[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 180603
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST THU JAN 18 2007

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...
CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...
NORTHEASTERN 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0545 UTC.

...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 5N9W 3N30W 2N51W. ISOLATED CLUSTERS
OF MODERATE CONVECTION ARE WITHIN 90NM OF THE AXIS BETWEEN
17W-22W AND BETWEEN 25W-32W. SCATTERED MODERATE FROM EQ-5N
BETWEEN 37W-45W...AND FROM 3N-6N BETWEEN 45W-55W.

...DISCUSSION...
GULF OF MEXICO...
THIS EVENINGS WV IMAGERY CONTINUES TO SHOW SUBTROPICAL JET
SPREADING SIGNIFICANT AMOUNT OF MID TO UPPER MOISTURE FROM THE
NE PAC...THROUGH NRN MEXICO...TEXAS...AND CLIPPING THE NRN GULF
WATERS. MUCH DRIER AIR IS PRESENT SE OF A LINE FROM TAMPICO
MEXICO TO TAMPA FLORIDA. UPPER PATTERN REMAINS DOMINATED BY
RIDGING. SHORTWAVE IR IMAGERY DEPICTS BROKEN TO OVERCAST LOW
CLOUDS BEHIND THE NOW STATIONARY SFC FRONTAL BOUNDARY...WHICH AS
OF 0300 UTC EXTENDS FROM SOUTH FLORIDA TO 25N85W W TO
25N94W...AND THEN EXTENDS S THROUGH THE MIDDLE BAY OF CAMPECHE
TO NEAR VILLAHERMOSA MEXICO. LIGHT RAIN CAN BE EXPECTED BEHIND
THE FRONT WITH THE ISENTROPIC LIFT OCCURRING. STRONG 1042 MB
HIGH PRESSURE BUILDING INTO THE GULF FROM ITS CENTER NEAR THE
JERSEY SHORE IS PRODUCING MODERATE E TO NE WINDS ACROSS THE
GULF...EXCEPT MORE NLY FAR WRN PORTION. WINDS/SEAS EXPECTED TO
CONTINUE TO BACK OFF DURING THE DAY THU AS FRONT CONTINUES TO
WEAKEN. HOWEVER...NE WINDS AND WIND WAVES MAY INCREASE AGAIN
ESPECIALLY NW PORTION FRI AND INTO THE WEEKEND AS LINGERING
TROUGH INTERACTS WITH REINFORCING CONTINENTAL HIGH PRESSURE.

CARIBBEAN SEA...
EXTENSIVE DRY AIR IN THE MID TO UPPER LEVELS CONTINUES TO
SUPPRESS CONVECTION OVER THE ENTIRE CARIBBEAN. MODERATE TO
STRONG TRADE WINDS ALSO CONTINUE OVER THE CARIBBEAN BASIN WITH
THE MAXIMA REMAINING NEAR THE COLOMBIAN COAST AROUND 30 KT. THE
TRADES ARE ADVECTING TYPICAL PATCHES OF LOW LEVEL MOISTURE WITH
EMBEDDED SHOWERS ACROSS THE AREA. SIMILAR CONDITIONS EXPECTED
ACROSS THE CARIBBEAN THROUGH THE WEEKEND.

ATLANTIC OCEAN...
UPPER RIDGE IS BUILDING INTO THE SW NORTH ATLC BEHIND A
WEAKENING UPPER TROUGH. THIS IS ADVECTING HIGH CLOUDS/MOISTURE
EWD FROM THE SE US COAST INTO THE ATLC WATERS N OF 26N W OF 60W.
SIGNIFICANT DRY UPPER AIR IS OVER THE SW NORTH ATLC S OF 26N
THROUGH THE CARIBBEAN. 1042 MB HIGH PRESSURE IS BUILDING INTO
THE W ATLC BEHIND THE COLD FRONT THAT ENTERS THE AREA AT 32N57W
AND CONTINUES SW THROUGH THE NRN BAHAMAS. OVERCAST LOW
CLOUDS/LIGHT RAIN SEEN OVER THE AREA BEHIND THE FRONT...IN
ADDITION TO MODERATE TO STRONG NE WINDS/WAVES. ASSOCIATED
MODERATE NLY SWELL WILL SPREAD E THROUGH THE AREA AS
WELL...PEAKING IN THE BAHAMAS TONIGHT AND AT EXPOSED PUERTO RICO
BEACHES DURING SAT...THEN SUBSIDING FROM W TO E. ELSEWHERE IN
THE SW ATLC...SFC LOW TO DEVELOP OFF NRN FLORIDA LATER TODAY
WILL SWING COLD FRONT THROUGH THE AREA DURING FRI. CENTRAL ATLC
IS DOMINATED BY THE 1016 MB SFC LOW NEAR 23N51W. THIS HAS A
MERIDIONAL SFC TROUGH WITH IT FROM 16N-29N...AND IS A REFLECTION
OF THE UPPER TROUGH EXTENDING THROUGH THE AREA. ASSOCIATED
SCATTERED MODERATE CONVECTION IS FROM 20N-26N BETWEEN 45W-52W.
ISOLATED PATCHES OF MODERATE CONVECTION ARE ELSEWHERE FROM
11N-20N BETWEEN 38W-48W. ANOTHER UPPER LOW IS OVER THE E ATLC
NEAR 22N27W...THAT ALSO HAS SIGNIFICANT MOISTURE WITH EMBEDDED
SHOWERS MAINLY TO ITS E FROM 11N-26N BETWEEN AFRICA AND 27W.
THERE MAY BE A WEAK REFLECTION OF THIS AT THE SFC...THOUGH THE E
ATLC IS GENERALLY DOMINATED BY MODERATE E TO NE WINDS S OF THE
1031 MB HIGH JUST NW OF THE MADEIRA ISLANDS.

$$
WILLIS






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