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 Cent
er on Facebook Follow the National Hurricane Center on Twitter
FirstGov.gov is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.
 
 

Tropical Storm ALEX


ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM ALEX DISCUSSION NUMBER  10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL012010
1000 PM CDT SUN JUN 27 2010
 
AN AIR FORCE RESERVE UNIT AIRCRAFT HAS BEEN INVESTIGATING ALEX THIS
EVENING AND MEASURED A MINIMUM PRESSURE OF 991 MB AND PEAK
FLIGHT-LEVEL WINDS OF 42 KT NORTH OF THE CENTER. THE PLANE ALSO
MEASURED PEAK SFMR WINDS OF 41 KT TO THE NORTH OF THE CENTER.
SATELLITE IMAGES INDICATE THAT CENTRAL CONVECTION IS REFORMING...
BANDING FEATURES ARE GRADUALLY INCREASING...AND UPPER-LEVEL OUTFLOW
IS WELL-ESTABLISHED IN ALL QUADRANTS EXCEPT THE NORTHWEST.  BASED
UPON THE AIRCRAFT MEASUREMENTS AND THE INCREASED ORGANIZATION ON
SATELLITE IMAGES...ALEX IS ONCE AGAIN UPGRADED TO A TROPICAL
STORM...AND THE ADVISORY INTENSITY IS SET AT 40 KT.
 
ALTHOUGH THE 12-HR AVERAGE INITIAL MOTION ESTIMATE IS 300/6...
SHORTER-TERM FIXES SUGGEST THAT ALEX MAY BE MOVING EVEN SLOWER.
DURING THE FORECAST PERIOD...GLOBAL MODELS FORECAST AN UNUSUALLY
DEEP LONGWAVE TROUGH TO DEVELOP OVER THE NORTHEASTERN UNITED STATES
WHICH SHOULD RESULT IN A TEMPORARY WEAKENING OF MID-LEVEL RIDGING
ALONG THE NORTHERN GULF COAST. THE GFS/CANADIAN MODELS CONTINUE TO
INDICATE A WEAKER VERSION OF THE MID-LEVEL RIDGE AND HENCE A MORE
NORTHWESTERLY OR NORTH-NORTHWESTERLY MOTION...WHILE THE ECMWF/
UKMET/NOGAPS HAVE CONSISTENTLY PREDICTED A STRONGER RIDGE AND MOVE
ALEX ON A MORE WEST-NORTHWESTERLY COURSE. THE OFFICIAL NEW FORECAST
IS QUITE SIMILAR TO THE PREVIOUS ADVISORY...AND CLOSELY FOLLOWS A
CONSENSUS OF THE DYNAMICAL MODELS THAT EXCLUDES THE GFS...SINCE THE
LATTER MODEL APPEARS TO BE SOMEWHAT OF A NORTHERN OUTLIER AT THIS
TIME.
 
NOW THAT THE CENTER OF ALEX HAS EMERGED OVER THE GULF OF
MEXICO...GLOBAL MODELS PREDICT AN ENVIRONMENT CHARACTERIZED BY
LIGHT VERTICAL WIND SHEAR AS ALEX MOVES OVER WARM WATERS. BOTH OF
THESE INGREDIENTS SHOULD FAVOR STEADY INTENSIFICATION
UNTIL LANDFALL.  PERHAPS THE ONE NEGATIVE FACTOR IS THE LARGE SIZE
OF THE CIRCULATION...AS IT MAY TAKE SOME TIME FOR THE CYCLONE TO
CONSOLIDATE FURTHER. GIVEN THE FAVORABLE LARGE-SCALE CONDITIONS...
IT IS STILL PUZZLING THAT THE GFDL/HWRF DO NOT SHOW ALEX
STRENGTHENING TO MORE THAN A TROPICAL STORM DURING THE NEXT SEVERAL
DAYS.  STATISTICAL GUIDANCE...ON THE OTHER HAND...CONTINUES TO
FORECAST A STRONGER TROPICAL CYCLONE AND THE NHC INTENSITY FORECAST
REMAINS CLOSE TO SHIPS/LGEM MODEL OUTPUT.  IN ANY EVENT...IT SHOULD
BE NOTED THAT THE SKILL OF 2 TO 3-DAY INTENSITY FORECASTS IS VERY
LOW.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      28/0300Z 19.4N  91.3W    40 KT
 12HR VT     28/1200Z 20.1N  92.0W    45 KT
 24HR VT     29/0000Z 21.0N  92.7W    50 KT
 36HR VT     29/1200Z 21.9N  93.5W    55 KT
 48HR VT     30/0000Z 22.6N  94.6W    65 KT
 72HR VT     01/0000Z 23.5N  96.7W    85 KT
 96HR VT     02/0000Z 24.3N  98.8W    50 KT...INLAND
120HR VT     03/0000Z 25.0N 101.0W    20 KT...DISSIPATING INLAND
 
$$
FORECASTER KIMBERLAIN/PASCH
 
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 12:09:02 UTC