175 
 WTPZ43 KNHC 012042
 TCDEP3
 TROPICAL STORM OLAF DISCUSSION NUMBER   2
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP182009
 200 PM PDT THU OCT 01 2009
  
 THE CYCLONE HAS BECOME A LITTLE BETTER ORGANIZED SINCE THIS 
 MORNING WITH SEVERAL BANDS OF CONVECTION NOTED IN VISIBLE 
 SATELLITE IMAGERY.  A 1702 UTC ASCAT PASS DETECTED AN AREA OF 
 30-35 KT WINDS TO THE SOUTHEAST OF THE CENTER AND BASED ON THESE
 DATA THE SYSTEM IS UPGRADED TO A TROPICAL STORM...THE FIFTEENTH 
 OF THE 2009 EASTERN PACIFIC SEASON.  OLAF IS CURRENTLY OVER 27-28
 DEGREE CELSIUS SSTS...BUT WATER TEMPERATURES GRADUALLY DECREASE
 ALONG THE FORECAST TRACK.  ALSO...AS OLAF MOVES TOWARDS SLIGHTLY
 HIGHER LATITUDES...IT IS EXPECTED TO ENCOUNTER INCREASING SOUTH-
 SOUTHWESTERLY UPPER-LEVEL WINDS.  GIVEN THESE NEGATIVE
 ENVIRONMENTAL FACTORS...ONLY A LITTLE ADDITIONAL STRENGTHENING IS
 SHOWN IN THE OFFICIAL FORECAST.  THE NEW FORECAST IS IN GOOD
 AGREEMENT WITH THE CONSENSUS OF THE INTENSITY GUIDANCE.  OLAF IS
 EXPECTED TO WEAKEN TO A REMNANT LOW IN ABOUT 48 HOURS.
 
 LATEST VISIBLE AND MICROWAVE SATELLITE IMAGERY SUGGEST THAT THE 
 CENTER IS A LITTLE NORTHEAST OF THE EARLIER ESTIMATES.  THE
 HIGHLY UNCERTAIN INITIAL MOTION ESTIMATE IS 300/5.  THE TRACK
 GUIDANCE AND FORECAST REASONING HAS NOT CHANGED MUCH FROM THIS
 MORNING.  OLAF IS EXPECTED TO TURN NORTHWARD AS A TROUGH ALONG THE
 WEST COAST OF THE UNITED STATES WEAKENS THE RIDGE CURRENTLY TO THE
 NORTH OF THE CYCLONE.  THERE REMAINS A LARGE SPREAD IN THE GUIDANCE
 AS TO WHEN AND WHERE OLAF MAY TURN NORTHEASTWARD.  THE MODELS THAT
 MAINTAIN A STRONGER...MORE VERTICALLY DEEP SYSTEM CONTINUE TO
 ACCELERATE OLAF TOWARDS BAJA CALIFORNIA IN A COUPLE OF DAYS. 
 THE OFFICIAL FORECAST CONTINUES TO LEAN TOWARD THE SOLUTION THAT
 OLAF WILL WEAKEN AND BECOME A SHALLOWER SYSTEM.  THIS WOULD RESULT
 IN LESS INFLUENCE FROM THE WEST COAST TROUGH...AND THEREFORE ONLY A
 SLOW NORTHEASTWARD MOTION IS SHOWN IN THE LATTER PART OF THE
 FORECAST.
 
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      01/2100Z 19.4N 117.8W    35 KT
  12HR VT     02/0600Z 19.9N 118.8W    40 KT
  24HR VT     02/1800Z 20.4N 119.6W    35 KT
  36HR VT     03/0600Z 21.0N 120.0W    30 KT
  48HR VT     03/1800Z 22.0N 120.0W    25 KT...REMNANT LOW
  72HR VT     04/1800Z 23.5N 118.0W    20 KT...REMNANT LOW
  96HR VT     05/1800Z...DISSIPATED
  
 $$
 FORECASTER BROWN