Brasília, March 30, 2004 (Agência Brasil) - The phenomenon that struck the shore of Santa Catarina in the pre-dawn hours on Sunday (28) was an extratropical cyclone. According to a technical note released jointly by the Space Research Institute (Inpe) and the National Institute of Meteorology (Inmet), cyclones exhibit low internal temperatures and winds that rotate in the same direction from ground level to the higher altitudes.

From the moment when the eye of the cyclone and bands of rotating clouds appeared, there arose speculation that it could be a hurricane. The process of hurricane formation is different from the process observed in the South. The note explains that, in its final stage, the system lost its cold core and began to present rotation in the reverse direction in the higher altitudes. This behavior is typical of a cyclone with hybrid characteristics. The technical note states that the phenomenon will be studied and analyzed in greater depth by teams from the Meteorological Centers.

The note explains that hurricanes represent a phenomenon formed in the warm waters of tropical oceans, exhibiting high internal temperatures and winds that rotate in different directions at ground level and the higher altitudes, that is, around 12 kilometers above sea level.

MONITORING

The cyclone observed this weekend along the coast of Santa Catarina and the north of Rio Grande do Sul was accompanied by the Meteorological Centers from March 24, when a small area of atmospheric instability formed around 1000 kilometers off the coast of Santa Catarina and began to take shape with a cyclonic circulation.

Mathematical projections indicated that the cyclone would continue in the direction of the coast of the South of the country, although it was uncertain in which locale the impact would be greatest.

Between Saturday night and the early morning hours of Sunday, the cyclone struck the continent, especially in the areas between the south of Santa Catarina (SC) and the northeast of Rio Grande do Sul (RS), between the cities of Criciúma (SC) and Torres (RS). Strong winds and rains were observed during this period. From the damage that was caused, it can be inferred that the winds reached a velocity of 150 kilometers per hour. Over the course of the day on Sunday, the rains continued over the mountainous regions of the two states, and the cyclone gradually subsided in intensity.

Translator: David Silberstein