textproduct: Honolulu

SYNOPSIS

Moderate to breezy trades will continue through at least the middle of next week. Showers will generally favor windward and mauka areas, particularly during the overnight through early morning hours each day. Tropical Storm Lowell remains far ESE of the main Hawaiian Islands, and uncertainty regarding its track and intensity forecast remains high at this time.

DISCUSSION

Radar and satellite imagery show that drier air has filtered in across the state this afternoon, with only isolated showers currently moving into windward and mauka areas. Looking upstream on satellite, a band of open-celled cumulus will bring a slight uptick in windward and mauka clouds and showers late this afternoon and into the evening.

Robust high pressure to the far north will continue to help drive moderate to breezy trades across the state over the next several days. With ridging persisting over the region, shower activity will be suppressed, but minor upticks can be expected during the overnight to early morning hours and as plumes of moisture filter through.

Forecast confidence will drop over the latter half of next week and become low by next weekend. The National Hurricane Center continues to track Tropical Storm Lowell in the eastern Pacific, which was located about 1275 miles east-southeast of Hilo as of 11 AM HST this morning. With a wide spread in model guidance regarding both the track and intensity of this system, its too early to predict any potential impacts to Hawaii at this time.

AVIATION

VCSH expected through the afternoon hours across the island chain this afternoon into the overnight hours. Moderate trade wind pattern prevails with VFR conditions through the TAF period. Occasional MVFR conditions due to passing showers/lower CIGs. Expect low CIGs and SHRA over windward and mauka slopes most areas.

AIRMET Tango is in effect for mod low-level turb lee of terrain and may be needed for a few days.

MARINE

Extensive surface high anchored north of the islands maintains moderate to locally strong trades through next week. The Small Craft Advisory remains in effect.

The S swell that peaked just below the advisory threshold on Friday declines over the next few days. A long period S swell brings increasing surf to S and exposed W shores beginning Tuesday and peaking on Wednesday near the High Surf Advisory threshold. Surf along E shores remains choppy due to trades over and upstream of the islands. A small medium period east swell from Tropical Storm Iselle has filled in and will diminish during the next 24 hours.

FIRE WEATHER

Moderate to breezy trades will continue through the weekend and into next week, and with RHs expected to dip to near 45 percent across some leeward communities each afternoon, moderate to near critical fire weather conditions are expected. Rainfall will be confined mainly to windward and mauka zones during this time. Tonight`s temperature inversion is expected to be around 7000 to 8000 feet, with only minor day to day fluctuations expected through the weekend.

HFO WATCHES/WARNINGS/ADVISORIES

Small Craft Advisory until 6 PM HST Sunday for Alenuihaha Channel-Big Island Leeward Waters-Big Island Southeast Waters- Maalaea Bay-Pailolo Channel.