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.
 
 

Atlantic Tropical Weather Discussion



000
AXNT20 KNHC 010604
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 AM EDT SAT AUG 01 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0545 UTC.

...TROPICAL WAVES...                                          

A TROPICAL WAVE IS IN THE E TROPICAL ATLC WITH AXIS JUST E OF 
THE CAPE VERDE ISLANDS NEAR 22W...MOVING W AT 10-15 KT OVER THE 
PAST 18 HOURS. METEOSAT ENHANCED IMAGERY SHOW SAHARAN DRY AIR 
AND DUST IN THE NORTHERN WAVE ENVIRONMENT WHERE NO CONVECTION IS 
OBSERVED. HOWEVER...SOUTH OF THE MONSOON TROUGH...ABUNDANT 
MOISTURE AND A DIFFLUENT WIND ENVIRONMENT ALOFT SUPPORT A 
CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION FROM 11N TO 14N 
BETWEEN 18W AND 25W.

A TROPICAL WAVE IS IN THE W TROPICAL ATLC WITH AXIS NEAR 
52W...MOVING W AT 20 KT. THE TOTAL PRECIPITABLE WATER IMAGERY 
SHOW SHALLOW MOISTURE BEHIND THE WAVE AXIS AND DRY AIR AHEAD OF 
IT. THE WAVE IS DEVOID OF CONVECTION AS SAHARAN DRY AIR AND DUST 
COVER THE ENTIRE WAVE ENVIRONMENT. 

A TROPICAL WAVE IS IN THE W CARIBBEAN WITH AXIS NEAR 80W... 
MOVING W AT 15 KT OVER THE PAST 24 HOURS. THE TOTAL PRECIPITABLE 
WATER IMAGERY SHOWS THE WAVE IS ASSOCIATED WITH A SURGE OF DEEP 
MOISTURE. HOWEVER...STRONG DEEP LAYER WIND SHEAR OVER THE SW 
CARIBBEAN IS LIMITING THE CONVECTION TO ISOLATED SHOWERS AND 
TSTMS AHEAD OF THE WAVE AXIS S OF 17N. 

...ITCZ/MONSOON TROUGH...                                      

THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA INTO THE E 
TROPICAL ATLC NEAR 20N16W TO E OF THE EASTERN MOST TROPICAL WAVE 
NEAR 15N20W TO A 1009 MB LOW NEAR 12N35W SW TO 08N49W. THE ITCZ 
BEGINS NEAR 08N50W AND CONTINUES TO COASTAL GUYANA NEAR 07N57W. 
ASIDE FROM THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE NEAR 
THE CAPE VERDE ISLANDS...SCATTERED MODERATE CONVECTION IS FROM 
07N-14N BETWEEN 32W-39W AND FROM 06N-10N BETWEEN 41W-53W.

...DISCUSSION...

GULF OF MEXICO...                                               

DEEP MOISTURE ASSOCIATED WITH A LOW PRESSURE SYSTEM OVER THE SE 
CONUS EXTENDS ACROSS THE NORTHERN GULF WHERE A 1012 MB LOW IS 
ANALYZED NEAR 29N86W ALONG WITH A STATIONARY FRONT EXTENDING 
FROM 31N86W TO THE LOW TO 28N90W TO 29N95W. A DIFFLUENT WIND 
ENVIRONMENT ALOFT OVER THE NORTH-CENTRAL AND NE BASIN BEING 
GENERATED BY THE SE PERIPHERY OF AN UPPER RIDGE SUPPORT 
SCATTERED MODERATE CONVECTION AND TSTMS N OF 26N E OF 93W. OVER 
THE NW BASIN...A 1015 MB HIGH PREVAILS. A MIDDLE-LEVEL LOW OVER 
THE SAME REGION ALONG WITH THE MOISTURE REFERENCED ABOVE SUPPORT 
SCATTERED MODERATE CONVECTION FROM 25N-27N W OF 95W. 
OTHERWISE...SURFACE RIDGING DOMINATES THE SE GULF WHERE 
SCATTERED SHOWERS AND TSTMS ARE OBSERVED. WINDS ARE VARIABLE AND 
LIGHT OVER THE ENTIRE BASIN...EXCEPT THE NE GULF WHERE WINDS ARE 
FROM THE SW RANGING FROM 15 KT TO 20 KT. FRONT WILL MEANDER OVER 
THE N GULF THROUGH THE WEEKEND. THE SURFACE RIDGE WILL CONTINUE 
TO BUILD BACK ACROSS THE GULF THROUGH MON.  

CARIBBEAN SEA...                                                

AN UPPER-LOW IS OVER THE NW CARIBBEAN...WHICH ALONG WITH SHALLOW 
MOISTURE SUPPORT ISOLATED SHOWERS AND TSTMS N OF 18N BETWEEN 80W 
AND 85W. AN UPPER RIDGE DOMINATES ACROSS THE REMAINDER BASIN. A 
TROPICAL WAVE IS BEING ANALYZED OVER THE SW CARIBBEAN WITH AXIS 
NEAR 80W...WHICH IS ENHANCING ISOLATED SHOWERS AND TSTMS AHEAD 
OF ITS AXIS. SEE TROPICAL WAVES SECTION FOR FURTHER DETAILS. EVEN 
THAT MODERATE MOISTURE IS OBSERVED IN SSMI TPW IMAGERY ACROSS 
THE CENTRAL AND SE CARIBBEAN...STRONG DEEP LAYER WIND SHEAR 
ACROSS THE REGION SUPPORT STABLE CONDITIONS. NE TO E WINDS OF 20 
TO 25 KT ARE FROM 11N TO 14N BETWEEN 69W AND 77W WITH SEAS TO 8 
FT. TRADES OF 15 KT ARE W OF 77W. THE TROPICAL WAVE WILL MOVE 
INLAND CENTRAL AMERICA SAT NIGHT. THE NEXT TROPICAL WAVE WILL 
ENTER THE CARIBBEAN SUN. 

...HISPANIOLA...                                                 

SHALLOW MOISTURE ASSOCIATED WITH THE PASSAGE OF A TROPICAL WAVE IS 
ACROSS THE ISLAND SUPPORTING CLOUDINESS. HOWEVER...NO CONVECTION 
IS OBSERVED AT THIS TIME. MOISTURE IS EXPECTED TO DECREASE SAT 
MORNING AS SAHARAN DRY AIR AND DUST START TO MOVE ACROSS THE 
ISLAND AHEAD OF THE NEXT TROPICAL WAVE TO ENTER THE CARIBBEAN 
SUNDAY NIGHT.

ATLANTIC OCEAN...                                               

A MIDDLE TO UPPER LEVEL LOW IS OVER THE SW N ATLC ALONG WITH 
SHALLOW MOISTURE AHEAD OF A FRONTAL SYSTEM OVER THE SE CONUS. 
LOW LEVEL MOISTURE CONVERGENCE IN THIS REGION AND A DIFFLUENT 
WIND ENVIRONMENT ALOFT BEING GENERATED BY UPPER RIDGING ACROSS 
THE GULF OF MEXICO SUPPORT SCATTERED MODERATE CONVECTION AND 
TSTMS N OF 23N W OF 75W. SURFACE RIDGING DOMINATES ACROSS THE 
REMAINDER BASIN...THUS FAVORING FAIR WEATHER. FOR TROPICAL WAVES 
INFORMATION SEE SECTION ABOVE. 

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

$$
NR


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 USA
nhcwebmaster@noaa.gov
Disclaimer
Credits
Information Quality
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities
Page last modified: Saturday, 01-Aug-2015 06:04:39 UTC