Skip Navigation Links weather.gov   
NOAA logo - Click to go to the NOAA homepage National Weather Service   NWS logo - Click to go to the NWS homepage
National Hurricane Center
Local forecast by
"City, St" or "ZIP"

 
Alternate Formats
   Text     |   Mobile
   Email   |   RSS XML/RSS logo
   About Alternates
Cyclone Forecasts
   Latest Advisory
   Past Advisories
   Audio/Podcasts
   About Advisories
Marine Forecasts
   Atlantic & E Pacific
   Gridded Marine
   About Marine
Tools & Data
   Satellite | Radar
   Analysis Tools
   Aircraft Recon
   GIS Datasets
   Data Archive
Development
   Experimental
   Research
   Forecast Accuracy
Outreach & Education
   Prepare
   Storm Surge
   About Cyclones
   Cyclone Names
   Wind Scale
   Most Extreme
   Forecast Models
   Breakpoints
   Resources
   Glossary | Acronyms
   Frequent Questions
Our Organization
   About NHC
   Mission & Vision
   Staff | Q&A
   Visitors | Virtual Tour
   Library Branch
   NCEP | Newsletter
Contact Us
   Comments
Follow the National Hurricane Center on Facebook Follow the National Hurricane Center on Twitter
Subscribe the National Hurricane Center on YouTube Read the National Hurricane Center Inside the Eye blog on WordPress
FirstGov.gov is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.
 
 

Tropical Storm COLIN


ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM COLIN DISCUSSION NUMBER  13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL042010
1100 PM AST FRI AUG 06 2010
 

COLIN IS A SHEARED CYCLONE WITH INCREASING CONVECTION NEAR AND TO
THE EAST OF THE CENTER AT THIS TIME. THIS COULD GIVE AN IMPRESSION
OF A STRONGER CYCLONE BUT FLUCTUATIONS IN CONVECTION ARE TYPICAL IN
SHEARED SYSTEMS.  THE STRONG UPPER-LEVEL WINDS CURRENTLY OVER THE
CYCLONE WILL PROBABLY SEPARATE THE CENTER FROM THE THUNDERSTORM
ACTIVITY AGAIN SOON. THEREFORE...THE INITIAL INTENSITY IS KEPT AT
40 KNOTS. ANOTHER RECONNAISSANCE PLANE WILL CHECK COLIN IN SEVERAL
HOURS. COLIN HAS A SMALL WINDOW OF OPPORTUNITY TO GATHER SOME
STRENGTH WITHIN THE NEXT DAY OR SO...IF THE SHEAR RELAXES A BIT AS
DIAGNOSED BY THE SHIPS MODEL. IN FACT...IF THE CURRENT INCREASE IN
CONVECTION CONTINUES OR PERSIST IT COULD MEAN THAT THE SHEAR IS
ALREADY RELAXING AND SLIGHT INTENSIFICATION IS ABOUT TO BEGIN. THE
OFFICIAL FORECAST ASSUMES THAT THE SHEAR WILL RELAX A BIT AND CALLS
FOR A SMALL INCREASE IN INTENSITY. BY 96 HOURS...COLIN SHOULD BE
EXTRATROPICAL AND THEN BECOME ABSORBED BY A LARGER CYCLONE. THE
INTENSIFICATION SHOWN IN BOTH THE GFDL AND HWRF MODELS OCCURS LATE
IN THE FORECAST PERIOD. THIS DOES NOT SEEM TO BE REALISTIC BECAUSE
BY THEN...THE CYCLONE IS EXPECTED TO BE REACHING COOLER WATERS AND
BECOMING EXTRATROPICAL.  

THE CENTER IS CLEARLY OBSERVED ON THE WESTERN EDGE OF THE CONVECTION
AND ONE CAN OBTAIN A GOOD ESTIMATE OF THE INITIAL MOTION...WHICH IS
TOWARD THE NORTH OR 010 DEGREES AT 8 KNOTS. COLIN IS ALREADY ON THE
WESTERN EDGE OF THE SUBTROPICAL RIDGE AND IS NEARING THE
MID-LATITUDE WESTERLIES. THEREFORE...THE CYCLONE SHOULD GRADUALLY
TURN MORE TO THE NORTH-NORTHEAST WITH SOME INCREASE IN FORWARD
SPEED. THERE IS GOOD CONFIDENCE IN THE FORECAST BECAUSE THE TRACK
GUIDANCE IS PACKED AND THE OFFICIAL FORECAST IS IN THE MIDDLE OF
THE ENVELOPE. THE ONLY DIFFERENCE IS IN THE FORWARD SPEED SHOWN BY
VARIOUS MODELS...BUT THIS MOSTLY OCCUR AT THE LONG RANGE AS THE
SYSTEM BEGINS THE TRANSITION TO AN EXTRATROPICAL LOW.       

 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      07/0300Z 29.1N  66.5W    40 KT
 12HR VT     07/1200Z 30.3N  66.1W    40 KT
 24HR VT     08/0000Z 32.0N  65.2W    45 KT
 36HR VT     08/1200Z 33.7N  64.4W    55 KT
 48HR VT     09/0000Z 36.5N  63.0W    55 KT
 72HR VT     10/0000Z 42.0N  57.5W    55 KT
 96HR VT     11/0000Z 49.5N  46.5W    45 KT...POST-TROP/EXTRATROP
120HR VT     12/0000Z...ABSORBED BY A LARGER EXTRATROPICAL CYCLONE 
 
$$
FORECASTER AVILA
 
NNNN


Quick Navigation Links:
Tropical Cyclone Forecasts  -  Tropical Marine Forecasts  -  Data Archive
Outreach  -  Prepare  -  About Cyclones  -  About NHC  -  Contact Us

NOAA/ National Weather Service
National Centers for Environmental Prediction
National Hurricane Center
11691 SW 17th Street
Miami, Florida 33165-2149 USA
nhcwebmaster@noaa.gov
Disclaimer
Credits
Information Quality
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities
Page last modified: Friday, 15-Apr-2011 12:09:04 UTC