Tropical Storm — Coastal St. Johns, Florida

2019-09-04 · Coastal St. Johns, Florida

Event narrative

At 115 am on 9/4, the St. Augustine Pier reported a sustained wind of 44 mph with a gust to 52 mph. At 155 pm, a storm surge value of 3.16 ft MHHW datum was measured at the temporarily deployed USGS Tidal Gauge along the Tolomoto River near St. Augustine. Coastal flooding for this location begins around 1.6 ft MHHW. At 3 pm, the water level reached 2.52 ft MHHW on the Tolomoto River north of St. Augustine airport via a DEP Tide Gauge. Coast flooding occurs around 1.2 ft MHHW at this location. This was the highest sea levle rise since 3.61 ft MHHW during Hurricane Irma in 2017. There were some homes flooded in the Davis Shores neighborhood near St. Augustine. A new cut in the beach was formed near Summerhaven. There was overwash and beach erosion observed in Vilano Beach. Trees and branches were blown down within the St. Augustine city limits. The St. Augustine C-Man station recorded a peak sustained wind of 51 mph on 9/4 at 9 am with a peak gust of 62 mph on 9/4 at 8:58 am. The Weatherflow mesonet sensor at Cresent Beach Summerhouse measured a peak wind of 39 mph on 9/4 at 6:48 am and a peak gust of 58 mph on 9/4 at 108 am. The peak wind measured at the St. Augustine Airport was 38 mph on 9/4 at 1:46 am with a peak gust of 47 mph on 9/4 at 1:45 am. Storm total rainfall of 3.47 inches was measured about 6 miles SSW of Palm Valley and 3.31 inches about 2 miles S of Sawgrass.

Wider weather episode

Hurricane Dorian passed between 80-100 NM offshore of the local Atlantic Coast through the day on Sept. 4, 2019, as a Cat 2 storm on its closet approach. Ahead of Dorian, elevated King Tides and persistent onshore flow already raised water levels within the local estuaries by about 1-1.5 ft including the ICWW and St. Johns River basin. Total water rise (storm tide) associated with Dorian was up to 3.2 ft MHHW along the St. Johns county coast to about 1.5-2 ft MHHW within the St. Johns River basin. Heaviest rainfall was confined to a couple bands in St. Johns & Flagler counties. Wind damage was confined to the immediate coast and areas generally east of the I-95 corridor. There was damage to some beach structures including piers and boardwalks. Some homes flooded in Davis Shores of St. Augustine due to surge flooding & rainfall.

Source: NOAA Storm Events Database, event_id 853667. Narrative written by the NWS forecast office that issued the report.