Hurricane NORA
ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM NORA DISCUSSION NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
8 AM PDT MON OCT 06 2003
SCATTEROMETER PASSES AT 0200Z AND 0600Z DO NOT SHOW ANY WIND
VECTORS OVER 45 KT...AND EVEN SOME OF THESE MAY BE RAIN-INFLATED.
THE INITIAL INTENSITY IS LOWERED TO 50 KT AND THIS MAY STILL BE A
LITTLE HIGH. DEEP CONVECTION HAS DIMINISHED SUBSTANTIALLY IN
EXTENT AND ORGANIZATION SINCE THE LAST ADVISORY.
THE INITIAL MOTION IS HARD TO GAUGE...BUT THE SCATTEROMETER PASSES
SUGGEST LITTLE MOTION...AND PERHAPS THE BEGINNING OF A TURN TO THE
EAST. THE ADVISORY MOTION WILL BE STATIONARY. THE FUTURE TRACK OF
NORA DEPENDS LARGELY ON HOW DEEP A CIRCULATION IT CAN MAINTAIN.
THERE IS A MID- TO UPPER-LEVEL TROUGH TO THE NORTHWEST OF NORA THAT
IS IMPARTING A SOUTHWESTERLY STEERING CURRENT AT THOSE LEVELS.
HOWEVER...WITH DIMINISHING CONVECTION...NORA COULD BECOME A SHALLOW
SYSTEM AND TURN SHARPLY TO THE EAST AND PASS SOUTH OF OLAF. GIVEN
THE DECAY OVER THE PAST SEVERAL HOURS...AND THE 26C WATERS
UNDERNEATH THE CYCLONE...THE OFFICIAL FORECAST CALLS FOR NORA TO
CONTINUE TO GRADUALLY WEAKEN AND TAKE THE MORE SOUTHERN TRACK. A
SIGNIFICANT ADJUSTMENT SOUTHWARD WAS MADE TO THE PREVIOUS
ADVISORY...WITH THE NEW TRACK IN BEST AGREEMENT WITH THE GFS AND
UKMET GUIDANCE.
ALTHOUGH NORA WOULD BE MOVING OVER WARMER WATERS ON THE FORECAST
TRACK...SOUTHWESTERLY OR SOUTHERLY SHEAR IS EXPECTED TO PERSIST.
AS NORA APPROACHES OLAF FROM THE WEST...THE CIRCULATION OF THE
WEAKER NORA MAY BEGIN TO BE SHEARED OUT BY THE CIRCULATION OF OLAF
AND DISSIPATE BEFORE MAKING LANDFALL.
FORECASTER FRANKLIN
FORECAST POSITIONS AND MAX WINDS
INITIAL 06/1500Z 20.3N 113.8W 50 KT
12HR VT 07/0000Z 20.6N 113.7W 45 KT
24HR VT 07/1200Z 20.8N 113.1W 40 KT
36HR VT 08/0000Z 21.0N 112.3W 35 KT
48HR VT 08/1200Z 21.0N 111.0W 30 KT
72HR VT 09/1200Z 23.0N 108.5W 25 KT
96HR VT 10/1200Z 26.5N 107.5W 20 KT...INLAND
120HR VT 11/1200Z...DISSIPATED
NNNN