At Eye on the Storm, meteorologist Jeff Masters notes that Tampa/St. Petersburg has been rated the most vulnerable metropolitan area in the country to storm-surge damage, to the extent that a Category 4 storm that makes landfall just north of the area could do an estimated $230 billion in damage. Adds Masters:
Most of the population in the four-county Tampa Bay region lives along the coast in low-lying areas, about 50 percent of it at an elevation of less than 10 feet. More than 800,000 people live in evacuation zones for a Category 1 hurricane, and 2 million people live in evacuation zones for a Category 5 hurricane, according to the 2010 Statewide Regional Evacuation Study for the Tampa Bay Region. Given that only 46% of the people in the evacuation zones for a Category 1 hurricane evacuated when an evacuation order was given as 2004’s Category 4 Hurricane Charley threatened the region, the potential exists for high loss of life when the next major hurricane hits.
Two weeks ago, Helene didn’t even get all that close, but still walloped the metro area:
Despite its center passing 130 miles (205 km) to the west of Tampa Bay on Sep. 26, Hurricane Helene brought the bay its highest storm surge since record-keeping began in 1947, with water levels 5-8 feet above dry ground. According to local station fox13news.com, damage was heavy in the four-county Tampa Bay region: Pinellas County (home of St. Petersburg) had 28,000 damaged buildings, Pasco County had 9,900, and there were 8,600 in Manatee and Sarasota counties combined. Twelve storm-related deaths occurred in Pinellas County, two in Manatee County, and two in Hillsborough County.
Masters outlined the most troubling possible scenarios for Tampa:
Our five top hurricane-specific forecast models – the HWRF, HMON, HAFS-A, HAFS-B, and COAMPS-TC – have been painting some extremely ugly possible futures for Tampa Bay from Hurricane Milton. At least one run in recent days from all of these models have predicted Milton would achieve Cat 4 or Cat 5 strength on Tuesday or Wednesday. Many of the runs have shown a landfall just north of Tampa Bay, which would maximize the surge in the bay. However, many recent runs of these models have predicted that high wind shear and dry air would combine to disrupt Milton’s core before landfall, causing rapid weakening, with a potential Cat 1 or Cat 2 landfall resulting. Unfortunately, such a rapid weakening would allow the hurricane’s strongest winds to spread out over a larger area, resulting in a damaging surge characteristic of a Cat 3 hurricane affecting a larger portion of the coast. The most devastating scenario for Tampa Bay painted by any of the model runs from 6Z (2 a.m. EDT) Monday was from the new HAFS-B model, which showed Milton hitting as a large Cat 3 with 115 mph (185 km/h) winds just north of Tampa Bay (Fig. 3). Such a storm would likely generate a storm surge in the bay in excess of 10 feet, causing over $10 billion in damage. The HAFS-B model outperformed all the other models for 3-, 4-, and 5-day forecasts last year. …
With the new 6Z Monday runs of the HWRF, HMON, HAFS-A, HAFS-B, COAMPS-TC, GFS, and European models, all painted variations of a dire scenario for Milton for Tampa Bay, showing a landfall just to the north of or over Tampa Bay. The only model showing a best-case scenario for them was the 0Z Monday run of the UKMET model, which depicted a landfall near Fort Myers, about 80 miles south of Tampa Bay.
