Hermine Produced the 5th-Highest Recorded Water Level at Cedar Key, Florida

Hurricane Hermine generated a widespread storm surge along Florida's West Coast, north of the Tampa/ St. Pete metro area. Although Hermine made landfall as a category-1 hurricane, it's relatively large size contributed to the high storm surge. As it approached the coast, 50-kt winds (57 mph) extended to the southeast for 120 miles.

Also, the region in which it struck is very efficient for generating large surges. The concave shape of Florida's Big Bend area, and the shallow bathymetry, or water depth, serve to enhance water levels.

The Weather Channel broadcast Hermine's storm surge inundation live on Facebook during the afternoon and evening on Thu Sep 1.

Water levels were particularly high to the east and south of Apalachee Bay, in areas like Cedar Key. The graph below plots Hermine's water level within a broader context of storm surge events at Cedar Key.

Hermine produced the 5th-highest recorded water level in Cedar Key, Florida.

Rapid summary of high water at Cedar Key:

The water level at Cedar Key reached 7.64 ft above the NAVD88 datum on Fri Sep 2 at 1:36AM EDT. This is:

​The 5th highest storm tide level out of 34 surges on record

The 4th highest storm tide level from a tropical system

​The highest recorded water level since 1993 (23 years)

Note: The storm surge level (actual - predicted level) exceeded 7.5 ft at Cedar Key

All eyes now turn to the Mid-Atlantic Coast, where both the European and GFS models predict that Hermine, or more likely an extra-tropical system, will park near the coast and possibly turn towards land over Labor Day weekend.

The GFS model run, hosted on the Tropical Tidbits website, displays a nearly stationary area of low pressure off the Delmarva Peninsula on Labor Day. 

This forecast is of great concern for coastal areas from Virginia through Massachusetts, as storm surge and waves will have ample time to build if this forecast holds.

Check back over the weekend, as I hope to provide some storm surge analysis for the Mid-Atlantic region.