Leftover surf out of the north-northwest will continue to provide our north shores with head-high surf, but the strong local winds will destroy the conditions in most locations. There should still be some swell around tomorrow at slightly smaller levels and another much smaller northwest swell is expected to arrive Wednesday courtesy of a compact dateline low, but it probably won’t amount to much. The next chance for surf won’t come until Friday as another west-northwest to northwest swell arrives. The source for this swell is developing just east of Japan and is heading toward the central Aleutian Islands. Moderate surf is possible over the weekend from this swell, but don’t expect much more that that. The long-range forecast isn’t holding much promise after that. Strong upstream tradewinds should push in a building windswell over the next few days, potentially near or reaching advisory levels of 8 foot on the face. Local winds will keep this windswell sloppy and choppy.
North and northwest facing shores should still offer surf in the 4-6 foot range and some of the better exposed breaks could see larger sets. Expect poor conditions though. Upper West shores may also see some surf in select areas around 1-3+ foot and we could see some windswell starting to wrap in as well. East and northeast facing shores should have a rising but sloppy short-period windswell in the 3-5 foot range today, potentially reaching advisory levels by mid-week or earlier. The out-of-season south swell along our south facing shores is pau and most breaks should come in flat at 0-3 foot although some areas may wrap in some small windswell. Good luck.
Wind and Tide Information
High tide at Kahului was 2.47 foot at 12:51 AM just after midnight last night, dropping to a low of 1.03 foot at 7:05 AM this morning, then rising to a high of 1.54 foot at 11:21 AM shortly before noon before once again dropping to a low of -0.45 foot at 6:05 PM early this evening. The sunrise was at 06:51 am this morning and will set at 05:47 pm this evening. The Moon is in a waning crescent phase and will reach New Moon Wednesday.
Sunset: 5:45 PM
Weather Outlook for Monday
Trade winds will become strong and gusty this week, thanks to high pressure building north of the islands. Limited moisture will keep rainfall amounts light Monday and Tuesday. Trade wind showers may increase toward the middle of the week as an upper level disturbance passes close to the islands. The strong trades may blow some showers over to leeward areas from time to time.
The sprawling Kona low to our west which has been keeping our background flow from the ESE will be moving away today. This will allow high pressure far to our northeast to merge with another high and strengthen through tonight. Starting on Tuesday the high will very slowly move south and weaken, but still strong enough to maintain brisk trades for much of the week. It is possible that we may have to issue wind advisories later this week for some of the localized windiest spots, but at this point expecting the inversion to remain high enough to not cause widespread problems.
Model agreement is excellent with the surface features, but at the upper levels, not so much. Weak upper level ridging holds over the islands through about Tuesday. Gfs and NAM pinch off an upper low to our northeast Tuesday night and move it quickly westward just to the north of the islands Wednesday. The NOGAPS and ECMWF maintain an upper low or trough east of the islands through midweek, then begin to close off a stronger upper low that approaches the islands next weekend. The GFS eventually starts to come around, showing an upper low starting to develop over the islands around that time too.
Each of these features in the various models come with their own flavor of how unstable it will be over the islands, but the one thing missing from most of the models, at least for now, is significant moisture. Until the models learn to behave, it seems prudent to go with just enhanced mainly night and morning trade wind showers, starting about Wednesday and continuing into Thursday. The strong low level winds will easily allow any showers to blow leeward on the smaller islands.
Central Valley (Kahului, Spreckelsville):
Sunny. Isolated showers in the morning. Windy. Highs 75 to 84. Northeast winds 10 to 15 mph with higher gusts increasing to east 20 to 30 mph in the late morning and afternoon. Chance of rain 20 percent.
Leeward West (Lahaina, Ka`anapali):
Mostly sunny. Isolated showers in the morning. Breezy. Highs 74 to 82. East winds 10 to 25 mph. Gusts up to 40 mph in the late morning and afternoon. Chance of rain 20 percent.
Windward West (Wailuku, Waiehu):
Partly sunny in the morning then clearing. Scattered showers. Breezy. Highs 63 to 79. East winds 15 to 25 mph. Gusts up to 40 mph increasing to 50 mph in the late morning and afternoon. Chance of rain 50 percent.
Windard Haleakala (Hana, Haiku, Makawao):
Partly sunny with showers likely in the morning, then mostly sunny with scattered showers in the afternoon. Breezy. Highs around 75 at the shore to around 61 at 5000 feet. East winds 10 to 25 mph with gusts to 45 mph. Chance of rain 70 percent.
Leeward Haleakala (Kihei, Wailea, Makena):
Sunny. Isolated showers in the morning. Highs around 84 at the shore to around 64 at 5000 feet. East winds 10 to 15 mph shifting to the southwest in the late morning and afternoon. Gusts up to 45 mph. Chance of rain 20 percent.
Sunny with isolated showers. Windy. Highs around 64 at 7000 feet to around 58 at the summit. East winds 20 to 30 mph. Chance of rain 20 percent.