Public Information Statement
Issued by NWS Portland, ME

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Public Information Statement
National Weather Service Gray ME
0600 AM EDT Tue Jul 16 2019

The National Weather Service has declared the week of July 15th
through 19th HURRICANE SAFETY AWARENESS WEEK in New England.
This is the second in a series of five public information
statements to be issued by the National Weather Service Office
in Gray containing information on hurricanes and hurricane safety.

HURRICANE WINDS AND TORNADOES

Both hurricanes and tropical storms produce dangerous winds that
can produce life-threatening conditions for anyone who is caught
in them. Hurricane force winds can easily destroy poorly
constructed buildings and mobile homes. Debris such as signs,
roofing material, and small items left outside can become flying
missiles during hurricanes. Extensive damage caused by falling
trees can lead to lengthy power and phone outages.

Tropical circulations are classified based on the following wind
speed criteria.

          Wind Speed             Name
       Less than 39 mph       Tropical Depression
       39 to 73 mph           Tropical Storm
       74 mph or greater      Hurricane

Hurricanes are further divided into 5 categories based on the
destructive power of their winds. The scale used in hurricane
classification is called the Saffir-Simpson Scale. Below is a
list of the Saffir-Simpson Scale, the typical damage that occurs
with storms of each category, and examples of each category of
storm (at landfall).

SAFFIR-SIMPSON HURRICANE SCALE
CategoryDefinition-Effects

   1    Winds: 74-95 mph (64-82 kt)
          No real damage to well-constructed buildings. Damage
          primarily to poorly constructed buildings and
          unanchored mobile homes, shrubbery, and trees. Also,
          some coastal flooding and minor pier damage is
          possible.

          Examples: Irene (1999) and Allison (1995)

   2 Winds: 96-110 mph (83-95 kt)
          Some damage to building roofs, doors, and windows.
          Considerable damage to vegetation, mobile homes, etc.
          Flooding damages piers and small craft in unprotected
          moorings may break their moorings.

          Examples: Bonnie (1998), Georges (1998) and Gloria
          (1985)

   3 Winds: 111-129 mph (96-112 kt)
          Some structural damage to small residences and utility
          buildings, with a minor amount of curtain-wall
          failures. Mobile homes are destroyed. Flooding near
          the coast destroys smaller structures with larger
          structures damaged by floating debris. Terrain may be
          flooded well inland.

          Examples: Katrina (2005), Fran (1996), Opal (1995),
          Alicia (1983) and Betsy (1965)

   4      Winds: 130-156 mph (113-136 kt)
          More extensive curtain-wall failures with some
          complete roof structure failure on small residences.
          Major erosion of beach areas. Terrain may be flooded
          well inland.

          Examples: Hugo (1989) and Donna (1960)

   5      Winds: 157+ mph (137+ kt)
          Complete roof failure on many residences and
          industrial buildings. Some complete building failures
          with small utility buildings blown over or away.
          Flooding causes major damage to lower floors of all
          structures near the shoreline. Massive evacuation of
          residential areas may be required.

          Examples: Andrew (1992), Camille (1969) and
          Labor Day-Florida Keys (1935)

Hurricanes can also produce tornadoes that add to the storm`s
destructive power. Tornadoes are most likely to occur to the
right side of the hurricane track, however, they can also
form in the rain bands, well away from the center of the
hurricane. Studies have shown that more than half of
land-falling hurricanes produce at least one tornado. In
general though, tornadoes associated with hurricanes are less
intense than those that occur in the Great Plains. Nonetheless,
the effects of tornadoes, added to the larger area of
hurricane force winds, can produce substantial damage.
Fortunately, hurricane-spawned tornadoes are infrequent in
northern New England.

QUESTION OF THE DAY: How often do we get hurricanes of each
category in Maine and New Hampshire?

The National Hurricane Center estimates "return periods" for
the various categories of hurricanes for locations along the
East and Gulf Coasts. In this determination, the likelihood
of the center of a hurricane passing within 75 miles of a
location is estimated. However, because northern New England
does not have many strong hurricanes, it is difficult to
determine the frequency of the stronger hurricanes.

Category       Return Period
               NH and SW ME
   1-2          30-50 years
   3-5         120-300 years

FACT FOR THE DAY: The strongest winds in a hurricane usually
occur on the right side of the track. If a hurricane makes
landfall on the northern New England coast, the strongest
winds will be to the east of the center of the storm. In
contrast, most of the precipitation falls on the left side of
the storm track. Hurricane Gloria, which made landfall over
Long Island and southern Connecticut and traveled west of
Portland, produced wind gusts of 70 mph in Portland, but
produced only 0.41 inches of rainfall in the city.

Here`s a list of the other topics covered in statements issued
this week:

Monday - Tropical Cyclones, Tropical Storms, and
         Hurricanes--The Basics
Wednesday - Storm Surge and Marine Safety
Thursday - Inland Flooding
Friday - The Forecast Process--Statements, Watches,
         and Warnings

For additional information about hurricanes and hurricane
safety, visit the National Hurricane Center`s web site at:

                http://www.nhc.noaa.gov/

$$

Watson
National Weather Service
Gray...Maine
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