|
Show Selection: |
| #64771 (Received by flhurricane at: 10:17 PM 05.Jan.2006) TCDAT5 TROPICAL STORM ZETA DISCUSSION NUMBER 27 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 10 PM EST THU JAN 05 2006 HIGH-RESOLUTION DATA FROM A 2100 UTC QUIKSCAT OVERPASS SHOWED MOSTLY 30-KT SPEEDS OUTSIDE OF THE CONVECTION...WITH A SINGLE 35-KT VECTOR THAT MAY BE IN RAIN. DVORAK INTENSITY ESTIMATES ARE 35 KT...30 KT...AND 25 KT FROM TAFB...SAB...AND AFWA RESPECTIVELY. ZETA STILL HAS A WELL-DEFINED LOW-CLOUD CIRCULATION BUT THE DEEP CONVECTION IS LIMITED AND RAGGED...MAKING FOR A RATHER UNIMPRESSIVE-LOOKING SYSTEM. I WILL MAINTAIN AN INTENSITY OF 35 KT FOR THIS ADVISORY...BUT ONE COULD ALSO MAKE A CASE FOR DOWNGRADING THE SYSTEM TO A DEPRESSION. THE CYCLONE IS LIKELY TO REMAIN IN AN ENVIRONMENT OF VERY STRONG SHEAR AND...ALTHOUGH IT SEEMS AS IF ZETA WILL NEVER DIE...THE FORECAST CONTINUES TO SHOW WEAKENING. A LOW-LEVEL RIDGE TO THE NORTHEAST AND A FRONTAL TROUGH TO THE WEST OF THE TROPICAL CYCLONE SHOULD PRODUCE A NORTHWESTWARD TO WEST-NORTHWESTWARD STEERING CURRENT. INITIAL MOTION IS A SLIGHTLY SLOWER 305/6...BUT DYNAMICAL GUIDANCE SUGGEST SOME INCREASE IN FORWARD SPEED OVER THE NEXT FEW DAYS. THIS OFFICIAL FORECAST IS A LITTLE TO THE LEFT OF THE PREVIOUS ONE BUT TO THE RIGHT OF THE LATEST TRACK MODEL CONSENSUS. THE GFDL ACCELERATES ZETA NORTH-NORTHEASTWARD WITH THE MID- TO UPPER-LEVEL FLOW IN THE LATTER HALF OF THE FORECAST PERIOD...BUT IT SHOWS A STRONGER CYCLONE THAN WE ARE EXPECTING BY THAT TIME. IT IS MORE REASONABLE TO ASSUME THAT ZETA WILL BE A WEAKENED SYSTEM...PROBABLY A REMNANT LOW...THAT WILL BE STEERED BY SHALLOW-LAYER WINDS. FORECASTER PASCH FORECAST POSITIONS AND MAX WINDS INITIAL 06/0300Z 23.2N 48.7W 35 KT 12HR VT 06/1200Z 23.9N 49.6W 30 KT 24HR VT 07/0000Z 24.6N 51.6W 25 KT...DISSIPATING 36HR VT 07/1200Z 25.4N 54.0W 25 KT...REMNANT LOW 48HR VT 08/0000Z 27.0N 56.0W 20 KT...REMNANT LOW 72HR VT 09/0000Z 31.5N 57.5W 20 KT...REMNANT LOW 96HR VT 10/0000Z...DISSIPATED |
