I. Basic Coastal Definitions
From SCOOP Wiki
Read through these definitions before going on to the hurricane simulations. They will help you to understand what you are going to simulate and see.
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Approach Angle
Approach angle is the direction a hurricane advances toward the shore. If a hurricane is advancing directly towards the shore (perpendicular to the shore), the storm is approaching at a 0 degree angle. If a storm is approaching at an angle to the shore, the approach angle will be a negative or positive number between 0 and 90. If a hurricane is moving parallel to the shore, the hurricane is not moving toward the shore, so there will be no approach angle.
Bottom Slope
Bottom slope is defined as the slope of the sea floor as it approaches the shoreline. It is a ratio of the vertical change over a given horizontal distance. A typical slope of a steeper sea floor would be 1/100 or even 1/50, whereas a more gradually changing sea floor would have a much smaller slope of about 1/1000. The offshore slope can greatly affect the amount of surge from a storm.
Categories
Hurricanes are rated according to the Saffir-Simpson Scale, which ranges from Category 1 (less extreme) to Category 5 (most extreme). A major hurricane is defined as Category 3 or higher.
Below are definitions of each category. The scale’s determining factor is the wind speed. Based on the hurricane’s category, predictions can be made about the damage and flooding expected due to a hurricane landfall. Also included are pictures of Hurricane Katrina when it was a Category 1 through Category 5 storm. Notice Category 5 storms are much more organized and damaging than a Category 1 storm.
Category 1: minimal:
Wind Speed: 64-82 kt (74-95 mph);
Storm Surge: 4-5 ft above normal;
Scarce evacuation
No real damage to structures; Damage primarily to unanchored mobile homes, shrubs, trees, some road signs; Some coastal road flooding and minor pier damage
Category 2: moderate:
Wind Speed: 83-95 kt (96-110 mph);
Storm Surge: 6-8 ft above normal;
Some of the shoreline evacuated
Damage to parts buildings (roofs, doors, and windows); Considerable damage to mobile homes, some road signs, piers, trees and shrubs; Coastal and low-lying escape routes flooded 2-4 hours before landfall; Marinas flooded
Category 3: extensive:
Wind Speed: 93-113 kt (111-130 mph);
Storm Surge: 9-12 ft above normal;
Evacuation of low-lying residences within several blocks of the shoreline may be required
Some structural damage to small residences and utility buildings; Damage to shrubbery and trees with large trees blown down; Mobile homes and poorly constructed signs destroyed; Coastal and low-lying escape routes flooded 3-5 hours before landfall; Flooding near the coasts can destroy smaller structures and floating debris can damage larger structures
Category 4: extreme:
Wind Speed: 114-135 kt (131-155 mph);
Storm Surge: 13-18 ft above normal;
Low land should evacuate as far inland as 6 miles
Some complete roof structure failures on small residences; Extensive damage to doors, windows, and lower floors of structures near the shore; Shrubs, trees, and all signs are blown down; Complete destruction of mobile homes; Low-lying escape routes flooded 3-5 hours before landfall; Flooding near the coasts can destroy smaller structures and floating debris can damage larger structures
Category 5: catastrophic:
Wind Speed: greater than 135 kt (155 mph);
Storm Surge: Greater than 18 ft above normal;
Massive evacuation of residential areas on low ground within 5-10 miles of shoreline
Complete roof failure on many residences and industrial buildings; Some complete building failures with small utility buildings blown over or away; Severe and extensive damage to doors, windows, and all lower floors of structures near the shoreline; Most shrubs, trees, and signs blown down; Complete destruction of mobile homes; Low-lying escape routes flooded 3-5 hours before landfall
Domain
Domain refers to the region where a simulation is generated. In the case of the SCOOP simulation, the domain choices are no bay, large mouth bay, and small mouth bay. A bay is a partially enclosed body of water, usually with an opening to the open ocean. The mouth is the opening that leads into or out of the bay. No bay means there is only a shore and no body of water other than the ocean. In an actual domain, a mouth into a bay could be a variety of sizes. In this case, there are two choices, either a large opening or a small opening. During a hurricane, the size of the mouth can greatly affect water flow and flooding.
Forecast Times
The National Hurricane Center (NHC) and the local National Weather Service Forecast Office issue hurricane forecast products. Most of these are issued 4 times daily, every 6 hours. Tropical Weather Outlook is issued every day during hurricane season (June 1 through November 30). This gives a general overview of what is going on in the tropics. During the time when a hurricane is present, Public Advisories are given every 6 hours to describe the storm and its predicted hazards. Intermediate Public Advisories are issued every 3 hours when a hurricane watch or warning is in effect or every 2 hours when land-based radars have identified a defined storm center. Forecasts and Advisories are issued every 6 hours or as needed to provide forecasts of the wind fields around the storm. Other reports and forecasts are also issued; some more frequent then others when there is a hurricane. In the Hurricane Charley simulation, you can choose between reports that are 6 hours apart for the days that are relevant to the domain we are interested in.
Forward Speed
Forward speed defines how quickly a storm is moving over land or water, as opposed to internal wind speed which determines intensity. Storms move slowly in the tropics, usually 13 kts (15 mph) or less. Some storms even seem stationary for short periods of time. As the storm moves further north away from the Equator, forward speed usually increases. In extreme cases, some storms have forward speeds that exceed 43 kts (50 mph).
Landfall Location
The landfall location is the point at which the center (area with the lowest pressure and winds) of a tropical cyclone intersects the shoreline. A strike occurs when the hurricane's "strike circle" hits land (see picture). The strike circle is 125 n mi in diameter, centered 12.5 n mi to the right and 50 n mi to the left. A direct hit is when the storm gets extremely close to a particular location. For any location on the left side of the storm, this occurs when the storm passes a distance equal to the RMW. For any location on the right side of the storm, it is double that distance. An indirect hit occurs when the location experiences above normal tides and storm force winds but the storm does not directly hit.
Radius to Maximum Winds
The radius to maximum winds (RMW) is the distance from the center point of a tropical cyclone to the location with the maximum winds. When hurricanes are well developed, this location can typically be found at the inner edge of the eyewall.
Tides
Phases
A. 
B. 
C. 
D. 
Tides are the rising and falling of the ocean surfaces caused by the gravitational pull of the Sun and the Moon on large bodies of water. This constant rising and falling closely resembles a sinusoidal wave (see below pictures). High tide (A) occurs when the water level is at a maximum. As the water surface falls, an ebb tide (B) occurs until the minimum water level, or low tide (C), is reached. Then, as the water level starts to rise again, a flood tide (D) occurs.
Amplitude
Tidal amplitude is defined as half the distance between high and low tide. Large tidal amplitudes can be a cause for great destruction, especially when coupled with storm surge. For example, greater changes in tides lead to larger velocities and amounts of water. This can be quite a problem for smaller inlets because a large amount of water needs to go through a small area.
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