Image Department Meteorology
Meteorology_Home Weather_Server News/Seminars
People
Research
Academics Application Contact_Us

Hawaiian_Weather
US_Mainland_Weather
Tropical_Weather
Satellite_Imagery
Radar_Imagery
Marine
Numerical_Models
LAPS
Forecasts
Observations
Archive
Links Disclaimer
Space
SOEST_Home
University_of_Hawaii_Home

 636 
 WTPZ41 KNHC 011455
 TCDEP1
 HURRICANE JOHN DISCUSSION NUMBER  17
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP112006
 800 AM PDT FRI SEP 01 2006
  
 A DROPSONDE FROM AN AIR FORCE RESERVE HURRICANE HUNTER JUST REPORTED
 A CENTRAL PRESSURE OF 956 MB WITH 19 KT OF SURFACE WINDS...WHICH
 INDICATES A CENTRAL PRESSURE OF ABOUT 954 MB. HOWEVER THE PEAK
 FLIGHT LEVEL WINDS SO FAR ARE 98 KT. THE PLANE HASN'T SAMPLED THE
 ENTIRE STORM... AND WITH SUCH A LOW CENTRAL PRESSURE... THE INITIAL
 INTENSITY WILL BE HELD AT 100 KT.  SATELLITE IMAGES INDICATE THAT
 THE RING OF THUNDERSTORMS AROUND THE CENTER OF JOHN HAS WARMED SOME
 THIS MORNING... THOUGH THE EYE IS BECOMING WARMER AND
 BETTER-DEFINED. THESE CHANGES MAY BE DUE TO ONGOING AN EYEWALL
 REPLACEMENT CYCLE... AS SEEN ON CABO SAN LUCAS RADAR... WHICH MAKES
 INTENSITY ESTIMATES RATHER UNCERTAIN.  
  
 JOHN HAS SLOWED CONSIDERABLY... AND IS NOW ESTIMATED TO BE MOVING
 310/6. THIS SLOW-DOWN SHOULD BE TEMPORARY WITH HIGH PRESSURE LOCKED
 IN PLACE OVER NORTHEAST MEXICO... WHICH SHOULD PUSH JOHN ALONG
 SOON. ALL GUIDANCE SHOWS SOME ACCELERATION AND IS TIGHTLY CLUSTERED
 NEAR THE SOUTHERN TIP OF BAJA CALIFORNIA IN ABOUT 12 HOURS. THIS
 NORTHWESTWARD MOTION SHOULD CONTINUE THROUGH ABOUT 36 HOURS.
 THEREAFTER MODELS ARE DIVERGENT... WITH THE GFS/GFDL FARTHER TO THE
 RIGHT SHOWING A THREAT TO NORTHERN BAJA CALIFORNIA... WHILE THE
 OTHER MODELS INDICATE A TURN TO THE WEST-NORTHWEST AWAY FROM LAND.
 THE OFFICIAL FORECAST IS SHIFTED A LITTLE TO NORTH IN THE SHORT-
 TERM TO ACCOUNT FOR THE INITIAL MOTION... AND LATER IN THE PERIOD
 IS ADJUSTED SLIGHTLY TO THE NORTH OF THE PREVIOUS TRACK CLOSER TO
 THE CONSENSUS OF THE GLOBAL MODELS.
  
 THERE COULD STILL BE A LITTLE STRENGTHENING BEFORE JOHN NEARS THE
 COAST TONIGHT. SHIPS INTENSITY GUIDANCE SHOWS LITTLE SHEAR AND THE
 WATERS ARE QUITE WARM IN THAT AREA. THEREAFTER...INTERACTION WITH
 LAND AND COOLER WATERS WEST OF THE BAJA PENINSULA SHOULD FORCE A
 GRADUAL WEAKENING. JOHN WILL LIKELY WEAKEN AT A FAST RATE BEYOND 48
 HOURS AS IT ENCOUNTERS SSTS OF 23-24 DEGREES CELSIUS.... LIKELY
 CAUSING DISSIPATION NEAR THE END OF THE PERIOD.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      01/1500Z 22.0N 108.8W   100 KT
  12HR VT     02/0000Z 22.9N 110.0W   105 KT...INLAND NEAR COAST
  24HR VT     02/1200Z 24.0N 111.5W   100 KT
  36HR VT     03/0000Z 24.8N 112.8W    95 KT
  48HR VT     03/1200Z 25.5N 114.2W    80 KT
  72HR VT     04/1200Z 26.3N 116.6W    60 KT
  96HR VT     05/1200Z 26.5N 119.5W    35 KT
 120HR VT     06/1200Z 26.5N 123.0W    25 KT...DISSIPATING
  
 $$
 FORECASTER BLAKE/AVILA
  
 
Return to the Tropical Systems Page for JOHN

Back to main Tropical Weather page




This page is maintained voluntarily by the MKWC and the UHMET faculty, staff, and students.
It was last modified on: Thu, Jul 23 2020 - 2003 UTC
Send comments to: Ryan Lyman