Residents of San Juan, Puerto Rico will remember 2010 as the wettest year onrecord.Throughout the year, 89.51 inches of rain accumulated in the city. This isnearly double the normal amount of yearly rainfall, which is 50.76 inches.
Despite the excessive amount of rain, rain fell on 199 of the 365 days, whichis nearly the average amount of rainy days in a year (average is 202 days). SanJuan did, however, break 2 records on the way to the yearly record. The firstrecord was the number of rainfall amounts over 0.25 of an inch, which occurred95 times. The other record was the number of 1 inch or more rainfall amounts,which occurred 28 times in 2010.
San Juan was not the only location in the region to experience the excessiverainfall.
Puerto Rico as a whole reported 132 percent of normal rainfall, while theVirgin Islands reported 172 percent of normal rainfall for the year.
In addition, Saint Thomas recorded their second wettest year on record, whileSaint Croix reported their seventh wettest year on record.
Two factors contributed to the unusually wet conditions across Puerto Rico andthe Virgin Islands. The first contributing factor was the El Nino during thedry season (December through April). When El Nino's occur during the dryseason, there tends to be an increase in rainfall throughout the northernCaribbean Sea.
The second factor was the onset of a strong La Nina during the wet season (Maythrough November). La Nina's that occur during the wet season also tend toproduce more rain to the northern Caribbean Sea.
These two factors have lead to excessive rainfall throughout the entire year.
Story by Rob Miller, Senior Meteorologist
