CatchWindow fishing intelligence

Hilo, Hilo Bay, Kuhio Bay, HI Daily Water Report — August 27, 2026

Diving is today’s clear standout, and the rest of the bay is workable if you time it right. Hilo Bay is offering a rare window of clean, stable conditions that will appeal to anyone who can get on the water before the afternoon breeze kicks up. The representative wind sits at just 4 knots from the north-northeast, but the model shows gusts peaking near 19 knots around 1 p.m., so the morning and early evening are your friends today. Water clarity is the headline. Chlorophyll readings are oligotrophic—essentially blue, low-productivity water—and with modest wave energy and light wind through the morning, the nearshore visibility should be well above average for this stretch of coast. The diving score of 8.3 reflects that combination: calm surfaces, warm surface temps near 28°C, and a swell that’s long-period enough to not stir things up badly. That SST anomaly of +1.7°C means the water is noticeably warmer than what’s typical for late August. Surfers will find a consistent 1.6-metre swell from 78 degrees with a 7.6-second period, which is rideable but not crisp—the score of 7.6 is fair, though don’t expect barrels. The trade-off is that the wave height holds steady all day, so there’s no dramatic morning bump. Fishing scores a 6.5, which is middling. Solunar activity is strongest around the late-morning major period (10:46 to 12:46) and again near midnight, but the lack of tide data means you’re flying blind on water movement. The stable barometric pressure suggests no major weather shifts to trigger a feed, and light chop will keep the surface from being glassy. Kayakers and small-boat paddlers should treat the 5.7 score seriously: the representative wind is calm, but that 19-knot gust potential and 0.34-metre wind waves mean exposed paddles around noon could turn into a slog. Stick to the protected shoreline inside Kuhio Bay if you’re in a kayak. Boating scores a 6.9 and sailing a 6.1, both leaning on the same logic: the morning is fine, the afternoon gets sporty, and the southeast-facing exposure catches the swell directly. Nobody is getting blown off the water, but plan your return well before the gust window. The next few days show wave heights climbing slowly—by September 1, expect 1.8-metre swell and a shorter, chunkier period that will knock diving quality down. Precipitation chances stay high through the weekend, so today’s partly cloudy, low-rain setup is your best bet for clear windows. If you have one move today, make it a dawn or dusk dive before the breeze and the weekend swell arrive.