February was a cloudy and, in some places, a rainy month for much of the southern United States and Mexico. Heavy rains flooded southern California, Nevada, Utah and Arizona. This image hints at patterns of cloud cover during February. The image is a measurement of outgoing longwave radiation, the heat emitted by the Earth’s surface. Clouds are cooler than land, so outgoing longwave radiation is less intense where there are clouds. The above image shows anomalies—where February 2005 differed from average values measured in February 1979-1995. Regions where there were more clouds than normal are blue, while areas with fewer clouds are red. The blue regions seen here confirm the days of rain that southern North America experienced in February. This image was derived from measurements made by the TIROS Operational Vertical Sounder (TOVS) onboard the NOAA-POES satellite series.
NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of Assaf Anyamba and NOAA National Center for Environmental Prediction.
