The TRMM satellite flew above the post-tropical cyclone remnants of former hurricane Norbert on September 8, 2014 at 0849 UTC (1:49 AM PDT). This image shows TRMM rainfall derived from the Microwave Imager (TMI) and Precipitation Radar (PR) instruments overlaid on a 0900 UTC GOES-EAST enhanced Infrared image.

These data show that only a small amount of light to moderate rainfall was located around Norbert's center of circulation. This view shows that heavy rainfall was being produced over the southwestern United States.

This 3-D image was made from TRMM Precipitation Radar (PR) data. It shows that some showers located to the west of Norbert's center of circulation weren't very high.

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The TRMM satellite flew over the southwestern United States again on September 8, 2013 at 1205 UTC (5:05 AM PDT). At that time a cluster of intense thunderstorms was found in Arizona directly below the satellite. Rain was measured by the TRMM Precipitation Radar (PR) instrument falling at a rate of over 62 mm (2.4 inches) per hour in some downpours.

For over sixteen years the TRMM's Precipitation Radar (PR) has been providing three dimensional vertical profiles of precipitation from the surface of the earth to heights of about 12 miles (20 kilometers). This 3-D view shows a 15dBZ isosurface using radar reflectivity values returned to the satellite from heavy rain within powerful thunderstorms over Arizona. Some thunderstorm tops reached heights of 13.5 km ( about 8.4 miles) and returned radar reflectivity values of over 51 dBZ.

Yesterday, the moisture spreading north-eastward from tropical storm Norbert caused flooding over inland areas of southern California. Today, widespread flooding in Arizona has led the Governor to declare a state of emergency in the state. At least one person has been reported drowned in Arizona.