Much of the damage inflicted in the state was caused by an unusually strong storm surge, which inundated the coastal and low-lying areas of Florida. Although the strongest storm surge was positioned north of the eye, away from the more densely populated regions of Greater Miami, an abnormally high storm tide still prevailed and caused extensive damage along the southern coast of the peninsula. Northerly winds well in advance of Betsy's landfall forced water from Florida Bay onto the Florida Keys, and the resulting damage was then further exacerbated when southerly winds during and after the hurricane's approach forced water from the Atlantic onto the isolated Keys. Though storm surge was estimated to have peaked along the coast of North Key Largo at , a measurement of in Tavernier was the highest measured total. However, a high water mark of on a highway west of Sugarloaf Key indicated that such estimations in North Key Largo were valid. The strong storm surge caused severe beach erosion, mostly to areas south of Clearwater on the state's western coast while Betsy was traversing the Gulf of Mexico. In Fort Pierce, the waves washed away up to of beach.