Costa Rica Guide by Paul Glassman
Travel Seasons
Even at the budget level, hotel space is extremely tight in Costa Rica from December through April, when most foreign visitors arrive, when Costa Ricans themselves take their holidays, and when the roads in outlying regions are most easily passable.
Of course, rain can be a damper on travel
from May through November, the so-called "green season." But in parts of
the country, especially the east, there isn't that much of a difference
between June and January. Many hotels lower their rates or are willing
to strike a deal during periods when their occupancy rates drop.
CLIMATE AND WEATHER
Dry and "Green" Seasons
Most visitors arrive in Costa Rica during the northern winter and spring, and for obvious reasons. This is when it's best to get away from the cold, of course. But it also coincides with the dry season, from about November through April, when the western side of Costa Rica receives hardly any rain, and when temperatures are usually most pleasant.
But there are a few good words to be said for the rainy times, which promoters have taken to calling the "green season"—and not without reason. On the western side of the country, the annual drought is broken in May, and the fields turn green and exuberant. Facing the Caribbean, where the rains take no annual vacation, the downpours are heavier and last longer. For rafters, the rivers are full of water. And for wise travellers, hotel occupancy drops, and so do rates.
And, though it's the rainy season, it never (well, hardly ever), rains all day. That's because weather forms in a different way from in the temperate latitudes, where a mass of clouds could stay in one place for days. In Costa Rica, a rainstorm is usually a daily phenomenon in season, blowing up from the coast on winds that follow the warming of the day, and dispersing after a few hours.
Then there are differences in climate between the temperate zones and Costa Rica. In the United States, latitude largely determines climate—Florida is warm, Georgia is pleasant, Minnesota is frigid in winter. In Costa Rica, despite "tropical" latitudes, mountain barriers, altitude and prevailing winds create zones that vary from chilly to humid and sweltering, throughout the year. These zones are right next to each other, and you can change your climate according to your mood. If you're feeling cold and damp in Monteverde in February, hop on a bus, and in a couple of hours you can get to a dry and sun-baked beach on the Gulf of Nicoya—and pass through a continent's worth of climates in the process.
Here is a general picture of the zones of Costa Rica.
The Central Valley
The highland climate of the major cities—San José, Cartago, Heredia and Alajuela—is often called "eternal spring," a term that is not used merely to attract tourists. Temperatures are in the low seventies Fahrenheit (about 22 Centigrade) during the day throughout the year. High mountains and volcanoes to the north of San José block the clouds that blow in from the Atlantic, and it rains only from April to November or December, when winds are from the Pacific. But a long rainy day is a rarity in the Central Valley. Mornings are generally clear, followed by a few hours of heavy downpour in the afternoon. Sometimes the rain can last into the night. Clouds hold in the heat of the day, and nights are generally warm. The rainy season is called invierno (winter), even though Costa Rica is in the northern hemisphere. In the dry times, or verano (summer), not even the thought of rain occurs. Days are uniformly warm and sunny. Nights are clear, and the temperature can sometimes drop into the fifties (about 10 Centigrade).
Pacific Coast
Down toward the Pacific coast, the climate is hotter. In Puntarenas, daytime temperatures are in the nineties (above 32 degrees Centigrade) throughout the year. But at the beaches, refreshing breezes moderate the heat. The rainy season is the same as in the Central Valley, but precipitation is heavier. The exceptions are the extreme north and extreme south. The Guanacaste plain suffers periodic droughts, which bother farmers more than visitors. And around Golfito, near Panama, peculiarities in the mountains and winds bring rains throughout the year.
Eastern Lowlands
On the Atlantic slope of Costa Rica, storms may blow in at any time, though rainfall is lightest from February through April and in September. Precipitation is over ten feet at Limón in most years, and even higher to the north. Storms appear suddenly and with a frightening fury, but they are usually quickly gone. Temperatures are generally as hot on the Caribbean as on the Pacific, and the humidity is more enervating.
Cold Country
The higher altitudes are cooler. Frosts occur above 2150 meters (7000 feet) during the dry season. And atop volcanoes and in the Talamanca mountains, temperatures can plunge from warm to below freezing in a few hours.
