Tropics
The tropic of Cancer is at 23° 27' North latitude and the
tropic of Capricorn is at 23° 27' South latitude. These two
lines extending around the earth, north and south of the equator
respectively, are the formal limits of the tropic zone (aka
torrid zone). Between these two lines, the sun does pass directly
overhead on at least one day during the year. This fact influences
the temperature and other qualities of the climate in the tropical
zone.
Tropical Climate in San Salvador
San Salvador is at approximately 24.05° North latitude. This
places the island just slightly north of the tropical zone; the sun
never passes directly overhead in San Salvador but it comes very close
to it on June 21 (summer solstice). The climate of San Salvador is
tropical. The record high temperature is 95° F and the record low
temperature is 46° F; it is a frost-free climate. The average air
temperature goes from a low of 71° F in January to a high of 83° F
in August. Night temperatures do fall to 64° F in January but are a
warm 77° F in August. Sea breezes of a 9 mph average are common
throughout the year. The sea temperature dips to 73° F in February
but rises to 85° F in August. This tiny island of land in a vast
volume of warm ocean water has a tropical climate in spite of its
latitude just within the temperate zone.
Is there a US geographic reference point for San Salvador?
The Bahamian archipelago extends in an arc from the south-eastern coast
of Florida to the east and then south toward the Tropic of Cancer. San
Salvador is on the very outside (74.55° W longitude) of this curve
and is battered by the Atlantic Ocean on its east coast. Miami is the
nearest large US city to San Salvador. An almost-straight-line of flight
from Miami, Florida through Nassau, Bahamas extends on to San Salvador
at a distance of about 350 miles from Miami.
May-June Climatology Data (1961-1990 means)
Based on historical records, we can expect weather conditions to be mild
with some rain. You won't want a jacket except perhaps at night or on a boat,
and a windbreaker will probably be enough. A water-resistant windbreaker
is likely needed for at least one or two of our days. Because we arrive just
before summer solstice, the sun will be almost directly overhead; prime
conditions for sunburn! You will need sunscreen and cover-up clothing, and
we will likely all get a tan, in spite of our precautions. Please excuse the
English units in this document...but US students are more likely to be able
to judge these values better than their metric counterparts.
Mean Daily Temperatures: High 86° Low 74° F
Record Temperatures: High 92° Low 55° F
Relative Humidity: Morning 82 Afternoon 68 %
Wind: 9 mph
Rain per Month: 6 inches
Water Temperature: 78° F
This page © Ross E. Koning 1994.
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