Saturday, August 27, 2011

Hurricane Irene Advisory #29A

000
WTNT34 KNHC 271803
TCPAT4

BULLETIN
HURRICANE IRENE INTERMEDIATE ADVISORY NUMBER 29A...CORRECTED
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
200 PM EDT SAT AUG 27 2011

CORRECTED FORWARD SPEED IN THE SUMMARY SECTION

...IRENE MOVING ACROSS EASTERN NORTH CAROLINA...


SUMMARY OF 200 PM EDT...1800 UTC...INFORMATION
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LOCATION...35.5N 76.3W
ABOUT 45 MI...70 KM WNW OF CAPE HATTERAS NORTH CAROLINA
ABOUT 95 MI...155 KM S OF NORFOLK VIRGINIA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NNE OR 15 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...950 MB...28.05 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

ENVIRONMENT CANADA HAS ISSUED A TROPICAL STORM WARNING FROM THE UNITED STATES BORDER NORTHEASTWARD TO FORT LAWRENCE INCLUDING GRAND MANAN...AND FOR THE SOUTH COAST OF NOVA SCOTIA FROM FORT LAWRENCE TO PORTERS LAKE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* LITTLE RIVER INLET NORTH CAROLINA NORTHWARD TO SAGAMORE BEACH MASSACHUSETTS...INCLUDING THE PAMLICO...ALBEMARLE...AND CURRITUCK SOUNDS...DELAWARE BAY...CHESAPEAKE BAY SOUTH OF DRUM POINT...NEW YORK CITY...LONG ISLAND...LONG ISLAND SOUND...COASTAL CONNECTICUT AND RHODE ISLAND...BLOCK ISLAND...MARTHAS VINEYARD AND NANTUCKET

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* CHESAPEAKE BAY FROM DRUM POINT NORTHWARD AND THE TIDAL POTOMAC
* NORTH OF SAGAMORE BEACH TO EASTPORT MAINE
* UNITED STATES/CANADA BORDER NORTHEASTWARD TO FORT LAWRENCE INCLUDING GRAND MANAN
* SOUTH COAST OF NOVA SCOTIA FROM FORT LAWRENCE TO PORTERS LAKE

INTERESTS ELSEWHERE IN EASTERN CANADA SHOULD MONITOR THE PROGRESS OF IRENE.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA IN THE UNITED STATES...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. FOR STORM INFORMATION SPECIFIC TO YOUR AREA OUTSIDE THE UNITED STATES...PLEASE MONITOR PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 200 PM EDT...1800 UTC...THE CENTER OF HURRICANE IRENE WAS LOCATED NEAR LATITUDE 35.5 NORTH...LONGITUDE 76.3 WEST. IRENE IS MOVING TOWARD THE NORTH-NORTHEAST NEAR 13 MPH...20 KM/H. A NORTH-NORTHEASTWARD MOTION AT A SLIGHTLY FASTER FORWARD SPEED IS EXPECTED DURING THE NEXT DAY OR SO. ON THE FORECAST TRACK...THE CENTER OF IRENE WILL MOVE ACROSS NORTHEASTERN NORTH CAROLINA THIS AFTERNOON. THE HURRICANE IS FORECAST TO MOVE NEAR OR OVER THE MID-ATLANTIC COAST TONIGHT AND MOVE OVER SOUTHERN NEW ENGLAND ON SUNDAY.

MAXIMUM SUSTAINED WINDS REMAIN NEAR 85 MPH...140 KM/H...WITH HIGHER GUSTS. SLIGHT WEAKENING IS FORECAST AS IRENE CROSSES EASTERN NORTH CAROLINA...BUT IRENE IS FORECAST TO REMAIN AT OR NEAR HURRICANE STRENGTH AS IT MOVES NEAR OR OVER THE MID-ATLANTIC STATES AND APPROACHES NEW ENGLAND.

IRENE IS A LARGE TROPICAL CYCLONE. HURRICANE-FORCE WINDS EXTEND OUTWARD UP TO 90 MILES...150 KM...FROM THE CENTER...AND TROPICAL- STORM-FORCE WINDS EXTEND OUTWARD UP TO 260 MILES...415 KM. A WIND GUST TO 78 MPH WAS RECENTLY MEASURED AT CAPE HATTERAS NORTH CAROLINA. A WIND GUST TO 67 MPH WAS RECENTLY REPORTED AT LANGLEY AIR FORCE BASE IN SOUTHEASTERN VIRGINIA.

THE LATEST MINIMUM PRESSURE REPORTED FROM A DROPSONDE RELEASED BY AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT WAS 950 MB...28.05 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL-STORM-FORCE WINDS WILL SPREAD NORTHWARD ALONG THE MID-ATLANTIC COAST TODAY WITH HURRICANE CONDITIONS EXPECTED BY TONIGHT. TROPICAL STORM CONDITIONS ARE EXPECTED TO REACH SOUTHERN NEW ENGLAND LATE THIS EVENING WITH HURRICANE CONDITIONS EXPECTED BY SUNDAY MORNING. WINDS AFFECTING THE UPPER FLOORS OF HIGH-RISE BUILDINGS WILL BE SIGNIFICANTLY STRONGER THAN THOSE NEAR GROUND-LEVEL.

STORM SURGE...AN EXTREMELY DANGEROUS STORM TIDE WILL RAISE WATER LEVELS BY AS MUCH AS 5 TO 9 FEET ABOVE GROUND LEVEL IN THE HURRICANE WARNING AREA IN NORTH CAROLINA...INCLUDING THE ALBEMARLE AND PAMLICO SOUNDS. STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 4 TO 8 FEET ABOVE GROUND LEVEL WITHIN THE HURRICANE WARNING AREA FROM THE NORTH CAROLINA/VIRGINIA BORDER NORTHWARD TO CAPE COD INCLUDING SOUTHERN PORTIONS OF THE CHESAPEAKE BAY AND ITS TRIBUTARIES. NEAR THE COAST...THE SURGE WILL BE ACCOMPANIED BY LARGE...DESTRUCTIVE...AND LIFE-THREATENING WAVES. HIGHER THAN NORMAL ASTRONOMICAL TIDES ARE OCCURRING THIS WEEKEND. COASTAL AND RIVER FLOODING WILL BE HIGHEST IN AREAS WHERE THE PEAK SURGE OCCURS AROUND THE TIME OF HIGH TIDE. STORM TIDE AND SURGE VALUES ARE VERY LOCATION-SPECIFIC...AND USERS ARE URGED TO CONSULT PRODUCTS ISSUED BY THEIR LOCAL NATIONAL WEATHER SERVICE OFFICES.

RAINFALL...IRENE IS EXPECTED TO PRODUCE RAINFALL ACCUMULATIONS OF 6 TO 12 INCHES...WITH ISOLATED MAXIMUM AMOUNTS OF 18 INCHES...FROM EASTERN NORTH CAROLINA NORTHWARD THROUGH THE MID-ATLANTIC STATES INTO EASTERN NEW YORK AND INTERIOR NEW ENGLAND. THESE RAINS... COMBINED WITH HEAVY RAINS OVER THE PAST FEW WEEKS...COULD CAUSE WIDESPREAD FLOODING...LIFE-THREATENING FLASH FLOODS...AND SIGNIFICANT UPROOTING OF TREES DUE TO RAIN-SOFTENED GROUNDS.

SURF...LARGE SWELLS GENERATED BY IRENE ARE AFFECTING MUCH OF THE COAST OF THE UNITED STATES. THESE SWELLS WILL CAUSE LIFE-THREATENING SURF AND RIP CURRENT CONDITIONS.

TORNADOES...ISOLATED TORNADOES ARE POSSIBLE OVER SOUTHEASTERN VIRGINIA...EASTERN MARYLAND...DELAWARE...AND SOUTHERN NEW JERSEY THROUGH THIS EVENING.


NEXT ADVISORY
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NEXT COMPLETE ADVISORY...500 PM EDT.

$$
FORECASTER BROWN