One of the METs can probably answer this one better. I believe you are correct with your observation of a funnel cloud. Which is actually a tornado that is not touching the ground.
I checked the NWS Ruskin Local Storm Reports for July 3rd and this is the only one I found.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
312 PM EDT THU JUL 03 2008

..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..

0302 PM WATER SPOUT 5 SW SIESTA KEY 27.23N 82.62W
07/03/2008 GMZ853 FL TRAINED SPOTTER

RECEIVED NUMEROUS CALLS ABOUT A LARGE WATERSPOUT 5 MILES
SOUTHWEST OF SIESTA KEY.
http://www.srh.noaa.gov/printable.php?pil=LSR&sid=TBW&date=2008-07-03%2019:13:45

I don't know how close Lakeland is to the above location. But some of the Florida Waterspouts that I've seen on television can be seen for many miles. Due to the topography of the land and height of the cloud bases.