CatchWindow fishing intelligence

Hilo, Hilo Bay, Kuhio Bay, HI Daily Water Report — September 4, 2026

Today around Hilo Bay and Kuhio Bay belongs first to surfers and divers. Surfing scores 8.1 and diving 8.0, with wildlife close behind at 7.8; fishing and boating sit at 5.9, kayaking 5.8, and sailing 5.3. Those numbers describe how the mix of wind, swell, timing, and water temperature lines up—they are not a green light to ignore the sea. A light northeasterly around 5 knots, ranging only 1.4 to 5.5 with the day’s strongest gust 12.6 knots near 16:00, keeps wind chop small. Forecast waves hold 2.0 to 2.3 meters, with a 2.06-meter swell at 7.45 seconds from 77 degrees and a 9-second pulse in the combined sea; the lowest height is 2.02 meters near 23:00, so “calmest” is still a solid two-meter set. Tiny 0.2-meter wind waves and a 0.2 m/s current toward 180 degrees complete the marine picture. That consistent easterly energy is what lifts the surf score. Diving’s 8.0 rides the same modest wind, the 26.8 C surface temperature (marine field 27.4 C, about 0.7 C above average), and available clarity data—not the 38.56-kilometer atmospheric visibility, which is a different thing. Skies are fully overcast, UV a mild 2.6, and a rain window runs from midnight through 13:00 even though representative precipitation is still 0 millimeters. Air is 25.8 C, feeling nearer 29, with a 22.3–26.1 C day. Pressure is 1011 hPa and falling. Fishing’s middling 5.9 leans on solunar majors at 05:30–07:30 and 17:30–19:30 (sunrise 06:06, sunset 18:35), last-quarter moon, light wind, and that falling barometer; wildlife uses the same solunar windows and wind. Against CatchWindow’s recent days, fishing has eased from the 7.8–8.3 stretch through September 2, while surfing has ticked up from the high sevens and diving is in line with most of the past week. Waves stay in the 2.0–2.3-meter band through the 6th before easing later in the week, with rain chances jumping, especially 92 percent on the 6th. Best bet: take the polite wind and that stubborn easterly swell for a surf session before the next wetter days arrive.