December to April is typically the dry season in Panama. Winter winds from the north bring stronger currents and these bring nutrient rich cooler waters to the surface around seamounts, reefs and shorelines. The cooler water temperatures trigger the huge sardine runs that rely on these upwellings. This in turn stimulates gorging by all the accompanying predators like Yellowfin Tuna, Bonito and Black and Blue Marlin, Sailfish and Wahoo. Fishing can be exceptional this time of year with windy days being more of the norm. Surface action is often furious and can be insane at times. It is prime for popping to large surface boils of tuna. The tuna in these situations are not particularly fussy and will hit pretty much anything. Marlin fishing can be really good this time of the year. Much of the fishing this time of year may be done inshore on the protected leeward side of the islands because of the wind.
Jigging and popping is very productive for inshore species when the wind abates or when along protected shorelines. In a nutshell, the dry season in Panama can be said to be typified as having sunny dry days, windy conditions and good quantities of fish hooked.
The rainy season for Panama starts in May and usually ends by December. That being said this region is also one of the driest in the country, so don't be discouraged if you're in the city and are experiencing monsoon conditions. It's unlikely to be the same at Cebaco Bay. At this time of year we often see bands of rain in this region with generally flat seas. When offshore, it's easy enough to skirt these localized rain events unless we're visited by a tropical depression that may bring a few days of uninterrupted rains. These rain events increase in frequency until around Sept/Oct. Even then it is often that we see 1 sunny day out of 2 days or so of rain. Upside is that seas are mostly calm and skies are cloudy or overcast when not raining so you'll be mostly fishing in the shade! Calm seas also offer fishing further offshore.
Fishing can be very excellent this time of year, with Tuna growing bigger and in greater numbers. They also seem to forage further inshore. This offers a fantastic opportunity for fishermen to land their personal best tuna on light tackle. Tuna season really peaks during the months of July - September with impressive increases in size and quantity. This season is also typified by a greater variety of species caught and the trophy sized specimens of Roosterfish, Cubera Snapper and Yellowfin Tuna that can be caught on poppers and jigs.