000
AXNT20 KNHC 170514
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST FRI MAR 17 2006

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...WEATHER OBSERVATIONS... 
RADAR...AND METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0345 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 6N10W 5N16W 3N30W 3N51W. SCATTERED 
MODERATE/STRONG CONVECTION IS S OF 2N ACROSS THE EQUATOR BETWEEN 
10W-13W...WITHIN 60 NM OF 3.5N FROM 7W-11W...AND FROM 2N-5N E OF 
2W ACROSS THE PRIME MERIDIAN. SCATTERED MODERATE/ISOLATED STRONG 
IS WITHIN 60 NM OF THE ITCZ AXIS E OF 13W TO INLAND OVER AFRICA 
AND WITHIN 120 NM N OF THE ITCZ AXIS FROM 23W-30W. CLUSTERS OF 
SIMILAR CONVECTION ARE FROM 2N-7N BETWEEN 41W-52W. 
 
...DISCUSSION...

GULF OF MEXICO...
DEEP LAYERED TROUGH IS APPROACHING THE NW GULF CURRENTLY OVER 
THE CENTRAL PLAIN STATES WITH ASSOCIATED COLD FRONT STILL INLAND 
OVER TEXAS. WEAK 1022 MB SURFACE HIGH IS OVER THE BIG BEND AREA 
OF FLORIDA WITH THE WEAK RIDGE COVERING MUCH OF THE GULF. A 
SURFACE TROUGH IS OVER THE FLORIDA PENINSULA FROM NAPLES TO 
JACKSONVILLE SEPARATING THE RIDGE FROM THE RIDGE IN THE W ATLC. 
THE GULF IS UNDER UPPER WESTERLY ZONAL FLOW IN RESPONSE TO AN 
UPPER RIDGE OVER THE W ATLC. WEAK COLD FRONT WILL ENTER THE GULF 
OVER THE NEXT 12 HOURS MOVING EXITING THE GULF LATE IN THE DAY 
ON SAT. A SECOND SURFACE RIDGE WILL MOVE S FROM OVER THE US INTO 
THE GULF SAT FOR THE REMAINDER OF THE WEEKEND. 

CARIBBEAN SEA...
UPPER SW FLOW DOMINATES THE W CARIBBEAN W OF 75W WITH UPPER 
WESTERLY ZONAL FLOW OVER THE EAST. STRONG SUBSIDENCE AND DRY 
UPPER AIR CONTINUES TO HAVE A FIRM HOLD OF THE ENTIRE AREA. 
ALTHOUGH TROPICAL MOISTURE IS BEING ADVECTED FROM OVER SOUTH 
AMERICA GENERATING SCATTERED SHOWERS ALONG THE COAST OF 
COLOMBIA. AFRICAN DUST HAS CONTINUED TO THIN DUE TO THE 
MODERATE/STRONG EASTERLY TRADE WINDS. LITTLE CHANGE IS EXPECTED 
FOR THE AREA DURING THE FIRST PART OF THE WEEKEND. 

ATLANTIC OCEAN...
BROAD UPPER RIDGE CONTROLS THE W ATLC WITH THE AXIS EXTENDING 
FROM CENTRAL CUBA NNE TO 31N71W. AT THE SURFACE...A 1023 MB HIGH 
IS LOCATED NEAR 29N72W COVERING THE W ATLC W OF THE CENTRAL ATLC 
FRONTAL BOUNDARY. DEEP LAYERED TROUGH IS IN THE CENTRAL ATLC N 
OF 19N FROM 45W-63W WITH THE ASSOCIATED COLD FRONT EXTENDING 
INTO THE AREA NEAR 32N50W TO 23N62W WHERE IT BECOMES STATIONARY 
TO THE TURKS AND CAICOS NEAR 22N72W. SCATTERED SHOWERS ARE 
WITHIN 60 NM E OF THE FRONT N OF 27N WITH ISOLATED SHOWERS 
WITHIN 45 NM E OF THE REMAINDER OF THE COLD FRONT. UPPER RIDGE 
COVERS THE E/CENTRAL ATLC EXTENDING FROM NEAR 19N43W N TO BEYOND 
32N39W. AT THE SURFACE...A 1021 MB HIGH IS LOCATED NEAR 25N46W 
WITH A RIDGE COVERING THE REMAINDER OF THE ATLC E OF THE FRONT. 
A VERY WELL DEFINED DEEP LAYERED LOW...AND THE ASSOCIATED GALE 
CENTER IS REMAINS N OF THE REGION WITH THE UPPER TROUGH 
EXTENDING THROUGH 32N20W TO 20N26W. ASSOCIATED SURFACE FEATURES 
ARE N OF THE REGION. THE DENSE AFRICAN DUST REMAINS OVER E ATLC 
N OF THE ITCZ AND S OF A LINE FROM THE AFRICAN COAST NEAR 24N16W 
TO 16N47W. BROAD UPPER RIDGE EXTENDS ACROSS THE TROPICAL ATLC 
FROM AFRICA NEAR 5N10W ALONG 7N40W TO OVER SOUTH AMERICA NEAR 
9N58W ENHANCING CONVECTION WITHIN THE ITCZ ESPECIALLY OFF THE 
AFRICAN COAST. OTHERWISE...GENERALLY TRANQUIL WEATHER PREVAILS 
OVER THE MOST OF THE ATLC. 

$$
WALLACE