[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 081805
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT SUN JUL 08 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
1730 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 40W/41W FROM 2N-14N MOVING W NEAR 15
KT. THIS WAVE WAS POSITIONED SLIGHTLY W OF WHERE CONTINUITY
WOULD HAVE TAKEN IT...BASED ON THE LOW TO MID LEVEL CYCLONIC
TURNING NOTED FROM 9N-14N BETWEEN 37W-43W...AND THE SURGE OF
SCATTERED SHOWERS/TSTMS FROM 2N-9N BETWEEN 39W-45W. DEEP
CONVECTION REMAINS MINIMAL THOUGH. CONVECTION HAS FLARED UP
FURTHER W ALONG THE ITCZ BETWEEN 49W-57W AS DISCUSSED BELOW.
BASED ON SATELLITE HOVMOLLER DIAGRAMS...THERE MAY BE ANOTHER
WEAK TROPICAL WAVE IN THE VICINITY OF 51W WHICH WILL BE
REEVALUATED FOR THE 1800 UTC MAP.

A TROPICAL WAVE IS ALONG 65W SOUTH OF 15N MOVING W 10-15 KT.
THIS WAVE HAS LOST MUCH OF ITS IDENTITY OVER THE LAST COUPLE OF
DAYS...AND NOW IS MAINLY JUST A SURGE OF MOISTURE AS DEPICTED
WELL BY SSMI DERIVED PRECIPITABLE WATER. DEEP CONVECTION REMAINS
MINIMAL ON BOTH SIDES OF THE AXIS.

A TROPICAL WAVE IN THE CARIBBEAN IS ALONG 81W MOVING W NEAR 15
KT. SCATTERED SHOWERS AND TSTMS...ALSO ENHANCED BY THE
ITCZ...ARE OVER THE SW CARIBBEAN AND CENTRAL AMERICA S OF 13N.
LOW CLOUD MOTIONS SHOW SOME CYCLONIC TURNING S OF CUBA...N OF
17N BETWEEN 78W-84W...BUT AM NOT ENTIRELY CONVINCED THIS IS DUE
TO THE WAVE. REGARDLESS...LIGHTNING DATA SUPPORTS ISOLATED TSTMS
IN THIS REGION.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 8N11W 5N25W 8N38W 9N50W 7N60W.
ISOLATED MODERATE CONVECTION IS WITHIN 90NM EITHER SIDE OF THE
AXIS E OF 15W...AND BETWEEN 19W-29W. AS MENTIONED
ABOVE...SCATTERED MODERATE IS WITHIN 90NM OF THE AXIS BETWEEN
48W-59W.

...DISCUSSION...
GULF OF MEXICO...
A WEAK 1017 MB HIGH IS OVER THE CENTRAL GULF NEAR 26N88W. THIS
IS EXPECTED TO CONTINUE DISSIPATING THROUGH TONIGHT AS THE WRN
PORTION OF THE ATLC RIDGE BUILDS W. HOWEVER...LEFTOVER LOW LEVEL
CONFLUENCE BETWEEN THE TWO HIGHS IS PRODUCING WEAK TROUGHING IN
THE SE GULF. THIS WAS PLACED ALONG 25N82W 23N88W AT 8/1500
UTC...AND IS SUPPORTING SCATTERED SHOWERS/ISOLATED TSTMS WITHIN
60NM EITHER SIDE OF THE TROUGH. THIS ACTIVITY ALSO AIDED BY
UPPER DIFFLUENCE BETWEEN AN UPPER HIGH JUST W OF TAMPA AND BROAD
TROUGHING IN THE CARIBBEAN. A PAIR OF THIN LINES OF LOW CLOUDS
ARE JUST S OF THE FL PANHANDLE...ASSOCIATED WITH LOW LEVEL
CONFLUENCE S AND AHEAD OF THE LOW SPINNING OVER ALABAMA/GEORGIA.
FAIR WEATHER AND LIGHT TO MODERATE WINDS AROUND RIDGING
DOMINATE ELSEWHERE.

CARIBBEAN SEA...
OUTSIDE OF THE WEATHER MENTIONED ABOVE WITH THE TROPICAL WAVES
THE BASIN IS FAIRLY QUIET. MODERATE TO FRESH TRADES ARE IN PLACE
S OF AN ATLC SFC RIDGE...AND EXPECTED TO PERSIST THROUGH
MIDWEEK. THE TRADES ARE ALLOWING TYPICAL PATCHES OF LOW LEVEL
MOISTURE WITH EMBEDDED ISOLATED SHOWERS TO PUSH W ACROSS THE
AREA. THE UPPER PATTERN IS LARGELY DOMINATED BY ELONGATED
TROUGHING THAT EXTENDS E/W ALONG 15/16N.

ATLANTIC OCEAN...
AN AREA OF SCATTERED SHOWERS/TSTMS REMAINS OFF THE FLORIDA
COAST...WITHIN 120NM EITHER SIDE OF A LINE FROM PALM BEACH TO
32N74W. IN ADDITION TO THE LOW LEVEL CONFLUENCE THAT HAS HUNG
AROUND IN THIS VICINITY THE LAST FEW DAYS...THE ACTIVITY IS
BEING SUPPORTED BY UPPER DIFFLUENCE AROUND AN UPPER RIDGE AXIS.
THE REMAINDER OF THE DISCUSSION AREA IS BY AND LARGE DOMINATED
BY A TYPICAL SUMMERTIME SFC RIDGE AXIS ANCHORED BY A 1032MB HIGH
NEAR 42N22W. THIS IS PRODUCING ABUNDANT FAIR WEATHER AND LIGHT
TO MODERATE TRADES E OF 70W. THE WEAK TROUGHING/LOW LEVEL
CONFLUENCE OVER THE WRN ATLC WILL GRADUALLY DISSIPATE/LIFT NE
OVER THE NEXT DAY OR SO AS THE ATLC RIDGE BUILDS W ACROSS
FLORIDA AND INTO THE GULF. ELSEWHERE ALOFT ON THE LARGE
SCALE...RIDGING CONTINUES TO DOMINATE THE FAR W AND E PORTIONS
OF THE DISCUSSION AREA WITH BROAD TROUGHING OVER THE CENTRAL
ATLC. OTHER SMALLER SCALE UPPER FEATURES ARE EMBEDDED IN THIS
PATTERN BUT ARE NOT GENERATING SIGNIFICANT WEATHER.

$$
WILLIS


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