Heavy Rains in Northern California

Heavy Rains in Northern California
  • Credit:

    Image produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC).

A powerful storm system brought high winds and heavy downpours to parts of central and northern California, causing localized flooding and knocking out power in the San Francisco Bay area. The weather station on Angel Island in San Francisco Bay measured strong wind gusts, including one that peaked at 156 kilometers per hour (98 miles per hour). This storm system was brought in by a powerful subtropical jet steam, which provided moisture and strong upper-level winds. The system spawned thunderstorms that brought lightning and sizeable hail around Sacramento. Coastal regions also measured heavy rainfall, though there was no widespread flooding there.

The Tropical Rainfall Measuring Mission (TRMM) monitors rainfall based on a near-real-time, Multi-satellite Precipitation Analysis (MPA) at NASA’s Goddard Space Flight Center. This image shows MPA rainfall totals for the central and northern West Coast from February 22 to March 1, 2006. The highest rainfall totals for the period are around 120 millimeters, about 5 inches, shown in red. These rainfall amounts occur along the western slopes of the coastal range, in the Klamath Mountains near the border with Oregon, and over the northern Sierra Nevada on the downwind side of the Sacramento Valley. The mountains forced moisture from the humid air rising over the slopes. MPA rainfall totals for the San Francisco Bay area are rather light, while the areas around Sacramento received a little over 70 millimeters, about 3 inches, shown in the brighter greens.

The TRMM satellite was launched into service in November of 1997. It was engineered to measure rainfall over the global Tropics using both passive and active sensors, including the first and only precipitation radar in space. TRMM is a joint mission between NASA and the Japanese space agency, JAXA.

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  • Data Date:

    March 1, 2006
  • Visualization Date:

    March 2, 2006
  • Sensor(s):

NASA - National Aeronautics and Space Administration