Het weer in Jacó, Costa Rica in december

Regulars are specific this area reads as genuinely drier than areas further south along the same coast, where the rainy season doesn't properly end until mid-to-late December, though conditions here have shifted from the old reputation of reliably rain-free North winds - even the tail end of the month can now bring real rain some years. Our row backs that hot, genuinely wet read, 27.6C reading as a scorching 33C, over 24C nights feeling 29C, with a substantial 278.6mm of rain across 28.5 days and humidity at 86 percent. Regulars are consistent Costa Rica's weather is genuinely location-dependent given how many separate weather systems affect the country, no single verdict applying evenly countrywide. The sea sits at a bath-warm 29.1C. The record: 9.9 hours of sun, a 9.7 kph wind and AQI 32.

The consensus on April for this coast is that it is transitional - not the driest, nowhere near the wettest - and our row proves it exactly: 242.9mm here against 581.8mm in May and 829.3mm in October. What the numbers cannot show is the timing, and the board supplies it: rain on the central Pacific coast comes in the afternoon or overnight, it is warm rain, and the weather apps that promise rain all day every day are wrong about the shape while right about the odds. Our 27.6 rainy days is that same statement. Pack fast-drying clothes rather than cotton, and something light to keep it off. Heat holds at 29.1C reading as 36C, with a 30.3C sea. The record: humidity 83 percent, 10.4 hours of sun and AQI 36.

January opens the hottest, driest run of the Costa Rican year, with strong sun and lower humidity - and regulars still say to expect some rain most days, generally in the afternoon or at night. Our 22.2 precipitation days across 120.4mm is that, five millimetres a day, and one visitor's accounting is the clearest version: roughly eight hours of rain across a week, five of them after dark. Their weather apps had predicted rain daily. The date worth knowing is the 6th: the first days of January are peak holiday travel, and waiting until after about then means the Christmas crowds have gone and prices ease, though it stays high season. A light poncho and a small umbrella cover it. The record: 28.4C over 24.4C reading as 34C, a 28.9C sea and AQI 33.

March is inside the driest and hottest stretch of the Costa Rican year, and our row's 19.7 precipitation days would say otherwise until you read the phrase regulars use: intermittent thunderstorms that do not produce much rain. That is 87.4mm spread across those days, under five millimetres each. Being socked in for days would be strange now; rain is always possible and rarely severe. What the dry season does bring is heat on the coast - 29.6C over a 25.4C night reads as 36C and 30C at 77 percent humidity, and with the Pacific at 29.9C there is nothing cool to get into. Their own figures, high 80s by day and mid 70s at night, match ours closely. The record: 11 hours of sun, a 12.4 kph wind and AQI 38.

Jacó-area forum threads describe August as one of the milder rainy-season months on the Central Pacific coast - the typical pattern is clear mornings, afternoon showers lasting 2-4 hours starting around 4pm, and starry evenings, with more of the day turning wet as the month progresses toward September. One local detail worth knowing: heavy rain washes mud down from the hills, which can turn even normally turquoise water like nearby Playa Blanca temporarily brown. Forum consensus was to schedule outdoor activities for the morning and treat the afternoon rain as background noise rather than a trip-ender, with lush green scenery and thinner crowds as the trade-off.