| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

---

Tropical Storm ZETA (Text)

ZCZC MIATCDAT5 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM ZETA DISCUSSION NUMBER  28
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
4 AM EST FRI JAN 06 2006
 
SATELLITE IMAGERY THIS MORNING SHOWS THAT ZETA IS BECOMING LESS
ORGANIZED.  THE ASSOCIATED CONVECTION HAS BECOME RAGGED AND LESS
CONCENTRATED OVER THE PAST 6-12 HR...AND THE LOW-LEVEL CIRCULATION
IS LESS WELL-DEFINED THAN IT WAS 24 HR AGO.  FOR NOW...THE INITIAL
INTENSITY REMAINS 35 KT BASED ON A 35 KT SATELLITE INTENSITY
ESTIMATE FROM TAFB AND A 38 KT AMSU INTENSITY ESTIMATE AT 0446 UTC. 
HOWEVER...IT IS POSSIBLE THAT THIS IS A LITTLE GENEROUS.

THE INITIAL MOTION IS 295/6.  ZETA IS ON THE SOUTHWEST SIDE OF A
LOW/MID LEVEL RIDGE OVER THE CENTRAL AND EASTERN ATLANTIC...WHILE A
LARGE DEEP-LAYER TROUGH INTENSIFIES OVER THE WESTERN ATLANTIC. 
ZETA SHOULD CONTINUE GENERALLY WEST-NORTHWESTWARD FOR 24-36 HR AS
THE RIDGE BUILDS WESTWARD A LITTLE...THEN THE CYCLONE SHOULD TURN
NORTHWARD AS IT APPROACHES THE WESTERN ATLANTIC TROUGH.  ALL
DYNAMICAL GUIDANCE AGREES WITH THIS SCENARIO...AND THE NEW FORECAST
TRACK IS MORE OR LESS DOWN THE MIDDLE OF THOSE MODELS.  THE TRACK IS
A LITTLE TO THE LEFT OF THE PREVIOUS TRACK BASED ON THE CURRENT
POSITION AND MOTION.
 
WATER VAPOR IMAGERY SHOWS THAT...AS FORECAST BY THE LARGE-SCALE
MODELS FOR THE PAST TWO DAYS...AN UPPER-LEVEL TROUGH IS PASSING
OVER ZETA WITH A LARGE RIDGE DEVELOPING WEST OF THE TROUGH.  THE
BUILDING RIDGE SHOULD BRING STRONG...AND POSSIBLY SUBSIDENT...
NORTHERLY UPPER-LEVEL FLOW OVER ZETA STARTING IN THE NEXT 6-12 HR. 
THIS SHOULD CAUSE THE CYCLONE TO WEAKEN TO A DEPRESSION LATER
TODAY...AND BECOME A NON-CONVECTIVE REMNANT LOW IN 24-36 HR.  THE
LARGE-SCALE MODELS ALL COMPLETELY DISSIPATE THE SYSTEM IN 48-60 HR. 
GIVEN THAT ZETA HAS BEEN QUITE TENACIOUS...THE INTENSITY FORECAST
WILL CALL FOR THE REMNANTS TO LAST A LITTLE LONGER THAN THAT...WITH
DISSIPATION IN 72-96 HR.
 
FORECASTER BEVEN
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      06/0900Z 23.3N  49.3W    35 KT
 12HR VT     06/1800Z 23.8N  50.5W    30 KT
 24HR VT     07/0600Z 24.6N  52.8W    25 KT...DISSIPATING
 36HR VT     07/1800Z 26.0N  55.5W    25 KT...REMNANT LOW
 48HR VT     08/0600Z 28.5N  57.0W    20 KT...REMNANT LOW
 72HR VT     09/0600Z 32.5N  57.0W    20 KT...REMNANT LOW
 96HR VT     10/0600Z...DISSIPATED
 
 
$$
NNNN