| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

Atlantic Tropical Weather Discussion (Text)



000
AXNT20 KNHC 031725
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 PM EDT MON AUG 03 2015

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL  
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF 
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE 
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE 
IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL 
ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...SPECIAL FEATURES...

GALE FORCE WINDS ARE EXPECTED ALONG THE COAST OF COLOMBIA FROM 
11N-13N BETWEEN 74W-77W UNTIL 1800 UTC THIS AFTERNOON. THESE 
WINDS ARE ASSOCIATED WITH THE TIGHT PRESSURE GRADIENT BETWEEN 
THE W ATLANTIC SURFACE RIDGE AND THE LOWER PRESSURE OVER SOUTH 
AMERICA. PLEASE SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO 
HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.  

...TROPICAL WAVES...                                          

A TROPICAL WAVE IS OVER THE EASTERN ATLANTIC WITH AN AXIS 
EXTENDING FROM 18N35W TO 10N35W...MOVING W AT AROUND 10 KT OVER 
THE PAST 24 HOURS. CURRENT MODEL GUIDANCE SHOWS A 700 MB 
TROUGHING ALONG 35W. DESPITE THE FACT THAT THE WAVE IS EMBEDDED 
IN HIGH MOISTURE MAINLY S OF 13N...NO CONVECTION IS ASSOCIATED 
TO THIS FEATURE DUE TO A BROAD SAHARAN DUST AIRMASS THAT 
PREVAILS ACROSS THE TROPICAL ATLANTIC INHIBITING SIGNIFICANT 
CONVECTION.  

A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS EXTENDING 
FROM 21N45W TO 10N46W...MOVING W AT AT 10 TO 15 KT. THIS WAVE 
COINCIDES WITH A 700 MB TROUGH BETWEEN 35W AND 45W. TPW IMAGERY 
SHOWS A DRY ENVIRONMENT SURROUNDING THIS WAVE AND WITH SAHARAN 
DUST ALSO PREVAILING...NO SIGNIFICANT CONVECTION IS DEVELOPING 
AT THIS TIME ACROSS THIS AREA. 

A TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN WITH AN AXIS 
EXTENDING ACROSS HISPANIOLA FROM 20N71W TO 13N72W...MOVING W AT 
15 TO 20 KT OVER THE PAST 24 HOURS. THIS WAVE COINCIDES WITH 700 
MB TROUGHING BETWEEN 70W AND 80W AND VISIBLE IMAGERY DEPICTS 
FAIRLY CLEAR THE CHARACTERISTIC INVERTED V S OF HISPANIOLA. NO 
CONVECTION IS RELATED TO THIS WAVE AT THIS TIME. 

...ITCZ/MONSOON TROUGH... 

THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E 
TROPICAL ATLANTIC NEAR 18N16W TO 14N31W...THEN RESUMES W OF A 
TROPICAL WAVE NEAR 12N37W TO 12N45W. THE ITCZ BEGINS W OF A 
TROPICAL WAVE NEAR 11N48W TO 11N60W. ISOLATED MODERATE 
CONVECTION PREVAILS S OF THE MONSOON TROUGH AXIS FROM 07N-14N 
AND W OF 23W AND FROM 06N-11N BETWEEN 36W-46W. 

...DISCUSSION...

GULF OF MEXICO...  

AN UPPER-LEVEL RIDGE IS CENTERED OVER NW MEXICO AND EXTENDS E 
ACROSS THE BASIN. WITH THIS...UPPER-LEVEL DIFFLUENCE PREVAILS 
ALONG THE GULF STATES COAST SUPPORTING CONVECTION N OF 28N. AT 
THE SURFACE...A 1009 MB LOW IS CENTERED OVER NORTHERN FLORIDA 
30N83W. A SURFACE TROUGH EXTENDS FROM THE LOW CENTER TO NEAR 
26N87W. THE COMBINATION OF DEEP MOISTURE...LOW-LEVEL 
CONVERGENCE...AND THE UPPER DIFFLUENCE PREVIOUSLY MENTIONED 
SUPPORTS NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE EASTERN 
HALF OF THE BASIN MAINLY E OF 87W. THE REMAINDER OF THE BASIN 
CONTINUES CONVECTION FREE WITH THE SURFACE RIDGE THAT PREVAILS 
ACROSS THE ATLANTIC EXTENDING W REACHING THE GULF WATERS. A 
GENTLE TO MODERATE ANTICYCLONIC FLOW IS OBSERVED IN 
SCATTEROMETER DATA ACROSS THE GULF. OVER THE NEXT 24 
HOURS...EXPECT FOR CONVECTION TO CONTINUE ACROSS THE NORTH AND 
EAST GULF AS THE SURFACE LOW CONTINUES IN THE VICINITY. 

CARIBBEAN SEA... 

AN UPPER-LEVEL LOW IS CENTERED OVER E CUBA NEAR 21N76W WITH 
CYCLONIC FLOW ALOFT COVERING THE WHOLE BASIN. TPW IMAGERY 
DEPICTS A MOIST ENVIRONMENT PREVAILING OVER THE WESTERN 
CARIBBEAN THAT COMBINED WITH THIS UPPER LOW...ARE ENHANCING 
CLOUDINESS AND ISOLATED CONVECTION ACROSS PORTIONS OF CUBA AND 
THE W CARIBBEAN MAINLY N OF 18N AND W OF 75W. TO THE E...A 
TROPICAL WAVE IS MOVING OVER HISPANIOLA AHEAD OF A SAHARAN 
AIRMASS THAT CONTINUES INHIBITING CONVECTION ACROSS THE E 
CARIBBEAN MAINLY E OF 72W. SCATTEROMETER DATA DEPICTS GENTLE TO 
MODERATE TRADES ACROSS THE BASIN WITH HIGHER SPEEDS S OF 14N 
BETWEEN 74W-77W. PLEASE REFER TO THE SPECIAL FEATURES SECTION 
FOR MORE DETAILS. OVER THE NEXT 24 HOURS...CONVECTION WILL 
REMAIN POSSIBLE OVER THE NW CARIBBEAN AS THE TROPICAL WAVE 
CONTINUES MOVING W.

...HISPANIOLA... 

A TROPICAL WAVE IS MOVING ACROSS THE ISLAND WITH AXIS CURRENTLY 
ALONG 71W. ISOLATED MODERATE CONVECTION IS EXPECTED AS THE WAVE 
CONTINUES MOVING W. A SAHARAN AIRMASS PREVAILS BEHIND THIS WAVE 
THEREFORE...DRY WEATHER CONDITIONS ARE EXPECTED AFTER THE WAVE 
MOVES THROUGH.

ATLANTIC OCEAN... 

A 1009 MB SURFACE LOW IS MOVING NE ACROSS NORTHERN FLORIDA. A 
STATIONARY FRONT EXTENDS FROM THE LOW ACROSS THE NW ATLANTIC 
SUPPORTING CONVECTION N OF 32N. TO THE E...A SURFACE TROUGH 
EXTENDS FROM 24N71W TO 29N66W. SCATTERED MODERATE CONVECTION IS 
OBSERVED FROM 22N-30N BETWEEN 67W-72W. A SURFACE RIDGE PREVAILS 
ACROSS THE REMAINDER OF THE BASIN ANCHORED BY A 1025 MB SURFACE 
HIGH NEAR 33N55W AND A 1020 MB HIGH CENTERED NEAR 31N18W. A 
BROAD AREA OF SAHARAN DUST CONTINUES TO INHIBIT ANY SIGNIFICANT 
CONVECTION ACROSS THE BASIN. OVER THE NEXT 24 HOURS...EXPECT FOR 
CONVECTION TO CONTINUE FROM THE BAHAMAS TO THE N FL COAST AS THE 
SURFACE LOW CONTINUES IN THE VICINITY. ISOLATED CONVECTION IS 
ALSO EXPECTED ALONG THE SURFACE TROUGH AS IT MOVES NW OVER THE W 
ATLANTIC. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
WWW.HURRICANES.GOV/MARINE

$$ 

ERA

Standard version of this page

Alternate Formats
About Alternates - E-Mail Advisories - RSS Feeds

Cyclone Forecasts
Latest Advisory - Past Advisories - About Advisories

Marine Forecasts
Latest Products - About Marine Products

Tools & Data
Satellite Imagery - US Weather Radar - Aircraft Recon - Local Data Archive - Forecast Verification - Deadliest/Costliest/Most Intense

Learn About Hurricanes
Storm Names Wind Scale - Prepare - Climatology - NHC Glossary - NHC Acronyms - Frequently Asked Questions - AOML Hurricane-Research Division

About Us
About NHC - Mission/Vision - Other NCEP Centers - NHC Staff - Visitor Information - NHC Library

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
Privacy Policy
Credits
About Us
Glossary
Career Opportunities
Page last modified: Monday, 03-Aug-2015 17:25:29 UTC