EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
258 PM EDT MON AUG 02 2010
VALID 12Z THU AUG 05 2010 - 12Z MON AUG 09 2010
A SIGNIFICANT WRINKLE IN THE FORECAST IS TROPICAL DEPRESSION FOUR
IN THE CENTRAL TROPICAL ATLANTIC. THE DETERMINISTIC GUIDANCE
MOVES THIS SYSTEM NEAR OR OFFSHORE THE EAST COAST OF NORTH AMERICA
OVER THE NEXT WEEK. THE 12Z GFS/12Z CANADIAN ARE THE FARTHEST
WEST BRINGING IT TOWARDS FLORIDA IN 6-7 DAYS...WHILE THE 12Z
ECMWF/12Z UKMET ARE WELL TO THE RIGHT TRYING TO RECURVE THE SYSTEM
JUST EAST OF THE 70TH MERIDIAN. THE ENSEMBLE GUIDANCE WITH THIS
FEATURE HAS ALSO BEEN QUESTIONABLE WITHIN ANY OF ITS 00Z AND 12Z
RUNS OVER THE PAST SEVERAL DAYS...THOUGH ITS MULTI-DAY WAVERING
FAVORS THE WESTERN ROUTE MOVING THE LOW JUST NORTH OF THE GREATER
ANTILLES UP THE EAST SIDE OF THE BAHAMA BANK AND OFFSHORE THE
FLORIDA COAST. NHC TOOK THE EASTERN ROUTE AT 15Z WHICH WAS A
SIGNIFICANT BREAK FROM YESTERDAYS 16Z NHC/HPC AGREED UPON POINTS.
SEE NHCS LATEST DISCUSSIONS CONCERNING THEIR FORECAST REASONING.
BEYOND FRIDAY MORNING...
THE WEAKENING TROUGH IN THE EAST IS NOT
EXPECTED TO BE STRONG ENOUGH TO CAUSE FULL RECURVATURE. THE COL
IN THE FLOW PATTERN SHOULD REMAIN TO ITS NORTH...SO THE AGREED
UPON POINTS FOR LATE THIS WEEKEND INTO EARLY NEXT WEEK TAKE THE
SYSTEM NORTHWEST IN THE GENERAL DIRECTION OF THE CAROLINAS SOUTH
OF THE NORTHWARD MIGRATING SUBTROPICAL RIDGE AXIS EXPECTED TO
REACH THE 33RD PARALLEL EARLY NEXT WEEK. SEE THE LATEST FORECASTS
FROM NHC CONCERNING THE FUTURE OF TROPICAL DEPRESSION FOUR.
Source:
http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html
