Photo credit: Sebastian Gabriel
west kauai
today: Breeze. Mostly sunny with isolated showers. The highest point near the coast is about 89 degrees and the highest point above 3,000 feet is about 76 degrees. East winds reaching 20 mph. The chance of rain is 20%.
tonight: partly cloudy. Breeze. Low pressure is 69 to 74 degrees near the coast and around 61 degrees above 3,000 feet. East winds reaching 20 mph, becoming 10 to 15 mph after midnight.
on Monday: Mostly clear in the morning then becoming partly clear. Highs will be around 90 degrees near the coast and around 76 degrees above 3,000 feet. East wind 10 to 15 mph, decreasing to 15 mph in the afternoon.
South Kauai
today: Breeze. Mostly cloudy with scattered showers. High temperature 80 to 87 degrees. The chance of rain is 50%.
tonight: Breeze. Mostly cloudy with showers. Lowest temperature 69 to 74 degrees. The chance of rain is 20%.
on Monday: Partly sunny. There are scattered showers in the morning. Highest temperature 81 to 88 degrees. The chance of rain is 20%.
kauai mountains
today: Mostly cloudy. Breeze. There will be more showers in the morning and scattered showers in the afternoon. Highest temperatures range from 74 to 87 degrees in the valley and 62 to 67 degrees above 4,000 feet. East wind 10 to 20 mph. The chance of rain is 70%.
tonight: Breeze. Mostly cloudy with scattered showers. Lowest temperatures range from 66 to 72 degrees in the valley and around 58 degrees above 4,000 feet. East winds reaching 20 mph will increase to 10 to 20 mph after midnight. The chance of rain is 50%.
on Monday: Cloudy and breezy. There will be scattered showers in the morning and scattered showers in the afternoon. Highest temperatures range from 75 to 88 degrees in the valley and 63 to 68 degrees above 4,000 feet. East wind 10 to 20 mph. The chance of rain is 50%.
North Kauai
today: Partly sunny. There will be more showers in the morning and scattered showers in the afternoon. Highest temperatures will be 78 to 90 degrees. The chance of rain is 70%.
tonight: Mostly cloudy with showers. Lowest temperature 65 to 74 degrees. The chance of rain is 20%.
on Monday: Mostly cloudy with showers. Highest temperatures will be 78 to 90 degrees. The chance of rain is 20%.
East Kauai
today: Mostly cloudy. There will be more showers in the morning and scattered showers in the afternoon. Highest temperature 74 to 86 degrees. The chance of rain is 70%.
tonight: Mostly cloudy with showers. Low pressure 66 to 76 degrees. The chance of rain is 20%.
on Monday: Mostly cloudy with showers. Highest temperature 75 to 86 degrees. The chance of rain is 20%.
summary
The high pressure system north of the Hawaiian Islands will continue to gradually weaken and slowly drift westward over the next few days. Trade winds will continue to blow at moderate to locally breezy levels today before decreasing to milder speeds Monday through Friday. Cloud and shower trends are still expected to increase slightly throughout the morning as weak tropical waves continue to move across the islands. Otherwise, a high-altitude ridge of high pressure will hover over the island chain this week, producing strong subsidence and stable conditions limiting shower activity.
discuss
A weak tropical wave will slowly move across the western islands this morning and shower activity is expected to increase slightly in the morning. The trough will weaken and move away from the state later this afternoon and evening as a more stable ridge of high pressure reestablishes over the islands.
Conditions are expected to be more stable under this ridge pattern, with sinking inversion heights in the 4,000 to 6,000 foot range, limiting vertical cloud development and causing a dramatic reduction in clouds and showers across the state. This dry weather pattern will continue throughout the week, with only brief showers expected in windward and mountainous areas, favoring overnight into early morning. High-level cirrus clouds associated with the subtropical jet stream will drift over the islands this week, enhancing sunrise and sunset colors.
The high pressure system north of the Keys will continue to move westward away from the state this week. Global models suggest the incised lows will be embedded in broader ridges in the northern part of the state. This weaker ridge pattern will keep trade winds in the moderate to moderate range Monday afternoon into Friday. In the extended forecast, another high pressure center will establish northeast of the Hawaii area by Saturday and our trade wind speeds will increase slightly into next weekend.
aviation
Breezy trade winds will continue into tonight. Low clouds and showers will favor windward and moka areas, especially this morning with a few showers dumping to the leeward at times. Conditions should improve in most areas by this afternoon.
AIRMET Sierra remains effective for mountain shelter on windward portions of Kauai, Oahu, Molokai, and Maui. Conditions should improve in most areas later this morning.
AIRMET Tango remains effective for moderate low-level turbulence over all island terrain and downwind. The AIRMET may last all day.
ocean
Strong surface high pressure to the north of the state will maintain locally strong trading tonight. Therefore, the Small Craft Warning for typically windy areas around Maui County and the Big Island has been extended through tonight. As said high pressure moves westward, trade wind speeds are expected to generally drop into the mild to fresh range by Monday.
Small to medium sized south swells will continue to bring small waves to south facing coasts today. A small, prolonged south-southwest swell (200 degrees) is expected mid-week, which will increase swells along the south-facing coast.
Surf along the East Coast will remain choppy with short term winds, then slowly ease into Monday's trade winds. Local wind and waves may hit some north and south facing coasts throughout the day. A minor northwest west swell background wave may arrive late Tuesday into Wednesday, bringing minor fluctuations to the north-facing coast.
fire weather
Breezier trade winds and lower relative humidity will keep fire weather concerns heightened in leeward areas today. Sites like west Maui and leeward Kohala on the Big Island are of particular concern. Trade winds will remain in the moderate to breezy range today and then tend to drop to more moderate levels Monday through Friday as the pressure gradient over the state eases.
Most leeward areas will remain dry. Brief showers will move into windward areas mainly overnight. Humidity levels will return overnight with good to excellent results. The exception to this humidity rule is at altitudes in the 4,000 to 8,000 foot range, where periods of warmer temperatures and dry conditions may occur within or above the subsidence inversion level.
HFO Observations/Warnings/Recommendations
A small craft advisory is in effect for Maalaea Bay, Pailolo Channel, Alenuihaha Channel, leeward waters of the Big Island, and waters southeast of the Big Island until 6 a.m. Monday (EST).
Data provided by NOAA.gov
