[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271112
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU JUN 27 2013

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.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 14N44W TO 02N46W MOVING WEST NEAR 10 KT.
THE WAVE COINCIDES WITH A SURGE OF DEEP LAYER MOISTURE PRESENT
IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE
CONVECTION IS FROM 03N-12N BETWEEN 39W-49W.

TROPICAL WAVE IS MOVING THROUGH THE CENTRAL CARIBBEAN ALONG
21N71W TO 12N71W MOVING WEST NEAR 5 KT. A SURGE OF MODERATE
MOISTURE IS AT THE LOWER LEVELS EAST OF THE WAVE AXIS AND WRAPS
AROUND THE NORTHERN PORTION OF THE AXIS. DRIER AIR HAS UNDERCUT
THIS MOISTURE TO THE NORTH SO THAT NO DEEP CONVECTION IS AROUND
THE SOUTHERN PORTION OF THE WAVE. SCATTERED MODERATE CONVECTION
IS S OF HAITI FROM 17N-18N BETWEEN 72W-75W...ISOLATED
SHOWERS/THUNDERSTORMS ARE OVER THE NORTHERN PUERTO RICO AND LA
HISPANIOLA.

WEAK TROPICAL WAVE IS MOVING INTO THE WESTERN CARIBBEAN ALONG
22N82W TO 10N82W MOVING WEST NEAR 5 KT. THE WAVE HAS A WEAK
MOISTURE SIGNAL WITH IT OVER THE NORTHERN PORTION AND A STRONGER
SIGNAL TO THE SOUTH WITH RELATIVELY DRY AIR NEAR THE CENTRAL
PORTION. SCATTERED MODERATE CONVECTION IS OVER WESTERN CUBA
EXTENDING WITHIN 50 NM S OF THE COASTLINE BETWEEN 80W-84W.
CLUSTERS OF MODERATE CONVECTION AND THUNDERSTORMS ARE S OF 12N
WEST OF 79W IN THE SOUTHERN CARIBBEAN.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM THE COASTAL WEST AFRICA NEAR
12N16W TO 08N23W. THE ITCZ BEGINS NEAR 08N23W AND CONTINUES
ALONG 05N33W 07N42W. CLUSTERS OF MODERATE/STRONG CONVECTION ARE
FROM 03N-08N BETWEEN 27W-37W AND FROM 03N-12N BETWEEN 38W-49W.
ISOLATED SHOWERS/THUNDERSTORMS ARE FROM 08N-11N EAST OF 19W.

...DISCUSSION...

GULF OF MEXICO...
THE AZORES HIGH EXTENDS A RIDGE AXIS SW ALL THE WAY THROUGH THE
GULF WHICH IS GENERATING RETURN FLOW IN THE RANGE OF 10-15 KT
ACROSS THE BASIN...EXCEPT IN THE BAY OF CAMPECHE WHERE A MAXIMUM
OF 25 KT IS POSSIBLE AS INDICATED BY THE LATEST ASCAT PASS.
ALOFT...AN UPPER LEVEL TROUGH SPREADS OVER THE GULF WITH AN
EMBEDDED CYCLONIC CIRCULATION W OF 88W. THE UPPER TROUGH IS
PROVIDING MOIST SOUTHWESTERLY AND DIFFLUENT FLOW ALOFT ACROSS
MOST OF THE S-SE GULF. THE UPPER CYCLONIC CIRCULATION IS
SUPPORTING A SURFACE TROUGH IN THE BAY OF CAMPECHE FROM 22N90W
TO 18N93W WHICH IS GENERATING ISOLATED SHOWERS S OF 23N EAST OF
95W. WITHIN A 24 HOUR PERIOD A HIGH PRESSURE WILL BUILD NEAR THE
NORTHERN CENTRAL GULF...OTHERWISE LITTLE CHANGE IS EXPECTED.

CARIBBEAN SEA...
TWO TROPICAL WAVES ARE ACROSS THE CARIBBEAN. THE FIRST IS NEAR
83W WHERE DRY AIR IS LIMITING CONVECTION S OF 21N. SCATTERED
MODERATE CONVECTION IS OVER WESTERN CUBA EXTENDING WITHIN 50 NM
S OF THE COASTLINE BETWEEN 80W-84W.  CLUSTERS OF MODERATE
CONVECTION AND THUNDERSTORMS ARE S OF 12N WEST OF 79W IN THE
SOUTHERN CARIBBEAN ASSOCIATED WITH THE MONSOON TROUGH. THE
SECOND WAVE IS APPROACHING 72W. MOISTURE WITH THIS WAVE IS
MAINLY TO THE NORTH AND EAST OF THE AXIS. SCATTERED MODERATE
CONVECTION IS S OF HAITI FROM 17N-18N BETWEEN 72W-75W...ISOLATED
SHOWERS/THUNDERSTORMS ARE OVER THE NORTHERN PUERTO RICO AND LA
HISPANIOLA. ALOFT...BROAD UPPER RIDGING COVERS THE MAJORITY OF
THE BASIN. TRADEWIND FLOW OF 15-20 KT IS THROUGHOUT THE AREA.
BOTH WAVES ARE EXPECTED TO REMAIN WEAK/VANISH WHILE CONTINUING
MOVING WEST WITHIN THE NEXT 48 HOURS.

HISPANIOLA...
CURRENT DRY SURFACE CONDITIONS ARE INDICATED ACROSS THE ISLAND
IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE
CONVECTION IS S OF HAITI FROM 17N-18N BETWEEN 72W-75W ASSOCIATED
WITH THE WEAK TROPICAL WAVE MOVING OVER THE ISLAND. THE WAVE
AXIS IS EXPECTED TO EXIT HAITI THURSDAY AFTERNOON BUT TRAILING
MOISTURE ASSOCIATED WITH THE WAVE IS EXPECTED TO ENHANCE
RAINSHOWERS THROUGHOUT THURSDAY EVENING.

ATLANTIC OCEAN...
BROAD SURFACE RIDGING COVERS THE WEST ATLC AROUND A 1021 MB HIGH
NEAR 29N62W. ALOFT...AN UPPER RIDGE IS ALONG 78W...WHILE AN
UPPER LOW SPINS TO THE EAST NEAR 25N63W. DIFFLUENT FLOW S OF
THAT LOW IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS FROM 18N-
21N BETWEEN 62W-68W. OTHERWISE...BROAD SURFACE RIDGING DOMINATES
THE REMAINDER OF THE BASIN N OF 13N EXTENDING FROM A 1038 MB
HIGH NEAR 46N20W. THE METEOSAT-9 SAL TRACKING PRODUCT DEPICTS A
TONGUE OF SAL DRY AIR EXTENDING FROM THE COAST OF AFRICA TO NEAR
58W.

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

$$
NR


This weather bulletin was brought to you by:
www.nashvilleweather.net