Flooding Expected Along the Coast …

Tropical Storm conditions are expected to bring high winds, heavy rains and coastal flooding through much of the weekend.

INFORMATION ABOUT STORMS

WHAT IS A HURRICANE?

A hurricane is a type of tropical cyclone, which is a generic term for a low pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms and, in the Northern Hemisphere, a counterclockwise circulation of winds near the earth's surface. Tropical cyclones are classified as follows:

• Tropical Depression

An organized system of clouds and thunderstorms with a defined surface circulation and maximum sustained winds* of 38 mph (33 kt**) or less

• Tropical Storm

An organized system of strong thunderstorms with a defined surface circulation and maximum sustained winds of 39-73 mph (34-63 kt)

• Hurricane

An intense tropical weather system of strong thunderstorms with a well-defined surface circulation and maximum sustained winds of 74 mph (64 kt) or higher

WATCH vs. WARNING - KNOW THE DIFFERENCE

• TROPICAL STORM WATCH: An announcement that tropical storm conditions (sustained winds of 39 to 73 mph) are possible within the specified coastal area within 48 hours.

• TROPICAL STORM WARNING: An announcement that tropical storm conditions (sustained winds of 39 to 73 mph) are expected somewhere within the specified coastal area within 36 hours.

• HURRICANE WATCH: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are possible within the specified coastal area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 hours in advance of the anticipated onset of tropical-storm-force winds.

• HURRICANE WARNING: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are expected somewhere within the specified coastal area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds.

STORM SURGE

"The greatest potential for loss of life related to a hurricane is from the storm surge." 

Storm surge is simply water that is pushed toward the shore by the force of the winds swirling around the storm. This advancing surge combines with the normal tides to create the hurricane storm tide, which can increase the mean water level 15 feet or more. In addition, wind driven waves are superimposed on the storm tide. This rise in water level can cause severe flooding in coastal areas, particularly when the storm tide coincides with the normal high tides. Because much of the United States' densely populated Atlantic and Gulf Coast coastlines lie less than 10 feet above mean sea level, the danger from storm tides is tremendous.

The level of surge in a particular area is also determined by the slope of the continental shelf. A shallow slope off the coast will allow a greater surge to inundate coastal communities. Communities with a steeper continental shelf will not see as much surge inundation, although large breaking waves can still present major problems. Storm tides, waves, and currents in confined harbors severely damage ships, marinas, and pleasure boats.

The Delaware Emergency Management Agency (DEMA) reminds folks to make a plan, build a kit, and stay informed when disaster strikes. Follow @DelawareEMA on social media for tips to keep you and your loved ones safe during an emergency.

Additional information may be located at:

Delaware Emergency Management Agency - https://dema.delaware.gov/emergencyPrep/index.shtml

Make a Plan - https://preparede.org/make-a-plan

Build a Kit - https://preparede.org/build-a-kit

Stay Informed - https://preparede.org/stay-informed

Resources - https://preparede.org/resources

Additional weather information forecast information:

• https://www.wrde.com/news/severe-flooding-expected-along-the-coast/article_1dc4b378-591c-11ee-a531-57521391c8b1.html

• https://www.wboc.com/weather/tropical-storm-conditions-develop-friday-afternoon/article_cd15f7ac-5916-11ee-b65a-2f88e4b1af12.html

• https://www.delawareonline.com/story/weather/2023/09/22/tropical-storm-ophelia-2023-coastal-flood-warning-advised-delaware-east-coast/70928757007/

• https://www.wrde.com/news/potential-tropical-cyclone-16-what-to-expect-weekend-timeline-for-coastal-delmarva/article_14ea4a8c-594a-11ee-994a-3fdeda82836d.html