[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 181742
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT FRI MAR 18 2016

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN 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
1715 UTC.

...SPECIAL FEATURE...

A STATIONARY FRONT IS OVER THE N GULF STATES AND EXTENDS FROM S
GEORGIA ACROSS SE LOUISIANA INTO CENTRAL TEXAS. A WEAK LOW PRES
IS FORECAST TO DEVELOP ALONG THIS FRONT OVER NW GULF OF MEXICO
ON SAT AS A REINFORCING PUSH OF COLD AIR MOVES IN BEHIND IT. THE
LOW WILL MOVE NE OUT OF THE GULF WITH THE COLD FRONT EXTENDING
FROM THE FLORIDA BIG BEND TO 21N96W TO 19N95W BY SAT NIGHT...
THEN MOVE SE OF THE AREA BY SUN EVENING. STRONG HIGH PRESSURE
BEHIND THE FRONT WILL PRODUCE GALE FORCE WINDS AND BUILDING SEAS
IN THE FAR SW GULF SUN AND SUN EVENING. EXPECT AN INCREASE IN
SHOWER AND TSTM ACTIVITY AHEAD OF THE FRONT AND WITH THE FRONTAL
PASSAGE.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS ACROSS SW AFRICA INTO THE E TROPICAL
ATLANTIC NEAR 05N08W TO 02N14W WHERE THE ITCZ BEGINS AND
CONTINUES ALONG 01N20W TO 02N30W THEN S OF THE EQUATOR NEAR
01S40W TO 01S46W. SCATTERED MODERATE ISOLATED STRONG CONVECTION
IS NOTED FROM THE EQUATOR TO 03N BETWEEN THE PRIME MERIDIAN AND
07W...FROM 02N TO 04N BETWEEN 10N AND 12N...AND FROM 01N TO 03N
BETWEEN 12N AND 15N. SCATTERED MODERATE CONVECTION PREVAILS
WITHIN ABOUT 75 NM N OF ITCZ AXIS BETWEEN 24W-31W.

...DISCUSSION...

GULF OF MEXICO...

WEAK HIGH PRES OF 1016 MB CENTERED OVER CENTRAL FLORIDA EXTENDS
A RIDGE ACROSS THE GULF WATERS. A STATIONARY FRONT IS OVER THE N
GULF STATES GENERATING SOME SHOWER AND TSTM ACTIVITY AS NOTED ON
LIGHTNING DATA. PART OF THIS CONVECTIVE ACTIVITY IS AFFECTING
THE NORTHERN GULF WATERS. A SURFACE TROUGH IS OVER THE SW GULF
EXTENDING FROM 24N94W TO 19N95W. THIS TROUGH WILL MOVE WESTWARD
AND DISSIPATE LATER TODAY BEFORE REDEVELOPING NEAR AND TO THE
WEST OF THE YUCATAN PENINSULA TONIGHT. MAINLY GENTLE TO MODERATE
SOUTHERLY WINDS ARE NOTED ACROSS THE REGION. UNDER THIS WARM AND
HUMID LOW LEVEL FLOW...PATCHES/AREAS OF FOG HAVE DEVELOPED OVER
THE NW WATERS THIS MORNING. A COLD FRONT IS FORECAST TO MOVE
ACROSS THE GULF DURING THE UPCOMING WEEKEND. PLEASE SEE SPECIAL
FEATURE FOR DETAILS. ALOFT...A SW-W WIND FLOW DOMINATES THE
MAJORITY OF THE AREA AHEAD OF AN UPPER LEVEL TROUGH CURRENTLY
LOCATED OVER THE SW CONUS AND NW MEXICO. THESE WINDS ARE
ADVECTING ABUNDANT MID/UPPER LEVEL MOISTURE ACROSS CENTRAL
MEXICO AND THE GULF INTO FLORIDA AND THE WESTERN ATLC.

CARIBBEAN SEA...

WEAK HIGH PRES OVER THE W-CENTRAL ATLC EXTENDS A RIDE TOWARD THE
NE CARIBBEAN. THE PRES GRADIENT BETWEEN THIS RIDGE AND THE
COLOMBIAN/PANAMANIAM LOW IS PRODUCING FRESH TO LOCALLY STRONG
TRADE WINDS ALONG THE COASTS OF COLOMBIA AND VENEZUELA...
MODERATE TO LOCALLY FRESH TRADES ACROSS THE EASTERN CARIBBEAN
AND MAINLY GENTLE TO MODERATE SE WINDS ACROSS THE WESTERN PART
OF THE BASIN. PATCHES OF LOW LEVEL MOISTURE EMBEDDED IN THE
TRADE WIND FLOW ARE SEEN ACROSS THE REGION MORE CONCENTRATED IN
THE LEE OF CUBA. THIS SHALLOW MOISTURE IS PRODUCING ISOLATED TO
SCATTERED PASSING SHOWERS. A COLD FRONT WILL MOVE ACROSS THE
GULF OF MEXICO REACHING THE YUCATAN CHANNEL AND WESTERN CUBA
LATE SUN. EXPECT AN INCREASE IN SHOWER AND TSTM ACTIVITY AHEAD
OF THE FRONT AND WITH THE FRONTAL PASSAGE. THEN...THE FRONT WILL
EXTEND FROM CENTRAL CUBA TO GULF OF HONDURAS LATE MON...AND
DISSIPATE FROM HAITI TO FAR E HONDURAS LATE TUE. IN THE UPPER
LEVELS...A RIDGE DOMINATES THE ENTIRE BASIN. STRONG SUBSIDENCE
ACCOMPANIES THE ANTICYCLONE AS EVIDENT IN RECENT WATER VAPOR
IMAGERY.

HISPANIOLA...

UNDER A SUBSIDENCE PATTERN ALOFT AND IMPLIED DRY AIR MASS...
EXPECT ONLY ISOLATED SHOWERS OVER THE NEXT 24-48 HOURS.

ATLANTIC OCEAN...

A WEAK 1019 MB HIGH PRES LOCATED NEAR 28N60W EXTENDS A RIDGE
ACROSS THE WESTERN ATLC. TO THE E...A COLD FRONT ENTERS THE
FORECAST REGION NEAR 31N45W THE CONTINUES SW TO 26N50W TO
22N60W. ISOLATED SHOWERS ARE ASSOCIATED WITH THE FRONTAL
BOUNDARY. THE FRONT WILL CONTINUE MOVING E WHILE WEAKENING.
MODERATE TO FRESH S-SW WINDS ARE N OF 28N AHEAD OF THE FRONT TO
41W PER THE MOST RECENT SCATTEROMETER DATA. ANOTHER RIDGE
ANCHORED BY A 1027 MB HIGH LOCATED NEAR 36N30W CONTROLS THE
WEATHER PATTERN ACROSS THE REMAINDER OF THE ATLC. A WEAK TROUGH
IS ANALYZED FROM 21N51W TO 14N52W. SOME INVERTED-V PATTERN IS
NOTED IN THE CLOUD FIELD ON VISIBLE SATELLITE IMAGERY IN
ASSOCIATION WITH THIS TROUGH. MOISTURE RELATED TO THIS TROUGH
MAY REACH THE LEEWARD ISLANDS BY SUN. A RIDGE/TROUGH/RIDGE
PATTERN DOMINATES THE AREA ALOFT.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
GR
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