Weakly Rotating Thunderstorm Near San Francisco, 1930 UTC 12/8/97

Base Reflectivity, 1/2 Deg Tilt, 1930 UTC

Strong, 53 dBZ core, Southwest of SFSU

Storm Relative Radial Velocity, 1/2 Deg Tilt, 1930 UTC

Storm-relative velocity couplet indicated

Visible GOES 9 Sat Image,  1930 UTC

Position of Cell Indicated

Lowering Southwest of San Francisco State at 1937 UTC, 8 December 1997 (See Images Above)

Funnel cloud observed on this lowering disappeared about five minutes before photo. Unfortunately, photographer did not have digital camera while observing funnel and had to run down 5 flights of stairs and back to get it.

Possible Funnel Cloud on Outflow Shelf South of Bay Bridge at 1503 UTC, 8 December 1997

Thunderstorm with cloud-to-ground lightning passed just south of Bay Bridge.  Possible funnel cloud about 10 km due south with rain core to the right of the image.  There was also lots of scud around, so this may not have been funnel cloud but just some inflow cloud tag material.

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