CatchWindow fishing intelligence

Boulogne-sur-Mer, France Daily Water Report — August 28, 2026

Today's winner is diving, and it's not a close call. The harbor is serving up a stellar 8.8 out of 10 for anyone with a mask and fins, matching the last few days' top marks. Winds are light out of the southwest at just 6 knots, with manageable gusts through the morning and afternoon. The sea surface is sitting at a balmy 20.6°C, which is over two degrees warmer than average for late August, so the thermocline should be comfortable even on a longer dive. Waves are a negligible 0.36 meters on a short 4-second period, and the swell is almost flat at 0.26 meters. With visibility near 29 kilometers above the surface, you're unlikely to have much turbidity stirred up. Now, the tradeoff. That same calm setup that's perfect for divers means this isn't a surfer's playground. The 4.7 score reflects the minimal wave action and short period — you'd be bobbing more than riding. Boating and kayaking are solid mid-range options at 6.5 and 6.0, respectively, but the wind will build through the afternoon, with gusts forecast to hit nearly 30 knots by 20:00. If you're taking a boat or paddlecraft out, make it an early morning or pre-noon trip, and keep an eye on that rising pressure trend — currently at 1008 hPa and climbing — which suggests stabilizing conditions after any morning clouds. The rain window from 10:00 to 14:00 carries only a trace of precipitation, so it's more of a passing threat than a washout. Fishing scores a 6.2, slightly improved from yesterday's 6.1, buoyed by the full moon and solunar major periods around 01:10 and 13:10. Chlorophyll levels are elevated at 4.82 mg/m³, which the model interprets as a positive sign for bait, but without tide data, the window is harder to pin down — use those solunar peaks as your best bet. Wildlife watchers get a respectable 7.0, again leveraging the moon phase and light winds. Looking ahead, Thursday brings a sharp uptick in wave heights to 1.2–2.5 meters and an 83% chance of rain, which will tank the diving score and make boating less appealing. Friday and Saturday stay unsettled with similar wave action and persistent precipitation chances. The real window for a return to calm seas appears Monday into Tuesday, when waves drop below a meter and the rain chance falls to just 15% on the first. Best bet: Hit the water before noon today if you want the glass, because by dinner the gusts will be howling.