Quantcast wmbb.com - Tropical Storm Hanna - Update 4:00 pm CDT
Click Here

--- Advertisement ---

Tropical Storm Hanna - Update 4:00 pm CDT
09/05/08 - 03:00 PM
National Hurricane Center
 RSS Feed
Miami, Fla

Public Advisory:

HANNA STILL JUST BELOW HURRICANE STRENGTH… TROPICAL STORM WATCH EXTENDED NORTHWARD… A TROPICAL STORM WARNING IS NOW IN EFFECT FROM ALTAMAHA SOUND GEORGIA NORTHWARD ALONG THE ATLANTIC COAST TO SANDY HOOK NEW JERSEY… INCLUDING PAMLICO AND ALBEMARLE SOUNDS… INCLUDING ALL OF CHESAPEAKE BAY… .THE TIDAL POTOMAC… WASHINGTON D.C… AND THE DELAWARE BAY. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA WITHIN THE NEXT 24 HOURS.

THE HURRICANE WATCH REMAINS IN EFFECT FROM NORTH OF EDISTO BEACH SOUTH CAROLINA TO CURRITUCK BEACH LIGHT NORTH CAROLINA… INCLUDING PAMLICO SOUND. HURRICANE WARNINGS MAY BE REQUIRED FOR PORTIONS OF THIS AREA TONIGHT.

AT 5 PM EDT… 2100 UTC… THE TROPICAL STORM WATCH IS EXTENDED NORTHWARD TO MERRIMACK RIVER MASSACHUSETTS… .INCLUDING BLOCK ISLAND… MARTHA’S VINEYARD… AND NANTUCKET. A TROPICAL STORM WATCH REMAINS IN EFFECT FROM NORTH OF SANDY HOOK NEW JERSEY TO MERRIMACK RIVER MASSACHUSETTS… INCLUDING LONG ISLAND. A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA… GENERALLY WITHIN 36 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA… INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS… PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL WEATHER OFFICE.

AT 500 PM EDT… 2100Z… THE CENTER OF TROPICAL STORM HANNA WAS LOCATED NEAR LATITUDE 30.8 NORTH… LONGITUDE 78.7 WEST OR ABOUT 160 MILES… 255 KM… SOUTH-SOUTHEAST OF CHARLESTON SOUTH CAROLINA AND ABOUT 240 MILES… 385 KM… SOUTH OF WILMINGTON NORTH CAROLINA.

HANNA IS MOVING TOWARD THE NORTH NEAR 20 MPH… 32 KM/HR. THIS MOTION IS EXPECTED CONTINUE TONIGHT… WITH A TURN TOWARD THE NORTHEAST AND A FASTER FORWARD SPEED EXPECTED ON SATURDAY. ON THE FORECAST TRACK… THE CENTER OF HANNA SHOULD CROSS THE SOUTHEASTERN COAST OF THE UNITED STATES TONIGHT OR EARLY SATURDAY… THEN MOVE ALONG THE MID-ATLANTIC COAST LATER SATURDAY AND SATURDAY NIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 70 MPH… 110 KM/HR… WITH HIGHER GUSTS. ALTHOUGH NO SIGNIFICANT CHANGE IN STRENGTH IS FORECAST BEFORE LANDFALL… IT WOULD ONLY TAKE A SMALL INCREASE IN WIND SPEED FOR HANNA TO BECOME A HURRICANE. WEAKENING IS EXPECTED AFTER LANDFALL.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 290 MILES… 465 KM FROM THE CENTER.

THE MINIMUM CENTRAL PRESSURE JUST REPORTED BY AN AIR FORCE RESERVE HURRICANE HUNTER IS 984 MB… 29.06 INCHES.

COASTAL STORM SURGE FLOODING OF 3 TO 5 FEET ABOVE NORMAL TIDE LEVELS… ALONG WITH LARGE AND DANGEROUS BATTERING WAVES… CAN BE EXPECTED NEAR AND TO THE EAST OF THE PATH OF THE CENTER OF HANNA.

HANNA IS EXPECTED TO PRODUCE RAINFALL ACCUMULATIONS OF 3 TO 7 INCHES FROM COASTAL SOUTH CAROLINA… NORTHWARD THROUGH NORTH CAROLINA THROUGH THE MID-ATLANTIC STATES… WHERE ISOLATED MAXIMUM AMOUNTS OF 10 INCHES ARE POSSIBLE. THE POTENTIAL FOR FLASH FLOODING WILL BE SIGNIFICANT FOR THE MID-ATLANTIC REGION AND SOUTHERN NEW ENGLAND. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE POSSIBLE ALONG THE FLORIDA EAST COAST AND COASTAL GEORGIA.

ISOLATED TORNADOES ARE POSSIBLE TONIGHT OVER THE COASTAL AREAS OF SOUTH AND NORTH CAROLINA.

REPEATING THE 500 PM EDT POSITION… 30.8 N… 78.7 W. MOVEMENT TOWARD… NORTH NEAR 20 MPH. MAXIMUM SUSTAINED WINDS… 70 MPH. MINIMUM CENTRAL PRESSURE… 984 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT 800 PM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 1100 PM EDT.

$$ FORECASTER BEVEN

Tropical Discussion:

REPORTS FROM AN AIR FORCE RESERVE HURRICANE HURRICANE HUNTER AIRCRAFT INDICATE THAT HANNA IS JUST BELOW HURRICANE STRENGTH. THE STEPPED FREQUENCY MICROWAVE REPORTED TWO AREAS OF WIND OF ABOUT 65 KT. HOWEVER… DROPSONDE DATA SUGGESTS THAT THE SFMR ESTIMATES WERE A LITTLE TOO HIGH. THE MAXIMUM 850 MB FLIGHT-LEVEL WINDS WERE 75 KT ABOUT 75 N MI EAST OF THE CENTER. THE LAST REPORTED CENTRAL PRESSURE WAS 984 MB… UP A LITTLE FROM THIS MORNING. BASED ON ALL THIS… THE INITIAL INTENSITY IS SET AT 60 KT. IT SHOULD BE NOTED THAT THERE IS NOT MUCH DIFFERENCE METEOROLOGICALLY BETWEEN A 60-KT TROPICAL STORM AND A 65-KT HURRICANE.

THE MOTION IS A SOMEWHAT WOBBLY 360/17… WITH A RE-ANALYSIS OF AIRCRAFT DATA SUGGESTING THIS MOTION BEGAN JUST AFTER THE 11Z AIRCRAFT FIX. HANNA IS MOVING AROUND THE WESTERN END OF THE SUBTROPICAL RIDGE OVER THE WESTERN ATLANTIC AND SHOULD ENTER THE WESTERLIES IN 24-36 HR. THIS SHOULD RESULT IN RECURVATURE TO THE NORTHEAST AND ACCELERATION. ALL GUIDANCE AGREES WITH THIS SCENARIO… AND THERE ARE NO SIGNIFICANT OUTLIERS AMONGST THE DYNAMICAL MODELS. THE NEW FORECAST TRACK IS ADJUSTED A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK AND LIES DOWN THE MIDDLE OF THE GUIDANCE ENVELOPE.

VERTICAL WIND SHEAR AND DRY AIR ENTRAINMENT ARE STILL ISSUES FOR HANNA… AND SIGNIFICANT STRENGTHENING APPEARS UNLIKELY BEFORE LANDFALL. HOWEVER… THERE IS A POSSIBILITY THAT A CONVECTIVE BURST COULD CAUSE THE STORM TO REACH HURRICANE STRENGTH. THE CYCLONE SHOULD WEAKEN AFTER LANDFALL AND BECOME EXTRATROPICAL IN ABOUT 36 HR. THE GFS AND UKMET CONTINUE TO SUGGEST THE POSSIBILITY OF DEEPENING AS AN EXTRATROPICAL SYSTEM LATE IN THE FORECAST PERIOD… AND THIS IS REFLECTED IN THE 96 AND 120 HR FORECASTS.

User Comments
WMBB.com requires that you be a registered site member to post comments and content.
Why Register?
First, we are not being sneaky and gathering your email or other information to sell to telemarketers or e-mail spam companies.

Registration on this site is required simply to allow us to keep people who would post discriminatory, threatening and harassing messages and comments from doing it again.

By having user registration, we hope to provide you with a better user experience. Please view WMBB.com's full Terms & Conditions