[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271043
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON JUN 27 2005

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHEASTERN
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...

EASTERN ATLANTIC OCEAN TROPICAL WAVE ALONG 31W S OF 15W MOVING
WEST 10-15 KT.  IR SATELLITE IMAGERY SUGGESTS A POSITION FURTHER
E NEAR 30W.  HOWEVER...GIVEN THE UNCERTAINTY OF LOCATING WAVES
AT NIGHT WITH IR IMAGERY...THE POSITION IS HELD RATHER THAN
REPOSITIONED.  REPOSITIONING MAY BE REQUIRED LATER TODAY ONCE
VISIBLE IMAGERY BECOMES AVAILABLE.

CENTRAL ATLANTIC OCEAN TROPICAL WAVE IS ALONG 45W S OF 15N
MOVING WEST 10-15 KT. THIS WAVE CONTINUES TO DEMONSTRATE A
WELL-DEFINED SIGNATURE IN BOTH SATELLITE IMAGERY AND QUIKSCAT
DATA.  IN FACT...A WEAK LOW LEVEL CIRCULATION IS NOTED IN
SATELLITE IMAGERY NEAR 10N.  DEEP CONVECTION HAS BEEN INCREASING
OVERNIGHT WITH A SMALL AREA OF SCATTERED MODERATE ACTIVITY
CURRENTLY FROM 9N-12N BETWEEN 44W-48W.

EASTERN CARIBBEAN SEA TROPICAL WAVE IS ALONG 72W S OF 15N
MOVING WEST 10-15 KT. THE WAVE HAS LITTLE OR NO SATELLITE
SIGNATURE. THE CURRENT POSITION IS BASED UPON EXTRAPOLATION AND
NEARBY UPPER AIR TIMESECTIONS.  THE WAVE IS CURRENTLY LOCATED
WITHIN A REGION OF UPPER LEVEL CONFLUENCE AND DRY AIR TO THE
WEST OF AN UPPER LOW NEAR THE LEEWARD/WINDWARD ISLANDS.  THIS
ENVIRONMENT IS SUPPRESSING DEEP CONVECTION.

CARIBBEAN SEA TROPICAL WAVE IS ALONG 85W S OF 15N MOVING WEST 18
KT.  THE WAVE IS ACCOMPANIED BY AN AREA OF SCATTERED STRONG
CONVECTION WITHIN 75 NM EITHER SIDE OF WAVE AXIS FROM 13N-18N.
THIS ACTIVITY WILL AFFECT PORTIONS OF HONDURAS/NICARAGUA DURING
THE NEXT FEW HOURS AS IT MOVES WESTWARD.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 11N10W 6N20W 9N45W 6N60W THEN OVER
N PORTIONS OF VENEZUELA AND COLOMBIA.  WIDELY SCATTERED MODERATE
CONVECTION IS WITHIN 100 NM S OF THE ITCZ FROM THE COAST OF
AFRICA TO 30W.  SCATTERED MODERATE CONVECTION IS WITHIN 250 NM N
OF THE ITCZ FROM 53W-57W.

...DISCUSSION...

GULF OF MEXICO...
RATHER MOIST AND UNSETTLED PATTERN HAS ONCE AGAIN BECOME
ESTABLISHED OVER THE E GLFMEX AND FLORIDA COURTESY OF AN UPPER
LEVEL TROUGH FROM TENNESSEE SW OVER LOUISIANA TO TAMPICO
MEXICO AND THE N EXTENT OF A TROPICAL WAVE STRETCHING FROM THE W
YUCATAN PENINSULA TO CENTRAL FLORIDA NEAR TAMPA.  THE WAVE IS
ACCOMPANIED BY SIGNIFICANT DEEP LAYERED MOISTURE WITH S FLORIDA
SOUNDINGS SHOWING PRECIPITABLE WATER VALUES SURGING ABOVE 2
INCHES AS THE WAVE PASSED.  THIS INCREASE IN MOISTURE COUPLED
WITH AN INCREASINGLY DIFFLUENT UPPER PATTERN IS PRODUCING
WIDESPREAD CLOUDINESS AND SHOWERS/TSTMS S AND E OF THE UPPER
TROUGH AXIS.  THE STRONGEST OF THIS ACTIVITY CURRENTLY RESIDES
JUST E OF THE WAVE AXIS AFFECTING THE YUCATAN PENINSULA...
FLORIDA STRAITS...AND S FLORIDA.  THIS ACTIVITY WILL GRADUALLY
SPREAD NWD OVER THE REMAINDER OF FLORIDA AND E GLFMEX DURING THE
NEXT 24 HOURS PRODUCING LOCALLY HEAVY RAINFALL AND POSSIBLE
FLOODING OVER THE ALREADY RAIN SOAKED FLORIDA PENINSULA.

CARIBBEAN SEA...
PRIMARY FOCUS TODAY IS OVER THE W CARIBBEAN AND CENTRAL
AMERICA WHERE DEEP LAYERED MOISTURE POOLING ASSOCIATED WITH A
PAIR OF TROPICAL WAVES COUPLED WITH DIFFLUENT FLOW ALOFT IS
PRODUCING WIDESPREAD CLOUDINESS AND SHOWERS/TSTMS PRIMARILY FROM
W HONDURAS AND EL SALVADOR WESTWARD INTO S MEXICO E OF THE
ISTHMUS OF TEHUANTEPEC.  THE STRONGEST OF THIS ACTIVITY IS
CURRENTLY LOCATED OVER GUATEMALA AND BELIZE BUT ADDITIONAL
ACTIVITY IS MOVING ONSHORE HONDURAS/NICARAGUA.  STRONG
SHOWERS/TSTMS ARE ALSO NOTED OVER THE YUCATAN CHANNEL.  THIS
ACTIVITY SHOULD GRADUALLY SPREAD WESTWARD DURING THE NEXT 24
HOURS AS A MUCH DRIER AIRMASS CURRENTLY OVER THE CENTRAL
CARIBBEAN OVERSPREADS THIS AREA.  OVER THE CENTRAL AND E
CARIBBEAN...MIDDLE TO UPPER LEVEL CONFLUENCE AND DRY/STABLE AIR
W OF AN UPPER LOW NEAR 13N62W DOMINATES THE AREA E JAMAICA.
THIS PATTERN IS SUPPRESSING DEEP CONVECTIVE ACTIVITY SAVE SOME
WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS CURRENTLY OVER THE
NE CARIBBEAN MAINLY N OF 13N E OF 70W.  THE PATTERN WILL BECOME
MORE UNSTABLE OVER THE E CARIBBEAN DURING THE NEXT 2 DAYS WITH
INCREASING CLOUDINESS AND SHOWERS/TSTMS AS THE UPPER LOW MOVES
WESTWARD AND DEEP-LAYERED MOISTURE RETURNS.

ATLANTIC OCEAN...
THE UPPER LEVEL PATTERN CONTINUES TO AMPLIFY AS A STRONG MIDDLE
TO UPPER LEVEL RIDGE OVER THE W CARIBBEAN BUILDS NEWD OVER
FLORIDA INTO THE W ATLC AND A TROUGH SHARPENS OVER THE CENTRAL
ATLC FROM 32N53W TO ROUGHLY 20N61W.  RESULTING FLOW HAS BECOME
LESS DIFFLUENT OVER THE W ATLC WATERS E OF THE BAHAMAS WITH
DECREASING CLOUDINESS AND SHOWER/TSTM ACTIVITY.  WIDELY
SCATTERED SHOWERS AND TSTMS CONTINUE FROM THE CENTRAL BAHAMAS
WESTWARD OVER S FLORIDA COURTESY OF A TROPICAL WAVE IN THE E
GLFMEX BUT THIS ACTIVITY SHOULD MOVE W OF THE AREA DURING THE
NEXT 12-24 HOURS.  WATER VAPOR IMAGERY SHOWS THAT A LARGE UPPER
LOW HAS FORMED NEAR 30N55W WHICH WILL RETROGRADE WESTWARD ALONG
29N/30N REACHING 60W TONIGHT.  CONFLUENT FLOW AND SUBSIDENCE
OVER THE W SIDE OF THE UPPER LOW WILL PRODUCE DRYING ALOFT AND
TRANQUIL WEATHER OVER THE W ATLC THROUGH THE NEXT 2 DAYS. E OF
THE UPPER LOW...DIFFLUENT FLOW ALOFT IS PRODUCING A LINE OF
WIDELY SCATTERED SHOWERS/TSTMS WITHIN 100 NM EITHER SIDE OF A
SURFACE TROUGH FROM 31N50W TO 27N51W TO THE N LEEWARD ISLANDS.
THIS ACTIVITY SHOULD MARCH SLOWLY WESTWARD WITH THE RETROGRADING
UPPER LOW AND BECOME PRIMARILY FOCUSED N OF 25N BY TUE. OVER THE
E ATLC...BROAD UPPER LEVEL TROUGH COVERS THE AREA N OF 20N E OF
40W.  OVER THE TROPICAL ATLC....A WELL-DEFINED E/W ORIENTED
UPPER LEVEL RIDGE EXTENDS ALONG 17N/18N BETWEEN AFRICA AND THE
LESSER ANTILLES.  AS A RESULT...DEEP-LAYERED ELY FLOW DOMINATES
THE TROPICAL BELT S OF ABOUT 15N.

$$
RHOME





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