Fading small surf is all that we’ll have today although some areas may still pick up near shoulder-high surf from time to time. This northwest well won’t have much punch left in it but at least we aren’t flat yet. Thankfully a new west-northwest to northwest is expected to arrive Tuesday into Wednesday which should boost the surf back to well overhead levels, but also well under advisory levels. Once again, the west-northwesterly component of this swell will be shadowed by Moloka`i, so expect smaller surf the closer you get to town. A very small south swell is passing through the islands today but it won’t offer much. A low is fading just west of the dateline today but it should have pushed a moderate west-northwest to northwest swell our way, which would reach our shores by Thursday. The models have been quite accurate so far with the development of a low tomorrow, forming east of Japan. However, there is a good possibility that we could see a better swell than original forecast. The low is modeled to take better aim toward our islands Wednesday into Thursday, potentially capturing a fetch aimed very nicely toward Hawa`ii. The resulting swell would likely arrive Friday well over advisory levels lasting for several days. Check back for updates as this develops.
North and northwest facing shores will still offer tiny to small surf around 1-4 foot with a few slightly higher sets still possible further east. Upper West shores won’t see much, maybe 1-3 foot. Windswell along the east and northeast facing shores is dropping but may still be around 3-5 foot. South facing shores may see tiny surf in some areas but most breaks will stay flat at 0-2 foot.
Wind and Tide Information
Low tide at Kahului will slowly drop through the morning hours into the afternoon to a flat low of 0.0 foot at 3:26 PM this afternoon, then rising to a high of 2.09 foot at 11:52 PM late this evening. The sunrise was at 06:59 am this morning and will set at 06:20 pm this evening. The Moon is in a waning crescent phase and will reach New Moon this Saturday.
Sunset: 6:40 PM
Weather Outlook for Monday
Trade winds expected to remain moderate to strong through Wednesday. The prevailing dry conditions will modify during the next couple of days as trade wind showers increase across the islands, favoring windward and mauka areas. By Wednesday, a wetter trade wind weather pattern is expected to begin and remain in place through the end of the week.
The current dry weather conditions will begin changing early Monday and through the rest of the work week as atmospheric moisture gradually increases. Latest satellite imagery shows some low level stratocumulus cloud layers upstream of the islands and reaching the windward coastal areas at times.
Subsidence aloft, sustained by a mid level ridge, continues to keep inversion heights around 4k ft. But the increasing moisture will help in gradually raising the inversion during the next couple of days. This will allow for a return of windward and mauka showers as the trades become stronger.
Meanwhile, the high pressure system northeast of the state will continue to migrate away from the area while being replaced by another high sliding into the central Pacific from the west. Also, models continue to depict the development of a weak low well to the east of the Big Island through the first half of the week. This synoptic scenario will favor strong trades across the main Hawaiian islands especially windward and over areas prone to terrain/induced gusty winds under a northeast wind regime. A wind advisory remains in effect for the Haleakala summit, north Kohala, areas near volcanoes national park and Lanai. Wind speeds will decrease a little on Tuesday, but still with gusty periods expected as the high pressure system north of the islands gradually migrates eastward. Then a wetter trend will be in place by Wednesday as moisture levels increase significantly due to the influence of the aforementioned low east of the Big Island. Latest model data suggest values increasing to around 1.5 inches by late Wednesday.
Meanwhile, global models are in fair agreement in terms of the passage of a mid/upper level trough also in the Wednesday/Wednesday night time frame. This will certainly destabilize the air mass over the islands with much colder temps aloft, to around -14 or -15 c. Therefore, expect a more active weather pattern for the middle and later part of the week, including chances of winter weather over the Big Island summits.
Central Valley (Kahului, Spreckelsville):
Sunny, windy. Highs 76 to 83. Northeast winds 15 to 30 mph with gusts to 45 mph.
Leeward West (Lahaina, Ka`anapali):
Sunny, breezy. Highs 74 to 81. Northeast winds 15 to 25 mph with gusts to 45 mph.
Windward West (Wailuku, Waiehu):
Partly sunny in the morning then clearing. Scattered showers. Breezy. Highs 67 to 77. Northeast winds 10 to 25 mph with gusts to 45 mph. Chance of rain 50 percent.
Windard Haleakala (Hana, Haiku, Makawao):
Mostly sunny with scattered showers. Highs around 77 at the shore to around 63 at 5000 feet. East winds 10 to 20 mph with gusts to 35 mph. Chance of rain 50 percent.
Leeward Haleakala (Kihei, Wailea, Makena):
Mostly sunny. Highs around 80 at the shore to around 65 at 5000 feet. South winds up to 10 mph with gusts to 35 mph.
WIND ADVISORY IN EFFECT UNTIL 6 PM HST MONDAY. Mostly clear with isolated light showers. Windy. Lows around 46 at 7000 feet to around 43 at the summit. Northeast winds 20 to 30 mph with gusts to 45 mph. Chance of rain 20 percent.