000
WTNT44 KNHC 131444
TCDAT4
TROPICAL DEPRESSION NANA DISCUSSION NUMBER   4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL142008
1100 AM EDT MON OCT 13 2008
 
AS EXPECTED...WESTERLY SHEAR HAS CONTINUED TO TAKE ITS TOLL ON NANA.
THE AREAL EXTENT OF THE CONVECTION HAS DECREASED CONSIDERABLY SINCE
YESTERDAY AND THE CENTER REMAINS EXPOSED.  DVORAK INTENSITY
ESTIMATES SUPPORT DOWNGRADING NANA TO A 30-KT TROPICAL DEPRESSION. 
THE SHEAR IS NOT EXPECTED TO DECREASE DURING THE NEXT COUPLE OF
DAYS AND NANA IS FORECAST TO DEGENERATE INTO A REMNANT LOW WITHIN 
A DAY OR SO. 

THE CYCLONE HAS BEEN MOVING ON A WEST TO WEST-NORTHWESTWARD TRACK
AT ABOUT 6 KT.  NANA OR ITS REMNANTS ARE EXPECTED TO MOVE IN A
WEST-NORTHWEST MOTION TO THE SOUTH OF A LOW- TO MID-LEVEL RIDGE
OVER THE EASTERN ATLANTIC UNTIL DISSIPATION.  THE TRACK FORECAST IS
CLOSE TO THE PREVIOUS ADVISORY AND REMAINS ALONG THE SOUTHERN SIDE
OF THE GUIDANCE ENVELOPE.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      13/1500Z 16.8N  39.8W    30 KT
 12HR VT     14/0000Z 17.1N  40.6W    30 KT
 24HR VT     14/1200Z 17.6N  41.7W    25 KT...REMNANT LOW
 36HR VT     15/0000Z 18.5N  43.0W    25 KT...REMNANT LOW
 48HR VT     15/1200Z...DISSIPATED
 
$$
FORECASTER BROWN