[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 122338
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED AUG 12 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2330 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS AT ABOUT 170 NM E OF THE CAPE VERDE ISLANDS
WITH AXIS EXTENDING FROM 16N27W TO 10N27W...MOVING W AT 10 KT.
THE WAVE COINCIDES WITH 700 MB TROUGHING BETWEEN 22W-30W. NO
SIGNIFICANT CONVECTION IS OCCURRING WITH THE WAVE AT THIS TIME.

A TROPICAL WAVE IS MOVING ACROSS THE CENTRAL TROPICAL ATLANTIC
WITH AXIS EXTENDING FROM 15N47W TO 07N50W...MOVING W AT 10-15
KT. THE WAVE COINCIDES WITH A SUBTLE 700 MB TROUGHING BETWEEN
45W-55W. VISIBLE SATELLITE IMAGERY DEPICTS CLOUDINESS IN THE
ENVIRONMENT OF THIS WAVE AND SOME MID-LEVEL TURNING MAINLY ALONG
50W. ISOLATED MODERATE CONVECTION IS FROM 10N-14N BETWEEN 46W-
53W.

A TROPICAL WAVE IS IN THE CENTRAL CARIBBEAN WITH AXIS EXTENDING
FROM 19N76W TO 08N77W...MOVING W AT 15-20 KT. THE WAVE COINCIDES
WITH BROAD 700 MB TROUGHING BETWEEN 66W-86W. ISOLATED CONVECTION
IS CURRENTLY OBSERVED IN THE ENVIRONMENT OF THIS WAVE AND ACROSS
THE CARIBBEAN SUPPORTED BY AN UPPER-LEVEL LOW CENTERED NEAR
19N78W.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM A 1010 MB LOW CENTERED OVER THE
AFRICAN COAST NEAR 15N16W TO 09N37. THE INTERTROPICAL
CONVERGENCE ZONE AXIS EXTENDS FROM THIS POINT TO 10N48W...THEN
RESUMES W OF A TROPICAL WAVE NEAR 08N52W TO 06N55W. ASIDE FROM
THE CONVECTION RELATED TO THE TROPICAL WAVE ALONG 50W...ISOLATED
CONVECTION IS FROM 06N-09N BETWEEN 29W-41W.

...DISCUSSION...

GULF OF MEXICO...

AN UPPER-LEVEL RIDGE IS CENTERED OVER NORTHERN TEXAS AND EXTENDS
ACROSS THE BASIN. AT THE SURFACE...A 1018 HIGH IS LOCATED NEAR
24N90W SUPPORTING A LIGHT TO GENTLE ANTICYCLONIC FLOW ACROSS THE
AREA. SCATTERED MODERATE CONVECTION PREVAILS ACROSS THE YUCATAN
PENINSULA AFFECTING PORTIONS OF THE BAY OF CAMPECHE MAINLY S OF
21N AND E OF 95W. TO THE N...A PRE-FRONTAL TROUGH EXTENDS ACROSS
THE NORTHERN GULF AND NORTHERN FLORIDA FROM 27N94W TO 30N85W
THEN INTO THE W ATLANTIC NEAR 31N81W. ISOLATED CONVECTION IS
ALONG THIS BOUNDARY. OVER THE NEXT 24 HOURS...EXPECT FOR A
FRONTAL BOUNDARY TO BECOME STATIONARY ACROSS THE NE GULF STATES
SUPPORTING CONVECTION ACROSS THE NORTHERN GULF.

CARIBBEAN SEA...

AN UPPER-LEVEL LOW CENTERED NEAR 19N78W INFLUENCES MUCH OF THE
CARIBBEAN BASIN SUPPORTING SCATTERED CONVECTION ACROSS
CUBA...JAMAICA...HISPANIOLA...AS WELL AS THE CARIBBEAN WATERS
MAINLY W OF 70W. TO THE E...A SURFACE TROUGH PREVAILS S OF
PUERTO RICO EXTENDING FROM 17N66W TO 13N65W. ISOLATED CONVECTION
IS AT ABOUT 100 NM E OF THIS BOUNDARY. SCATTEROMETER DATA
DEPICTS GENTLE TO MODERATE TRADES PREVAILING ACROSS THE BASIN.
EXPECT SIMILAR CONDITIONS TO PREVAIL OVER THE NEXT 24 HOURS.

...HISPANIOLA...

THE UPPER LEVEL-LOW CENTERED ACROSS THE CENTRAL CARIBBEAN IS
SUPPORTING SCATTERED MODERATE CONVECTION ACROSS THE ISLAND. THIS
ACTIVITY WILL CONTINUE THROUGH THE EVENING HOURS. A SIMILAR
WEATHER REGIME WILL PREVAIL OVER THE NEXT 24 HOURS.

ATLANTIC OCEAN...

WATER VAPOR IMAGERY INDICATES AN UPPER-LEVEL TROUGH EXTENDS OVER
THE EASTERN CONUS WITH A BASE REACHING THE OFFSHORE WATERS NEAR
31N80W. THIS TROUGH SUPPORTS A COLD FRONT THAT EXTENDS FROM A
1009 MB LOW CENTERED IN THE NW ATLANTIC REACHING OUR AREA NEAR
31N80W THEN EXTENDS W ACROSS THE FLORIDA PANHANDLE AND THE GULF
STATES. SCATTERED MODERATE CONVECTION PREVAILS IN THE VICINITY
OF THIS FRONT MAINLY N OF 28N AND W OF 69W. TO THE E...A FRONTAL
BOUNDARY WAS ANALYZED ACROSS THE E ATLANTIC AS A WEAKENING COLD
FRONT FROM 31N45W TO 28N34W THEN AS A STATIONARY FRONT FROM THAT
POINT TO 35N26W. ISOLATED CONVECTION IS OBSERVED ALONG THESE
BOUNDARIES. A SURFACE TROUGH EXTENDS FROM 31N23W TO 27N23W. AN
UPPER-LEVEL SHORTWAVE IS DEVELOPING E OF THIS TROUGH SUPPORTING
ISOLATED CONVECTION AFFECTING THE CANARY ISLANDS AND NW AFRICA.
ELSEWHERE...A BROAD AREA OF HIGH PRESSURE PREVAILS ACROSS THE
REMAINDER OF THE BASIN WITH FAIR WEATHER. OVER THE NEXT 24
HOURS...THE COLD FRONT OVER THE W ATLANTIC WILL BECOME
STATIONARY SUPPORTING CONVECTION WHILE THE FRONTAL BOUNDARIES
OVER THE E ATLANTIC WILL DISSIPATE. SURFACE HIGH PRESSURE WILL
CONTINUE TO DOMINATE THE BASIN.

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

$$

ERA
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