains to early to include an island by island heavy rain or thunderstorm forecast as these mesoscale (smaller scale) banding features will need to wait until the forecast time period grows shorter. Much cooler and drier air will blow in following frontal passage over each island. Expect several days of colder weather due to drier air moving in behind the front. This drier air more efficiently radiates surface heat back into outer space, significantly lowering our overnight low temperatures. Winter weather highlights with strong winds may also develop over the Big Island summits by next Saturday morning. Snow levels will hover between the 11,000 to 12,000 foot level with this system, based on the latest operational model runs. At seven days out in the forecast time period, many of these weather impacts and timing details remain fuzzy, and the forecast will likely change as our weather model solutions continue to evolve over time. Stay tuned.

Aviation

A weakening trough lingering over Maui County will continue to bring light showers and increased cloud cover through the morning, resulting in periods of MVFR conditions. Winds across the islands will remain northeast to east early, then become light and variable, allowing localized land and sea breezes to develop through much of the weekend.
AIRMET Sierra remains in effect for tempo mountain obscuration above 2000 feet for Oahu, Molokai, Lanai, and Maui. Conditions are expected to improve later this morning as the trough continues to erode and dissipate.

Marine

Early this morning, a weakening trough is located over the eastern coastal waters. Moderate to locally fresh northeasterly winds are prevailing over much of the area, while gentle and variable winds persist around the Big Island. Trades will continue to weaken today as high pressure north of the state moves eastward. These lighter trade winds will give way to southeast winds tonight as a surface ridge is pushed over the island chain. South to southwest winds will develop on Sunday and will build to fresh to strong levels Sunday night and Monday as another, stronger front approaches. This front is expected to pass down the island chain Monday night and Tuesday, and a Small Craft Advisory may be needed for some waters as winds peak Monday into Tuesday.
Large to extra-large surf will continue into today along north and west facing shores, with another round of elevated surf due early next week. A complex storm low far northwest of Hawaii generated overlapping west-northwest to northwest (295 to 320 degrees) swells that are currently affecting the islands. NOAA offshore buoys northwest of Kauai are still running well above guidance early this morning, with total seas of 15 to 18 feet and significant swell period energy ranging between 14 and 17 seconds. Based on these observations, and the fact that nearshore buoys at Hanalei, Waimea, and Pauwela are also already running a couple feet above guidance, surf heights for north and west facing shores were bumped up a bit for today from the previous forecast. However, headlines remain unchanged. A High Surf Warning remains in effect for north and west facing shores of Niihau, Kauai, Oahu, and Molokai today. Additionally, a High Surf Advisory remains in effect for north facing shores of Maui and west facing shores of the Big Island. A Small Craft Advisory is also in place for waters exposed to the elevated seas. As the swell declines, the warnings and advisories will likely be dropped this evening or tomorrow morning. Another round of potentially larger northwest swell is expected late Monday through early Thursday.
A Coastal Flood Statement remains in effect through Monday. During this time, higher than predicted tides will produce minor flooding along vulnerable low-lying coastal infrastructure as well as some some beach erosion during peak high tides between midnight and sunrise. The elevated tides will also contribute to runup and beach erosion though the rest of the early morning hours this morning, and again late tonight into early Sunday morning, along north and west shores exposed to the large swell.
Surf along east- and south-facing shores will remain small through the week.

HFO Watches/Warnings/Advisories

High Surf Warning until 6 PM HST this evening for north and west facing shores of Niihau, Kauai, Oahu and Molokai.
High Surf Advisory until 6 PM HST this evening for north facing shores of Maui and west facing shores of the Big Island.
Small Craft Advisory until 6 PM HST this evening for all Hawaiian Coastal Waters and Channels exposed to this large northwest swell.

Data Courtesy of NOAA.gov