According to the classification of Köppen (modified),
in most of Cuba the predominant climate is of the tropical warm type,
with rainy station in the summer. In general it is enough accepted to
express that the climate of Cuba is tropical, seasonally humid, with marine
influence and semi-continental features. However, in the country it is
also reported the presence of other climatic types. For example, in the
highest areas in the main mountainous systems the climate of humid tropical
type of forest exists, rainy during the whole year; or the one observed
in the fringe coastal south of the provinces of Santiago de Cuba and Guantánamo,
which classifies as tropical relatively dry with few rains.
As decisive factors in the formation of the climate of Cuba are identified
the quantity of solar radiation that one receives, the particularities
of the atmospheric circulation on the country, and the different influence
of the physical-geographical characteristics characteristic of the national
territory.
For its geographical position, Cuba is located in really next latitude
to the Tropic of Cancer, what conditions the reception of high values
of solar radiation during the whole year, determining the warm character
of its climate. Also, it is in the frontier among the areas of tropical
and extra-tropical circulation, receiving the influence from both with
seasonal character. In the season that goes approximately from November
to April, the variations of the time and the climate become more remarkable,
with abrupt changes in the daily time, associated to the step of frontal
systems, to the anti-cyclonic influence of continental origin and of centers
of drops extra-tropical pressures. Of May to October, on the contrary,
few variations are presented in the time, with the influence more or less
marked of the Anticyclone of the North Atlantic. The most important changes
are linked with the presence of disturbances in the tropical circulation
(waves of the east and tropical hurricanes.)
In Cuba, the temperatures are generally high. The values annual means
go from the 24ºC in the plains to 26ºC and more in the oriental
costs, being reported inferior magnitudes at the 20ºC in the Sierra
Maestra higher parts. The season of November to April is less hot and
it is known as winter, while the months of May to October, hotter, they
receive the summer name. The registered absolute maximum and minimum temperatures
are of 38.6ºC (Guantánamo, August 7, 1969) and 0.6ºC
(Bainoa, February 18, 1996), respectively. As it is typical in the tropical
climates, the daily variation of the temperature is bigger than the annual
one.
The relative humidity stocking is high, with near averages to 80%. The
daily maxima, generally, superiors to 90%, happen to sunrise, while the
minima descend, at noon, up to 50-60% inside the territory. The most humid
areas are the regions Westerner and Central, together with the main mountainous
nuclei.
In Cuba the component winds reign. Of November to April directions of
the first quadrant prevail, due to the influence of the meteorological
systems of the winter season; while in the summer the winds rotate more
to the southeast, mainly with the reserve of the anti-cyclonic wedge.
The maximum speeds of the wind happen at the passing of the cold fronts,
extra-tropical hurricanes, local storms, hurricanes, among other phenomena.
Of interest are also the systems of local winds, with the presence of
a central convexes belt and the coastal influence of the sea breezes and
earth that are reinforced or they weaken in dependence of the predominant
flow of the wind. The orography is the factor of fundamental transformation
of the normal régime of the local wind. The anti-cyclonic influence
is major during the whole year, with values higher and bigger gradients
of pressure in the months of winter.
The element that varies more in the climate of Cuba is the precipitations.
In most of the territory, two fundamental seasons are recognized: rainy
(of May to October) and not very rainy (of November to April). In the
first one falls 80% of the total of annual rain approximately. In the
northeast of the oriental region and in the mountainous areas, these averages
change, because during the months of November to April is when the biggest
rain totals take place. It is in fact, in that area of the country where
the areas are located with more pluviosity, with values above the 3 000
mm a year.
On the other hand, in the south coast of the provinces of Guantánamo
and Santiago de Cuba, to leeward of the Sierra Maestra and of the Sagua-Baracoa
Group, is reported 600 mm and less, with conditions of aridity. The biggest
rain volumes are associated to some of the most important meteorological
phenomena (tropical hurricanes, cold fronts, tropical waves, etc.) or
they have their origin in the day heating, almost always happening in
hours of the afternoon in form of episodes of short duration. In presence
of meteorological systems of great scale they can take place by periods
of big rains, mainly in the months of May-June and September-October.
Cuba possesses high values of evaporation that arrive until the 2300
mm in the Cauto Valley and in the south coast of Guantánamo. The
lowest magnitudes register in the mountainous areas (annual 1100 mm).
In general, it is increased from occident to east, and in their distribution
space-storm they influence the latitude and structure of the soil, the
distance to the coast, the exhibition degree to the wind, among others.
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