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 281049
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL 
805 AM EDT TUE JUL 28 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...SPECIAL FEATURES...                                          
A STRENGTHENED PRESSURE GRADIENT IS NOTED ACROSS THE CENTRAL 
CARIBBEAN SEA WITH NEAR GALE TO GALE FORCE WINDS OCCURRING FROM 
11N-14N BETWEEN 72W-77W. THESE CONDITIONS ARE FORECAST TO 
DIMINISH BELOW GALE FORCE WARNING CRITERIA BY 28/1200 UTC. SEE 
LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS 
MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...                                     
TROPICAL WAVE EXTENDS FROM 12N29W TO 19N27W MOVING W AT 15 KT. 
THE WAVE COINCIDES WITH BROAD AND VERY SUBTLE 700 MB TROUGHING 
BETWEEN 26W-32W WITH 850 MB RELATIVE VORTICITY FOCUSED NEAR THE 
SOUTHERN EXTENT OF THE WAVE AXIS. ISOLATED MODERATE CONVECTION 
IS FROM 11N-13N BETWEEN 22W-27W.

TROPICAL WAVE EXTENDS FROM 08N47W TO 17N45W MOVING W AT 15 KT. 
THE WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN 45W-53W. 
NO SIGNIFICANT CONVECTION IS OCCURRING WITH THE WAVE AT THIS 
TIME.

TROPICAL WAVE EXTENDS FROM 08N72W TO 18N69W MOVING W AT 15 KT. 
THE WAVE COINCIDES WITH 700 MB TROUGHING BETWEEN 68W-75W WITH NO 
SIGNIFICANT CONVECTION OCCURRING AT THIS TIME.

TROPICAL WAVE EXTENDS FROM 10N85W TO 19N84W MOVING W AT 15-20 
KT. THE WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN 82W-
89W. ISOLATED MODERATE CONVECTION IS FROM 12N-17N BETWEEN 84W-
87W.

...ITCZ/MONSOON TROUGH...                                      
THE MONSOON TROUGH AXIS EXTENDS FROM THE AFRICAN COAST NEAR 
14N17W TO 12N24W TO 11N31W TO 10N37W TO 11N44W. THE 
INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N48W TO 
05N53W. SCATTERED MODERATE CONVECTION IS FROM 07N-13N BETWEEN 
15W-23W.

...DISCUSSION...

GULF OF MEXICO...                                       
NORTHEAST TO EASTERLY FLOW ALOFT INFLUENCES THE GULF BASIN THIS 
MORNING ON THE SOUTHERN PERIPHERY OF A BROAD UPPER LEVEL 
ANTICYCLONIC CIRCULATION ANCHORED OVER THE LOWER MISSISSIPPI 
RIVER VALLEY REGION. WHILE PROVIDING A GENERALLY STABLE 
ENVIRONMENT ALOFT...A SURFACE WEAKNESS IN THE FORM OF A 1013 MB 
LOW CENTERED IN THE NE GULF NEAR 29N83W AND SURFACE TROUGHING 
EXTENDING SW FROM THE LOW TO 27N86W IS PROVIDING FOCUS FOR 
SCATTERED SHOWERS AND TSTMS. THIS ACTIVITY IS OCCURRING FROM 26N-
29N BETWEEN 83W-87W WITH MID-LEVEL ENERGY NOTED OVER THE EASTERN 
GULF CONTINUING TO PROVIDE MARGINAL LIFTING DYNAMICS FOR THE 
CONVECTION. OTHERWISE...A WEAK SURFACE RIDGE ANCHORED BY A 1017 
MB HIGH CENTERED NEAR 23N84W WILL MAINTAIN GENTLE TO MODERATE 
ANTICYCLONIC WINDS THROUGH LATE WEDNESDAY AS THE HIGH DRIFTS 
GRADUALLY NORTHWESTWARD.

CARIBBEAN SEA...                                            
WATER VAPOR IMAGERY INDICATES MOSTLY DRY CONDITIONS ALOFT OVER 
MUCH OF THE CARIBBEAN BASIN THIS MORNING WHICH IS LIMITING ANY 
WIDESPREAD AREAS OF STRONG AND DEEP CONVECTION. HOWEVER THE 
PRESENCE OF A TROPICAL WAVE ALONG 85W IS GENERATING A FEW 
ISOLATED SHOWERS AND TSTMS FROM 12N-17N BETWEEN 84W-87W AND 
ACROSS PORTIONS OF HONDURAS AND NICARAGUA. OTHERWISE...THE 
PRIMARY MARINE IMPACT IS INCREASED TRADES ACROSS CENTRAL 
PORTIONS REACHING NEAR GALE TO GALE FORCE IN CLOSE PROXIMITY TO 
THE COAST OF COLOMBIA. WHILE THE GALE IS FORECAST THROUGH 
28/1200 UTC...THE AREA OF TRADES IS EXPECTED TO PERSIST IN THE 
STRONG BREEZE TO NEAR GALE RANGE THROUGH THURSDAY.

...HISPANIOLA...                               
CURRENTLY...MOSTLY CLEAR SKIES AND FAIR CONDITIONS PREVAIL 
ACROSS THE ISLAND FOR THE MORNING HOURS. GIVEN DRY AND STABLE 
AIR ALOFT ALONG WITH RELATIVELY CLEAR SKIES NOTED ON SATELLITE 
IMAGERY TO THE EAST...NO SIGNIFICANT DEEP CONVECTION IS EXPECTED 
ACROSS THE ISLAND THROUGH TUESDAY INTO WEDNESDAY.

ATLANTIC OCEAN...                                           
WATER VAPOR IMAGERY INDICATED LONGWAVE TROUGHING OVER THE 
WESTERN NORTH ATLC WITH A FEW EMBEDDED SHORTWAVES NEAR THE BASE 
OF THE TROUGHING SLIGHTLY NORTH OF THE DISCUSSION BORDER...ONE 
NEAR 37N51W AND THE OTHER NEAR 37N66W. BOTH SUPPORT WEAK SURFACE 
LOWS AND FRONTS. THE FIRST LOW IS A 1013 MB LOW CENTERED NEAR 
37N47W WITH A COLD FRONT EXTENDING SW TO 30N52W TO 29N57W THEN 
STATIONARY TO 32N60W. THE FRONT CONTINUES AS A WARM FRONT FROM 
THERE INTO A 1010 MB LOW CENTERED NORTH OF BERMUDA NEAR 35N65W. 
THE ASSOCIATED COLD FRONT EXTENDS W-SW FROM THE 1010 MB LOW TO 
33N72W AND BECOMES STATIONARY TO 31N80W. ISOLATED SHOWERS ARE 
OCCURRING WITHIN 90 NM EAST OF THE FIRST COLD FRONT MENTIONED... 
HOWEVER IS RELATIVELY DRIER THAN THE DEEPER SURFACE LOW TO THE 
WEST. GIVEN THE STRONGER MIDDLE TO UPPER LEVEL DYNAMICS WITH THE 
WESTERN-MOST LOW PRESSURE AREA...SCATTERED SHOWERS AND TSTMS ARE 
OCCURRING GENERALLY N OF 28N BETWEEN 65W-79W. OTHERWISE...THE 
REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A 
SURFACE RIDGE ANCHORED BY A 1020 MB HIGH CENTERED NEAR 27N63W 
WITH AXIS EXTENDING FROM THE HIGH CENTER TO A 1017 MB HIGH 
CENTERED IN THE SE GULF OF MEXICO NEAR 24N84W. FINALLY...THE 
REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE 
OF ANOTHER SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED 
S-SE OF THE AZORES NEAR 35N29W.

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

$$
HUFFMAN


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: Tuesday, 28-Jul-2015 10:49:58 UTC