[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 191734
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST SAT 19 MAR 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1645 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N10W 3N30W EQ50W. SCATTERED STRONG
CONVECTION OVER SW AFRICA FROM 5N-9N BETWEEN 4W-10W. WIDELY
SCATTERED MODERATE CONVECTION WITHIN 60 NM EITHER SIDE OF AXIS
FROM 23W-40W.

...DISCUSSION...

GULF OF MEXICO...
WEAK SURFACE RIDGE PREVAILS OVER THE E TWO-THIRDS OF THE GLFMEX
AND FLORIDA WITH A 1022 MB HIGH CENTERED OVER N FLORIDA.
GENERALLY COOL/DRY CONDITIONS PREVAIL COURTESY OF THE
CONTINENTAL AIRMASS WHICH OVERSPREAD THE AREA YESTERDAY. OVER
THE W GULF...SLY RETURN FLOW CONTINUES TO PRODUCE PATCHY AREAS
OF LOW CLOUDS AND ISOLATED SHOWERS OFF THE MX/TX COASTS. LOOKING
UPSTREAM...YET ANOTHER POTENT S STREAM SHORTWAVE DISTURBANCE
MOVING EWD OVER THE SW UNITED STATES AND N MEXICO WILL BE THE
NEXT WEATHER MAKER AS IT MOVES INTO THE AREA TONIGHT INTO SUN
MORNING. DYNAMICAL MODELS INDICATE INCREASING CLOUDINESS THROUGH
THE REMAINDER OF TODAY OVER THE W GULF WITH
SHOWERS/THUNDERSTORMS DEVELOPING OFF THE SE TEXAS COAST TONIGHT.
THE SHORTWAVE AND ASSOCIATED SHOWER/THUNDERSTORM ACTIVITY SHOULD
MOVE INTO THE CENTRAL GULF SUNDAY. THEREAFTER...THE PROGRESSION
OF THE PATTERN BECOMES A LITTLE LESS CERTAIN WITH SOME
DIFFERENCES IN THE NUMERICAL MODELS. NONETHELESS...UNSETTLED/WET
CONDITIONS MAY EXIST OVER THE E GULF AND FLORIDA MONDAY INTO
TUE.

CARIBBEAN...
PERSISTENT MID/UPPER LEVEL RIDGE REMAINS ANCHORED ACROSS THE
AREA EXTENDING EXTENDING E/W ALONG 12N.  THERE IS A LITTLE UPPER
LEVEL MOISTURE MOVING AROUND THE W PERIPHERY OF THE RIDGE OVER
CENTRAL AMERICA AND THE W CARIBBEAN.  HOWEVER...MOST OF THE AREA
CONTINUES TO BE DOMINATED BY STRONG SUBSIDENCE AND DRY/STABLE
CONDITIONS ALOFT.  DRY CONDITIONS ALSO PREVAIL IN THE LOWER
LEVELS LIMITING SHOWER ACTIVITY SAVE SOME ISOLATED ACTIVITY
ALONG A REMNANT STATIONARY FRONT FROM THE E TIP OF CUBA TO
CENTRAL AMERICA NEAR THE HONDURAS/NICARAGUA BORDER.  THE BULK OF
THIS ACTIVITY IS FOCUSED NEAR THE S EXTENT OF THE BOUNDARY OVER
CENTRAL AMERICA.  MOISTURE WILL REMAIN PRIMARILY LIMITED OVER
MOST OF THE AREA THROUGH THE WEEKEND MAINTAINING THE VERY DRY
PATTERN WHICH HAS PREVAILED FOR SEVERAL WEEKS.

ATLANTIC...
STRONG MID/UPPER LEVEL RIDGING OVER THE CARIBBEAN WATERS IS
PRODUCING MAINLY W/WSW FLOW OVER THE W ATLC WATERS...WITH A WEAK
TROF CLIPPING THE AREA E OF BERMUDA.  ATTENDANT COLD FRONT
EXTENDS SWD FROM A 998 MB SFC LOW N OF THE AREA NEAR 34N48W SW
ALONG 27N60W THEN DISSIPATING STATIONARY TO THE E TIP OF CUBA.
MOST OF THE UPPER LEVEL DYNAMICS/SUPPORT WITH THIS SYSTEM IS
FOCUSED N OF THE AREA BUT LOW LEVEL MOISTURE POOLING IS
PRODUCING A NARROW BAND OF SCATTERED SHOWERS EXTEND UP TO 120 NM
SE OF THE COLD FRONT AND WITHIN 30 NM EITHER SIDE OF THE
DISSIPATING STATIONARY FRONT. BEHIND THE FRONT...MAINLY CLEAR
SKIES PREVAIL TO THE SE UNITED STATES COAST WHERE A 1013 MB LOW
OFF THE SOUTH CAROLINA COAST IS PRODUCING SCATTERED SHOWERS N OF
30N W OF 70W. FURTHER E...AN ELONGATED E/W SFC RIDGE SPANS
ACROSS MUCH OF THE CNTRL/ERN ATLC FROM JUST N OF THE LEEWARD
ISLANDS TO THE CANARY ISLANDS. A TIGHT PRESSURE GRADIENT ALONG
THE N PERIPHERY OF THE RIDGE IS PRODUCING MODERATE TO STRONG WLY
WINDS N OF 25N BETWEEN 25W-60W. ALTHOUGH THERE IS EXTENSIVE HIGH
CLOUDINESS N OF 25N BETWEEN 10W-30W...THERE IS VIRTUALLY NO
LARGE-SCALE PRECIPITATION OVER THE E HALF OF THE SUBTROPICAL
ATLC. FURTHER S...MODERATE SUBSIDENCE IN THE UPPER LEVELS AND
DRY AIR IN THE LOWER LEVELS MOVING OFF W AFRICA IS LARGELY
SUPPRESSING CLOUDS AND PRECIPITATION OVER THE TROPICAL ATLC WITH
THE ITCZ ACTIVITY SUPPRESSED SWD TO A POSITION CLOSER TO THE
EQUATOR WHERE THERE IS MORE MOISTURE AND UPPER DIVERGENCE.

$$
RHOME




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