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

Atlantic Tropical Weather Discussion (Text)



000
AXNT20 KNHC 311756
TWDAT 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 PM EDT MON AUG 31 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...                                         
HURRICANE FRED IS CENTERED NEAR 16.9N 24.2W AT 31/1800 UTC OR 
ABOUT 20 NM NNE OF RIBEIRA BRAVA IN THE CAPE VERDE ISLANDS AND 
ABOUT 50 NM ESE OF RIBEIRA GRANDE IN THE CAPE VERDE ISLANDS 
MOVING NW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 986 
MB. MAXIMUM SUSTAINED WIND SPEED IS 75 KT WITH GUSTS TO 90 KT. 
SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 14N-
18N BETWEEN 22W-25W. SCATTERED MODERATE IS ELSEWHERE FROM 17N-
21N BETWEEN 15W-20W...AND FROM 09N-14N BETWEEN 22W-28W. SEE 
LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCPAT1/WTNT31 KNHC AND THE FULL FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS.

...TROPICAL WAVES...                                            
TROPICAL WAVE EXTENDS FROM 10N60W TO 19N57W MOVING W AT 15-20 
KT. THE WAVE COINCIDES WITH RELATIVELY BROAD 700 MB TROUGHING 
BETWEEN 55W-63W...WITH A MAXIMUM IN 850 MB RELATIVE VORTICITY 
ALONG THE WAVE AXIS FROM 12N-17N. ISOLATED MODERATE CONVECTION 
IS FROM 18N-21N BETWEEN 54W-59W.

TROPICAL WAVE EXTENDS FROM 10N75W TO 19N75W MOVING W AT 25 KT. 
THE WAVE LIES WITHIN THE SOUTHWESTERN PERIPHERY OF THE LOW TO 
MID-LEVEL SUBTROPICAL RIDGE ANCHORED OVER THE SW NORTH ATLC NEAR 
30N69W. ISOLATED MODERATE CONVECTION IS FROM 16N-19N BETWEEN 75W-
78W. 

...ITCZ/MONSOON TROUGH...                                     
THE MONSOON TROUGH AXIS EXTENDS FROM 12N28W TO A 1013 MB LOW 
NEAR 07N38W TO 08N45W. OUTSIDE OF CONVECTION ASSOCIATED WITH 
HURRICANE FRED...ISOLATED MODERATE CONVECTION IS FROM 05N-08N 
BETWEEN 40W-43W.

...DISCUSSION...

GULF OF MEXICO...                                                
A MIDDLE TO UPPER LEVEL TROUGH AXIS EXTENDS FROM OVER THE OHIO 
RIVER VALLEY SW TO OVER THE ARKLATEX REGION TO A BROAD BASE OVER 
THE RIO GRANDE RIVER VALLEY NEAR 26N100W. THE TROUGHING IS 
PROVIDING MUCH OF THE GULF WITH SOUTHWESTERLY FLOW ALOFT THIS 
AFTERNOON. NEAREST TO THE MID-LEVEL 500 MB RELATIVE VORTICITY 
MAXIMUM OVER SOUTHERN TEXAS AND NE MEXICO...MIDDLE TO UPPER 
LEVEL DIFFLUENCE IS GENERATING SCATTERED SHOWERS AND TSTMS 
ACROSS THE WESTERN GULF N OF 22N W OF 93W. FARTHER EAST...A 
MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR 
IMAGERY MOVING OVER THE EAST-CENTRAL GULF WATERS NEAR 27N83W. 
THE SHORTWAVE SUPPORTS A WEAK 1014 MB LOW CENTERED NEAR 25N85W 
WITH SURFACE TROUGHING EXTENDING N-NE TO THE FLORIDA BIG BEND 
REGION NEAR 30N83W...AND SW FROM THE LOW TO NEAR THE NW CORNER 
OF THE YUCATAN PENINSULA NEAR 21N90W. GIVEN THE FAVORABLE UPPER 
LEVEL ENVIRONMENT ALOFT AND MAXIMUM LOW-LEVEL MOISTURE 
CONVERGENCE ALONG AND EAST OF THE SURFACE TROUGHING...SCATTERED 
SHOWERS AND ISOLATED TSTMS ARE OCCURRING FROM 24N-27N BETWEEN 
82W-84W...AND S OF 23N BETWEEN 83W-87W...INCLUDING THE 
APPROACHES TO THE YUCATAN CHANNEL. OTHERWISE...GENERALLY GENTLE 
TO MODERATE ANTICYCLONIC FLOW PERSISTS AS SURFACE HIGH PRESSURE 
REMAINS ANCHORED ACROSS A LARGE PORTION OF THE MID-ATLC AND SE 
CONUS THROUGH THURSDAY.

CARIBBEAN SEA...                                            
UPPER LEVEL RIDGING EXTENDS OVER THE YUCATAN CHANNEL REGION AND 
MUCH OF THE NW CARIBBEAN THIS AFTERNOON. GIVEN THE FAVORABLE 
UPPER LEVEL DIFFLUENT ENVIRONMENT...SCATTERED SHOWERS AND TSTMS 
ARE OCCURRING N OF 19N BETWEEN 82W-88W...INCLUDING FAR WESTERN 
CUBA...AND THE FAR EASTERN YUCATAN PENINSULA. OTHERWISE...THE 
OTHER MAIN UPPER LEVEL FEATURE IMPACTING THE BASIN IS A BROAD 
UPPER LEVEL LOW CENTERED OVER THE WINDWARD PASSAGE REGION NEAR 
18N75W. THE UPPER LEVEL LOW ALONG WITH A WEAK TROPICAL WAVE 
ALONG 76W IS GENERATING A FEW ISOLATED SHOWERS AND TSTMS IN THE 
VICINITY OF JAMAICA AND ACROSS AN AREA SOUTH OF HISPANIOLA IN 
THE VICINITY OF 16N72W. FINALLY...THE APPROACH OF ANOTHER 
TROPICAL WAVE...CURRENTLY ALONG 59W...IS EXPECTED TO INCREASE 
PRECIPITATION PROBABILITIES FOR THE LESSER ANTILLES THIS 
AFTERNOON THROUGH EARLY TUESDAY. ISOLATED SHOWERS AND POSSIBLE 
ISOLATED TSTMS ALONG WITH POSSIBLE GUSTY WINDS WILL ACCOMPANY 
THE WAVE AS IT ENTERS THE EASTERN CARIBBEAN BY TUESDAY AFTERNOON.

...HISPANIOLA...                                                 
CURRENTLY...MOSTLY CLEAR SKIES ARE NOTED ON VISIBLE SATELLITE 
IMAGERY DUE LARGELY TO RELATIVELY DRY CONDITIONS ALOFT AND 
OVERALL STABILITY PROVIDED BY THE SUBTROPICAL RIDGE ANCHORED 
ACROSS THE SW NORTH ATLC REGION. LITTLE CHANGE IN SYNOPTIC 
CONDITIONS ARE EXPECTED THROUGH TUESDAY AFTERNOON WHEN A 
TROPICAL WAVE CURRENTLY ALONG 59W WILL APPROACH AND INCREASE 
PROBABILITY OF PRECIPITATION ACROSS THE ISLAND.

ATLANTIC OCEAN...                                              
AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS ANCHORED OVER THE SW 
NORTH ATLC NEAR 29N71W WITH A RIDGE AXIS EXTENDING W TO 29N77W 
THEN SW OVER THE SOUTHERN FLORIDA PENINSULA. LOW-LEVEL MOISTURE 
CONVERGENCE ALONG WITH MIDDLE TO UPPER LEVEL DIFFLUENCE ON THE 
PERIPHERY OF THE RIDGING IS GENERATING SCATTERED SHOWERS AND 
TSTMS N OF 30N BETWEEN 78W-80W. OTHERWISE...THE MAIN FEATURE 
INFLUENCING THE SW NORTH ATLC IS A SURFACE RIDGE ANCHORED BY A 
1022 MB HIGH CENTERED NEAR 31N69W. FARTHER EAST...THE CENTRAL 
ATLC IS GENERALLY UNDER THE INFLUENCE OF A WEAKER SURFACE RIDGE 
ANCHORED BY A 1020 MB HIGH CENTERED NEAR 23N45W...HOWEVER TO THE 
NW A WEAK 1018 MB LOW IS CENTERED NEAR 33N56W WITH A SURFACE 
TROUGH EXTENDING SW TO 29N61W. SCATTERED SHOWERS AND TSTMS ARE 
OCCURRING FROM 30N-33N BETWEEN 52W-56W. FINALLY...AS MENTIONED 
ABOVE...THE MAIN FOCUS FOR THE EASTERN ATLC IS HURRICANE FRED AS 
IT TRACKS ACROSS THE CAPE VERDE ISLANDS THIS AFTERNOON.

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

$$
HUFFMAN

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, 31-Aug-2015 17:56:28 UTC