[Tropical] Tropical Weather Discussion

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AXNT20 KNHC 141742
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT FRI SEP 14 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN
SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE
AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION
IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...
WEATHER OBSERVATIONS...AND RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...SPECIAL FEATURES...

INGRID IS MOVING SLOWLY OVER OPEN WATERS AND TEMPORARILY
STRENGTHENS. TROPICAL STORM INGRID IS CENTERED NEAR 15.2N 50.0W
AT 14/1500 UTC OR ABOUT 655 NM...1210 KM...EAST OF THE LESSER
ANTILLES MOVING WEST-NORTHWEST AT 6 KT. ESTIMATED MINIMUM
CENTRAL PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 40
KT WITH GUSTS TO 50 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER
AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS.
FIXES FROM A NOAA RECONNAISSANCE PLANE INDICATE THAT THE CENTER
OF INGRID IS CLOSER TO CONVECTION. HOWEVER...SATELLITE IMAGERY
SHOWS THAT THE CLOUD PATTERN HAS ALREADY BEGUN TO DETERIORATE
THANKS TO A STRONGER THAN NORMAL SHEARED ENVIRONMENT. SMALL
CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION IS NEAR THE
CENTER OF INGRID. THE OFFICIAL NHC FORECAST KEEPS INGRID AS A
TROPICAL DEPRESSION DURING THE NEXT 5 DAYS BUT IT IS POSSIBLE
THAT INGRID WILL NOT LAST THROUGH THIS WHOLE PERIOD.

...TROPICAL WAVES...

TROPICAL WAVE IS TITLED FROM 16N26W TO 3N28W MOVING W 10-15
KT. A 1010 MB LOW IS ANALYZED ALONG THE WAVE AXIS NEAR
10N...CONFIRMED BY A BROAD AREA OF CYCLONIC TURNING IN AN
EARLIER QSCAT PASS. OVERALL...THIS WAVE HAS CHANGED LITTLE OVER
THE PAST 24 HOURS WITH CONVECTION LIMITED AND DISORGANIZED. A
CURVED BAND OF SHOWERS WITH ISOLATED TSTMS IS ON THE NORTHERN
END OF WAVE AXIS. THE REMAINDER OF CONVECTION IS WITHIN THE ITCZ
AXIS. THE UW-CIMSS TPW ANIMATION SHOWS A WELL DEFINED WIDE
MOISTURE PLUME ASSOCIATED WITH THIS WAVE...MAKING IT EASY TO
TRACK.

TROPICAL WAVE IS ALONG 41W S OF 17N MOVING W 5-10 KT. MOST OF
CONVECTION ASSOCIATED WITH THE WAVE IS WITHIN THE ITCZ. THIS
WAVE IS STILL SHOWING AN INVERTED V-PATTERN ON VIS SAT IMAGERY.
SCATTERED MODERATE CONVECTION IS FROM 4N-8N BETWEEN 38W-42W.

TROPICAL WAVE IS ALONG 63W S OF 19N MOVING W 10-15 KT. THE SSMI
DERIVE TPW INDICATES THE PRESENCE OF THIS WAVE AS WELL AS SFC
DATA. THE WAVE IS GENERATING SOME SHOWER ACTIVITY OVER THE
SOUTHERN WINDWARD ISLANDS AND NE VENEZUELA.

TROPICAL WAVE IS OVER THE YUCATAN PENINSULA AND GUATEMALA INTO
THE EPAC WHERE THERE IS A BROAD AREA OF CYCLONIC TURNING AND
CLUSTERS OF MODERATE TO ISOLATED STRONG CONVECTION.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 9N13W 11N25W 6N35W 10N45W 10N60W.
BESIDES FOR THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES
AND T.S. INGRID...NO SIGNIFICANT CONVECTION.

DISCUSSION...

THE GULF OF MEXICO...
A BAND OF SHOWERS WITH EMBEDDED TSTMS IS OVER THE NW CORNER OF
THE GULF ASSOCIATED WITH HUMBERTO'S TRAILING TROUGH. THIS TROUGH
EXTENDS FROM SE LOUISIANA TO THE DEEP SOUTH. ISOLATED SHOWERS
ARE SEEN OVER THE REMAINDER OF THE GULF MAINLY NORTH OF 24N. A
SFC RIDGE FROM THE ATLC DOMINATES THE EASTERN GULF AND THE STATE
OF FLORIDA. ALOFT...AN UPPER RIDGE ANCHORED ON A HIGH OVER
NORTHERN FLORIDA DOMINATES MOST OF THE GULF WHILE AN UPPER
TROUGH LIES OVER CENTRAL TEXAS. THIS UPPER TROUGH IS SUPPORTING
A COLD FRONT THAT IS FORECAST TO MOVE OFF THE TEXAS COAST LATE
THIS AFTERNOON. A WEDGE OF DRY AIR IS EVIDENT ON WATER VAPOR
IMAGERY BETWEEN 22N-25N DUE TO A SLIGHTLY CONFLUENT PATTERN
BETWEEN THE RIDGE AND TROUGHING TO THE S AND E. MOISTURE
INCREASES AGAIN IN THE BAY OF CAMPECHE AND SOUTH MEXICO DUE TO
THE PRESENCE OF AN INVERTED TROUGH. SFC WINDS ARE MOSTLY LIGHT
FROM THE SE AND S...EXCEPT SW TO W IN THE FAR NW CORNER OF THE
GULF. TOTAL RAINFALL AMOUNTS UP TO 14 INCHES ARE ASSOCIATED WITH
HUMBERTO THROUGH 700 AM CDT FRIDAY IN TEXAS.

THE CARIBBEAN SEA...
A DIFFLUENT PATTERN ALOFT RELATED TO AN UPPER HIGH LOCATED JUST
OFF THE COLOMBIA COAST COUPLED WITH THE EPAC ITCZ AND THE
SEMI-PERMANENT COLOMBIAN LOW IS HELPING TO DEVELOP CLUSTERS OF
MODERATE TO ISOLATED STRONG CONVECTION ACROSS THE SW CARIBBEAN S
OF 12N W OF 75W. THIS CONVECTIVE ACTIVITY IS ALSO AFFECTING
PARTS OF NICARAGUA...COSTA RICA AND PANAMA. SIMILAR CONVECTION
IS FOUND ON THE EPAC SIDE JUST SOUTH OF COSTA RICA/PANAMA.
FAIRLY STRONG UPPER WLY FLOW...VERY UNFAVORABLE FOR TROPICAL
CYCLONE DEVELOPMENT HAS SET UP ABOVE THE MAJORITY OF THE BASIN
BETWEEN THE AFOREMENTIONED HIGH OVER COLOMBIA AND UPPER
TROUGHING OVER HISPANIOLA. THIS FLOW IS TRANSPORTING DEBRIS HIGH
LEVEL CLOUDINESS ACROSS THE WESTERN-CENTRAL CARIBBEAN. THE AIR
DRIES OUT E OF 75W...WITH THE EXCEPTION OF SOME MOISTURE
ASSOCIATED WITH THE UPPER TROUGH OVER HISPANIOLA AND THE
TROPICAL WAVE ALONG 63W. TYPICAL TRADE WIND SHOWERS ARE ALSO
SEEN OVER THE EASTERN CARIBBEAN.

THE ATLANTIC OCEAN...
TROPICAL STORM INGRID IS THE MAIN FEATURE OF INTEREST ACROSS THE
DISCUSSION AREA. FOR MORE DETAILS REFER TO THE SPECIAL FEATURE
SECTION ABOVE. OTHER REGIONS OF ACTIVE WEATHER ARE AN AREA OF
SHOWERS AND TSTMS LOCATED N OF HISPANIOLA WHICH IS ASSOCIATED
WITH A SFC TROUGH AND AN UPPER LOW...AND THE SECOND ONE...
DETACHED FROM THE TROPICAL WAVE LOCATED ALONG 41W IS ALSO
ASSOCIATED WITH A SFC TROUGH ALONG 39W/40W FROM 20N-31N. THE
REMAINDER OF THE SFC PATTERN IS DOMINATED BY TYPICAL SUBTROPICAL
RIDGING.

ALOFT...A COMPLEX PATTERN REMAINS IN PLACE ACROSS THE CENTRAL
AND W ATLC. THE ERN PERIPHERY OF THE UPPER HIGH CENTERED OVER N
FLORIDA  COVERS THE W ATLC WEST OF 70W. A CYCLONIC FLOW
DOMINATES THE AREA BETWEEN 45W-70W WHERE THERE ARE A PAIR OF
SPINNING UPPER LOWS...ONE IS NEAR 26N66W THE OTHER ONE IS NEAR
25N52W. THE TROPICAL E AND CENTRAL ATLC IS STILL DOMINATED BY A
E-W RIDGE COVERING THE AREA FROM THE LESSER ANTILLES EWD WITH A
MEAN AXIS ALONG 15N WITH SEVERAL EMBEDDED ANTICYCLONES.

$$
GR



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