The strong winds, gusting up to 50 mph from the south, arrived ahead of a drenching rainstorm that unloaded widespread totals of one to two inches. The flooding was mostly the result of the wind shoving water up the bay, but rainfall added to the inundation.
Baltimore’s tide gauge showed a peak water level of 4.24 feet, the highest since Sept. 19, 2003, when Hurricane Isabel elevated the tide to 8.15 feet. Thursday’s water level was the 11th highest on record, and equated to tides 2.5 to 3 feet above normal and up to one foot of inundation above normally dry ground.
The Fox television affiliate in Baltimore reported that “a lot of debris was left behind after high water” at the Inner Harbor and that residents of Fells Point were “encouraged to park for free” at an elevated garage due to the high tides.
The tide gauge in Annapolis, along the Severn River, showed the water level peaked at 3.72 feet, more than a foot above flood stage (2.6 feet), constituting “moderate flooding” and “one to two feet of inundation above ground level,” according to the National Weather Service. The 3.72-foot crest marked the highest water level since reaching 4.15 feet on October 12, 2019 and 4.08 feet on Oct. 4, 2014. The water level ranks among the top 15 highest on record since at least the 1930s.
The Annapolis Office of Emergency Management posted on Facebook that several roads were closed Thursday, as well as the Eastport Bridge. Annapolis’s Capital Gazette reported businesses in affected areas were mostly shuttered because of the coronavirus. “Water could be seen pooling at the door of Pip’s Dock Street [Dogs], which has been closed since last month due to the pandemic,” the newspaper wrote.
By midmorning Friday, roads had been reopened in Annapolis as waters receded.
The National Weather Service had issued coastal flood warnings along the western shores of the Chesapeake Bay on Thursday and coastal flood advisories for the Tidal Potomac.
The warnings for the bay were discontinued Friday, but a coastal flood advisory lingered for the section of the Tidal Potomac running through the District through 6 p.m. for “up to one half foot of inundation above ground level.” Water levels from Georgetown to Old Town Alexandria have been elevated since Thursday and caused some minor flooding, but they were not as historically high as those along the Chesapeake Bay.
Because of rising seas due to climate change, the frequency of coastal flooding has increased dramatically in the Mid-Atlantic in recent decades. From 2000 to 2015, the incidence of high-tide flooding doubled from an average of three days per year to six, according to a National Oceanic and Atmospheric Administration report.
The report reached the startling conclusion that by the end of this century “high tide flooding will occur ‘every other day’ (182 days/year) or more often,” even under an “intermediate low scenario” as the climate warms and seas rise.
Here are some more images of Thursday’s flooding in Annapolis: