509  
NOUS41 KGYX 171001  
PNSGYX  
 
PUBLIC INFORMATION STATEMENT  
NATIONAL WEATHER SERVICE GRAY ME  
0600 AM EDT WED JUL 17 2019  
 
THE NATIONAL WEATHER SERVICE HAS DECLARED THE WEEK OF JULY 15TH  
THROUGH 19TH HURRICANE SAFETY AWARENESS WEEK IN NEW ENGLAND.  
THIS IS THE THIRD IN A SERIES OF FIVE PUBLIC INFORMATION  
STATEMENTS TO BE ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE  
IN GRAYCONTAINING INFORMATION ON HURRICANES AND HURRICANE SAFETY.  
 
STORM SURGE, WAVES, AND MARINE SAFETY  
 
THE STORM SURGE IS A LARGE DOME OF WATER THAT IS PUSHED TOWARD  
THE SHORE BY THE FORCE OF THE WINDS CIRCULATING 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. THE GREATEST STORM SURGE GENERALLY OCCURS JUST  
TO THE RIGHT OF THE STORM TRACK, WHERE THE STRONGEST WINDS OF  
THE STORM ARE BLOWING ONSHORE, PERPENDICULAR TO THE COAST. IN  
ADDITION TO THE SURGE, WIND DRIVEN WAVES IN THAT AREA CAN ALSO  
CAUSE CONSIDERABLE DAMAGE TO STRUCTURES. THIS RISE IN WATER LEVEL  
DUE TO THE SURGE CAN RESULT IN SEVERE FLOODING IN COASTAL AREAS,  
PARTICULARLY WHEN THE STORM SURGE COINCIDES WITH THE NORMAL HIGH  
TIDES. FOR AREAS OF THE COAST LESS THAN 10 FEET ABOVE MEAN SEA  
LEVEL, THE DANGER FROM STORM SURGE CAN BE TREMENDOUS.  
 
ALONG THE NEW HAMPSHIRE AND MAINE COAST, THE GREATEST THREAT OF  
DAMAGE FROM STORM SURGE LIES IN THE BEACH AREAS SOUTH OF PORTLAND  
AND PENOBSCOT BAY.  
 
IN ADDITION TO THE SPEED AND INTENSITY OF THE HURRICANE, THE LEVEL  
OF SURGE IN A PARTICULAR AREA IS ALSO DETERMINED BY THE SLOPE OF  
THE UNDERWATER TOPOGRAPHY AND THE SHAPE OF THE COAST LINE. A  
SHALLOW SLOPE AND THE FUNNELING EFFECTS OF A BAY WILL CONTRIBUTE  
TO A GREATER SURGE. AREAS WITH A STEEPER CONTINENTAL SHELF WILL  
NOT SEE AS MUCH SURGE, ALTHOUGH LARGE BREAKING WAVES CAN STILL  
PRESENT MAJOR PROBLEMS. STORM TIDES, WAVES, AND CURRENTS IN  
CONFINED HARBORS CAN SEVERELY DAMAGE SHIPS, MARINAS, AND  
PLEASURE BOATS.  
 
IN NORTHERN NEW ENGLAND, THE GREATEST FACTOR IN DETERMINING THE  
EFFECTS OF A STORM SURGE IS THE TIMING OF THE SURGE WITH RESPECT  
TO THE ASTRONOMICAL TIDES. IF THE STORM SURGE HITS AT THE TIME OF  
LOW TIDE, LITTLE IF ANY COASTAL FLOODING WILL OCCUR. IF, HOWEVER,  
THE SURGE HITS AT HIGH TIDE, CONSIDERABLE COASTAL FLOODING, BEACH  
EROSION, AND OTHER DAMAGE IS POSSIBLE. UNFORTUNATELY, THE EXACT  
TIMING OF LANDFALL IN NORTHERN NEW ENGLAND IS OFTEN DIFFICULT TO  
PREDICT VERY FAR IN ADVANCE, SO PLANS SHOULD BE MADE BASED ON THE  
POSSIBILITY THE SURGE COULD STRIKE AT HIGH TIDE.  
 
WAVE AND CURRENT ACTION ASSOCIATED WITH THE TIDE ALSO CAUSES  
EXTENSIVE DAMAGE. WATER WEIGHS APPROXIMATELY 1700 POUNDS PER  
CUBIC YARD, AND EXTENDED POUNDING BY FREQUENT WAVES CAN DEMOLISH  
ANY STRUCTURE NOT SPECIFICALLY DESIGNED TO WITHSTAND SUCH FORCES.  
WAVES GENERATED FROM DISTANT OR APPROACHING STORMS CAN ALSO PRESENT  
A HAZARD TO THOSE WHO ARE NEAR THE OCEAN. STRONG RIP CURRENTS CAN  
CARRY EVEN STRONG SWIMMERS OUT TO SEA, AND UNEXPECTED LARGE WAVES  
CAN WASH PEOPLE FROM ROCKS.  
 
HURRICANES HAVE BEEN THE CAUSE OF MANY MARITIME DISASTERS AND,  
UNFORTUNATELY, THERE IS NO SINGLE RULE OF THUMB THAT CAN BE USED BY  
MARINERS TO ENSURE SAFE SEPARATION FROM A HURRICANE AT SEA. IN ORDER  
TO MINIMIZE RISK, MARINERS SHOULD ALLOW FOR A LARGE MARGIN OF ERROR  
IN THE HURRICANE TRACK AND INTENSITY FORECASTS. TODAY, EVEN AS OUR  
UNDERSTANDING OF AND ABILITY TO FORECAST HURRICANES INCREASES,  
THERE IS STILL CONSIDERABLE ERROR IN FORECASTING THE MOVEMENT AND  
INTENSITY OF THESE SYSTEMS.  
 
AVERAGE ERRORS IN THE HURRICANE TRACK FORECAST INCREASE CONSIDERABLY  
AS THE FORECAST PROJECTION INCREASES. THE FOLLOWING LIST GIVES  
AVERAGE ERRORS OF HURRICANE FORECASTS FOR THE 5-YEAR PERIOD FROM 2014  
TO 2018. NOTE THAT ERRORS FOR STORMS IN NORTHERN NEW ENGLAND ARE  
LIKELY GREATER THAN THESE "AVERAGE" VALUES DUE TO THE ACCELERATION  
THAT OFTEN OCCURS SOUTH OF NEW ENGLAND AND DUE TO THE COMPARATIVELY  
FAST MOVEMENT OF THE STORMS IN NEW ENGLAND WATERS.  
 
FORECAST PROJECTION AVERAGE ERROR  
12 HOURS 26 N MI  
24 HOURS 41 N MI  
48 HOURS 68 N MI  
72 HOURS 102 N MI  
96 HOURS 151 N MI  
120 HOURS 198 N MI  
 
FOR THOSE WITH BOATS, IT'S IMPORTANT TO PLAN AHEAD. KNOW EXACTLY WHAT  
YOU NEED TO DO AND HOW LONG IT WILL TAKE YOU TO ACCOMPLISH THE  
NECESSARY TASKS. KEEP IN MIND THAT OTHERS WILL ALSO BE TAKING  
PREPARATORY ACTIONS TOO, SO YOU SHOULD LEAVE YOURSELF ADDITIONAL  
TIME.  
 
IF YOU PLAN TO LEAVE YOUR BOAT IN THE WATER, CONSIDER THE POSSIBLE  
EFFECTS OF THE STORM TIDE AND WAVES. MAKE SURE YOUR ANCHOR IS  
SUFFICIENTTO HOLD THE BOAT, AND HAVE ENOUGH ANCHOR LINE TO ACCOUNT  
FOR THE STORM TIDE. SECURE OR REMOVE ALL NON-PERMANENT EQUIPMENT FROM  
THE DECK. NEVER TRY TO RIDE OUT THE STORM ON YOUR BOAT; YOU WILL  
ENDANGER YOUR LIFE AND POSSIBLY THE LIVES OF RESCUERS.  
 
IF YOU ARE ABLE TO PUT YOUR BOAT ON A TRAILER, GET IT OUT OF THE  
WATER EARLY. IF YOU WAIT TOO LONG, YOU MAY BE IN A LONG LINE. IF  
POSSIBLE, STORE YOUR BOAT INSIDE A GARAGE. HOWEVER, IF YOU LEAVE  
YOUR BOAT OUTSIDE, PUT IT IN A SHELTERED LOCATION, AND SECURE IT TO  
STURDY OBJECTS SUCH AS LARGE TREES.  
 
QUESTION OF THE DAY: WHAT WAS THE GREATEST LOSS OF LIFE ASSOCIATED  
WITH ANY STORM SURGE IN THE UNITED STATES?  
 
WHILE NOT ALL DETAILS ARE KNOWN, THE CATEGORY 4, GALVESTON, TEXAS  
HURRICANE OF SEPTEMBER 8, 1900, CAUSED THE GREATEST LOSS OF LIFE  
FROM A STORM SURGE. NOT ONLY WAS IT THE GREATEST LOSS OF LIFE FROM  
A STORM SURGE, IT WAS ALSO THE GREATEST LOSS OF LIFE IN THE UNITED  
STATES ASSOCIATED WITH ANY WEATHER-RELATED DISASTER. THE HURRICANE  
CREATED AN 8 TO 15 FOOT SURGE THAT INUNDATED ALL OF GALVESTON ISLAND,  
AS WELL AS OTHER PORTIONS OF THE NEARBY TEXAS COAST. THIS SURGE WAS  
LARGELY RESPONSIBLE FOR THE ESTIMATED 6,000 TO 12,000 DEATHS  
ATTRIBUTED TO THE STORM. THE DAMAGE TO PROPERTY WAS ESTIMATED AT  
$30 MILLION.  
 
FORTUNATELY, SATELLITES, COMPUTERS, ADVANCED SENSING AND PREDICTION  
TECHNIQUES, AND BETTER COMMUNICATION SYSTEMS ALLOW METEOROLOGISTS TO  
BETTER PREDICT AND WARN THE PUBLIC OF IMPENDING HURRICANES.  
 
OTHER NOTABLE SURGES OCCURRED WITH HURRICANE ANDREW (17 FEET),  
HURRICANE HUGO (20 FT), AND HURRICANE CAMILLE (24.6 FEET). THE 1938  
HURRICANE THAT AFFECTED NEW ENGLAND CAUSED A 10 TO 12 FT SURGE IN  
NARRAGANSETT AND BUZZARDS BAYS.  
 
FACT FOR THE DAY: THE LOCATION WITH THE GREATEST POTENTIAL FOR STORM  
SURGE ALONG THE NORTHERN NEW ENGLAND COAST IS THE PENOBSCOT RIVER  
NEAR BANGOR, MAINE. COMPUTER MODEL ESTIMATES INDICATE THAT THE  
FUNNELING EFFECT OF THE PENOBSCOT BAY AND RIVER COULD LEAD TO A  
23 FOOT TIDE FOR A CATEGORY 3 HURRICANE MOVING NORTH AT 40 MPH.  
 
HERE'S A LIST OF THE OTHER TOPICS COVERED IN STATEMENTS ISSUED  
THIS WEEK:  
 
MONDAY - TROPICAL CYCLONES, TROPICAL STORMS, AND  
HURRICANES--THE BASICS  
TUESDAY - HURRICANE WINDS AND TORNADOES  
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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