National Weather Service Weather Forecast Office

Synopsis:

On Tuesday afternoon, a small-scale area of low pressure, referred to as a "mesolow", formed over the Gulf of Mexico along a cold front which was moving into central Florida. This center of this feature was accompanied by a small band of showers and lightning storms as it moved onshore the west coast near the mouth of Tampa Bay. After pushing onshore, these storms then moved rapidly northeast at 35 to 40 mph across Pinellas, Hillsborough and Polk counties of western Florida, before crossing the Kissimmee River into northwestern Osceola county of east central Florida. With the "mesolow" feature acting to enhance low level wind shear and helicity, a condition which favors storms to acquire rotation, significant rotation was noted on doppler radar as the storms approached the Kissimmee area shortly after 5:30 pm. Hence, a tornado warning was issued for northwest Osceola and southern Orange counties at 5:36 pm. Over the next half hour the rotation within these storms weakened significantly as they crossed into southern and eastern Orange county. However, shortly before 6:00 pm, another cluster of storms developed rapidly over northwestern Orange county near Windermere and began to show signs of significant rotation. As these storms crossed over into Seminole county, a second tornado warning was issued at 6:09 pm.