Tropical Weather Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
AXNT20 KNHC 101755
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT WED SEP 10 2014

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.

...TROPICAL WAVES...
A TROPICAL WAVE IN THE E ATLANTIC EXTENDS FROM 9N33W TO 19N32W
MOVING W AT 10-15 KT. A SW-NE ELONGATED 1009 MB SURFACE LOW IS
CENTERED ALONG THE WAVE AXIS NEAR 13N32W. MOST CONVECTION IS
OCCURRING ALONG THE SW-NE ORIENTED LOW PRESSURE AXIS WITH
SCATTERED TO MODERATE CONVECTION FROM 11N-18N BETWEEN 30W-37W.

A TROPICAL WAVE IN THE CENTRAL ATLANTIC EXTENDS FROM 10N54W TO
21N53W MOVING W AT 10-15 KT. THIS WAVE IS WELL DEFINED IN
VISIBLE SATELLITE IMAGERY. SSMI TPW IMAGERY SHOWS THE HIGHEST
MOISTURE CONFINED TO THE NORTHERN PORTION OF THE WAVE.
INTERACTION OF THE WAVE...THE MOIST AIRMASS...AND INTERACTION
WITH AN UPPER LOW TO THE NW OF THE WAVE IS HELPING PRODUCE
SCATTERED MODERATE CONVECTION JUST NORTH OF THE WAVE AXIS FROM
21N-24N BETWEEN 51W-54W.

A TROPICAL WAVE EXTENDS FROM CENTRAL GULF NEAR 24N89W...ACROSS
MEXICO AND PORTIONS OF CENTRAL AMERICA...TO THE E PACIFIC NEAR
11N91W. NO DEEP CONVECTION IS NOTED ALONG THE PORTIONS OF THE
WAVE IN THE GULF...OVER MEXICO...AND CENTRAL AMERICA.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM 12N16W TO 14N30W TO 07N49W. THE
ITCZ AXIS EXTENDS FROM 07N49W TO 07N58W. OTHER THAN CONVECTION
MENTIONED IN THE TROPICAL WAVES SECTION ABOVE...SCATTERED
MODERATE CONVECTION IS FROM 6N-14N BETWEEN 14W-27W. ISOLATED
MODERATE CONVECTION IS FROM 7N-10N BETWEEN 39W-41W.

...DISCUSSION...

GULF OF MEXICO... UPPER LEVEL CONFLUENCE BETWEEN UPPER LEVEL
ANTICYCLONE CENTER OVER TX/MEXICO AND SMALL UPPER LOW IN THE BAY
OF CAMPECHE IS HELPING TO INHIBIT CONVECTION ACROSS THE WESTERN
HALF OF THE GULF TODAY. THIS INCLUDES THE SOUTHWESTERN
GULF...WHERE A TROPICAL WAVE MENTIONED IN THE TROPICAL WAVES
SECTION LACKS CONVECTION. AN AREA OF UPPER LEVEL DIFFLUENCE IS
ACROSS THE E GULF BETWEEN THE AFOREMENTIONED UPPER LEVEL
ANTICYCLONE TO THE WEST...AND AN UPPER TROUGH TO THE E OF
FLORIDA. THIS DIFFLUENCE IS COMBINING WITH DEEP LAYER MOISTURE
TO HELP PRODUCE SCATTERED THUNDERSTORMS FROM THE YUCATAN CHANNEL
N TO 28N...E OF 87W. THIS REGION OF DIFFLUENCE AND COINCIDING
SCATTERED THUNDERSTORMS ARE FORECAST TO SHIFT GRADUALLY INTO THE
CENTRAL GULF OVER THE NEXT 48 HOURS. AN EASTWARD MOVING SURFACE
TROUGH OVER THE BAHAMAS MAY BRING ADDITIONAL SHOWERS AND
THUNDERSTORMS TO THE EASTERN GULF THURSDAY AND FRIDAY.

CARIBBEAN SEA...

UPPER LEVEL WESTERLY FLOW DOMINATES THE CENTRAL AND EASTERN
CARIBBEAN. THIS IS OVERRIDING LOW LEVEL EASTERLIES TO PRODUCE A
LARGE AREA OF MODERATE DEEP LAYER SHEAR IN THE PRESENCE OF
RELATIVELY DRY AIR. THESE FACTORS ARE HELPING TO KEEP THE ENTIRE
CENTRAL AND EASTERN CARIBBEAN CONVECTION FREE. THESE FAIR
CONDITIONS ARE EXPECTED TO PERSIST FOR THE NEXT DAY OR TWO. A
BROAD AREA OF UPPER LEVEL DIFFLUENCE IS OCCURRING OVER THE W
CARIBBEAN...BETWEEN A WEAKENING UPPER LOW OVER CUBA NEAR
21N75W...AND ANOTHER SMALL UPPER LOW OVER THE BAY OF CAMPECHE.
THIS DIFFLUENCE IS OCCURRING IN THE PRESENCE OF DEEP LAYER
MOISTURE TO PRODUCE SCATTERED MODERATE TO ISOLATED STRONG
CONVECTION FROM THE N COAST OF PANAMA TO 22N BETWEEN 80W AND
88W. THIS REGION OF DIFFLUENCE WILL SLOWLY WEAKEN OVER THE NEXT
TWO DAYS WHILE DRIER AIR TRIES TO MAKE ITS WAY WEST INTO THE
AREA. THIS SHOULD BRING ABOUT A GRADUAL DECREASE IN CONVECTION
OVER THE W CARIBBEAN OVER THE NEXT 48 HOURS.

...HISPANIOLA...
CYCLONIC UPPER LEVEL FLOW IS SPREADING ACROSS THE AREA FROM A
LARGE UPPER LOW IN THE ATLANTIC NEAR 26N59W. HISPANIOLA IS FAR
ENOUGH REMOVED FROM THE UPPER LOW THAT CONVECTION FROM THE UPPER
LOW IS NOT AFFECTING THE AREA. THE UPPER LOW IS EXPECTED TO MOVE
SOUTHWEST...NEARER TO HISPANIOLA OVER THE NEXT 48 HOURS. THIS
COULD BRING AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY TO
THE AREA BY FRIDAY.


ATLANTIC OCEAN...
A LARGE UPPER LOW IS CENTERED NEAR 26N59W DRIFTING
SOUTHWESTWARD. SCATTERED MODERATE CONVECTION IS OCCURRING WITHIN
300NM OF THE LOW FROM 24N-31N BETWEEN 55W-64W. A SURFACE TROUGH
OVER THE CENTRAL BAHAMAS IS NEAR 24N77W TO 29N74W. THERE ARE
INDICATIONS IN VISIBLE SATELLITE IMAGERY THAT A CLOSED LOW MAY
BE DEVELOPING IN THE AREA. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ARE OCCURRING FROM 25N-29N BETWEEN 72W-77W. THIS
TROUGH IS EXPECTED TO DRIFT WEST TO NORTHWEST OVER THE NEXT 24
HOURS WITH ONGOING SHOWERS AND THUNDERSTORMS EXPECTED TO
CONTINUE WITH THE TROUGH. OTHER DEEP CONVECTION IN THE ATLANTIC
IS ASSOCIATED WITH TROPICAL WAVES MENTIONED IN THE TROPICAL
WAVES SECTION.

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

$$
LATTO


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.