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Pentad Outgoing Longwave Radiation Anomaly

Data:   Outgoing Longwave Radiation ("OLR") anomaly (watts/m2) on a 2.5 x 2.5 deg. lat/lon grid Base Period for Climatology:  1974-present Data Source:  NCEP, Climate Prediction Center Description:  Pentad (5-day average, centered on date shown) outgoing longwave radiation as observed by polar-orbiting satellite.  Negative values imply increased cloudiness and enhanced likliehood of precipitation.  Positive anomalies imply decreased cloudiness/precipitation.  The relationship between OLR anomaly and precipitation is most reliable in tropical regions.