SR/SSD 97-43


Technical Attachment

Tampa Bay Coastal Flooding Seminar

August 29, 1997

Charles Paxton

NWSO Tampa Bay Area, Florida

The Tampa Bay Area National Weather Service Office hosted a Coastal Flooding Seminar at the Knight Oceanographic Research Center in St. Petersburg, Florida. The forum was a multi-agency function, with participants from county, state and federal levels. It was organized by the NWSO Marine Focal Point, Dan Sobien, and Prof. Mark Luther of the University of South Florida (USF) Department of Marine Science. This was the first such meeting in the Southern Region to address upcoming changes in coastal flood forecast responsibility by NWS coastal offices. The seminar was attended by NWS forecasters from offices in Tallahassee, Jacksonville, Melbourne and Miami, and by USF faculty and students.

Michelle Baker, Director of Emergency Management (EM) for Pasco County, discussed the effects of coastal flooding and the NWS Coastal Flood Program from an EM perspective. She relayed the importance of methods of tide measurement, working with common datums, and the effects evacuation decisions can have on a population.

Mario Valverde, Marine Program Leader at NWS Southern Region Headquarters in Fort Worth, spoke briefly about the future of the marine program and scheduled changes for Stage Two of the NWS modernization program. He discussed National Data Buoy Center (NDBC) plans for refurbishing and upgrading coastal and buoy equipment with year-end (FY1997) funds.

Mike O'Brien, a forecaster at NWSFO Miami, reviewed past coastal flooding events, reviewed NWS regulations, and described the mechanics of issuing a coastal flood watch or warning.

Dr. Bob Weisberg (USF) reviewed the physics behind coastal flooding. He related wind-driven currents, Ekman currents and bottom topography to Florida's unique coastal features. Dr. Weisberg discussed how a wider continental shelf affects coastal flooding, partly causing higher storm tides from the northern part of Tampa Bay northward through the Florida Big Bend area. He also mentioned seasonal differences, noting that water levels around Florida are about a foot higher in summer than winter, due to a combination of lower atmospheric pressure and the decrease of density in the warmer water.

Dr. Huijun Yang (USF) presented animated results from the West Florida Shelf Model, showing the evolution of water levels along the coast related to the approach and landfall of Tropical Storm Josephine. Dr. Boris Galperin (USF) discussed a coastal flood model being created for the NWS by the University of Rhode Island and himself. He also showed animated model results depicting currents around Louisiana barrier islands during Hurricane Andrew.

NWS attendees then joined a second departmental seminar with USF Prof. Mark Luther who explained plans for placement of funded oceanographic and meteorological sensors on or near the West Florida Shelf.

The working lunch at the St. Petersburg Yacht Club allowed operational forecasters to ask the coastal flooding experts informal questions, and to form ties that will prove useful for future training and research.

After lunch, attendees visited the USF Department of Marine Science facilities which included tours of:

the Physical Oceanographic Real-Time System facility and a

description of how the server collects and distributes coastal data;

the department's computing facilities;

the Ocean Modeling and Prediction Laboratory;

Dr. Weisberg's Lab;

and the docks, to view a buoy which is to be deployed as part of the West Florida Monitoring Network.

The workshop was very successful in reaching its goals of providing a cost efficient, well-rounded program to prepare forecasters for coastal flood watch and warning responsibilities. Future joint workshops that will address specific marine forecast aspects are planned with the University of South Florida.