Prognostic Meteorological Discussion
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FXCA20 KWBC 271922
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
222 PM EST MON FEB 27 2017

TROPICAL DISCUSSION FROM FEB 27/12 UTC: AT 500 HPA...A HIGH OVER
THE YUCATAN CHANNEL ANCHORS A RIDGE THAT SPANS BETWEEN
SOUTHERN/CENTRAL MEXICO TO THE NORTHERN CARIBBEAN ISLES. RIDGE
PATTERN IS FORECAST TO HOLD THROUGH THE MEDIUM RANGE PERIOD. THIS
IS TO MEANWHILE FAVOR A STRONG CAP INVERSION THAT IS GOING TO
INHIBIT ORGANIZED DEEP CONVECTION. AT LOW LEVELS...AN 850 HPA HIGH
TO THE NORTH-NORTHWEST OF BERMUDA IS TO ANCHOR A RIDGE OVER THE
WESTERN ATLANTIC TO THE NORTHERN CARIBBEAN AND THE GULF OF MEXICO.
A POLAR FRONT EXITING THE EASTERN USA ON THURSDAY MORNING IS TO
PRESS AGAINST THIS AXIS...FORCING THE HIGH/RIDGE TO RELOCATE TO
THE CENTRAL ATLANTIC. MEANWHILE...THIS IS TO FAVOR A TIGHT
GRADIENT AND BRISK EASTERLY TRADES ACROSS THE LESSER
ANTILLES-CARIBBEAN BASIN TO CENTRAL AMERICA. OVER THE NORTHERN
CARIBBEAN ISLES THE 850 HPA WINDS ARE TO PEAK AT 20-25KT...WHILE
OVER THE SOUTHERN CARIBBEAN/OFF THE COAST OF SOUTH AMERICA THE
WINDS WILL PEAK AT 25-30KT. THE BRISK EASTERLY TRADES ACROSS THE
BASIN WILL FAVOR GENERATION OF STREAMERS ACROSS THE ISLAND CHAIN.
THESE ARE TO GENERALLY FAVOR LIGHT RAINFALL AMOUNTS WITH
ACCUMULATION OF 00-05MM/DAY AND WIDELY ISOLATED MAXIMA OF 10MM. ON
THE CARIBBEAN COASTAL PLAINS OF NICARAGUA...COSTA RICA AND BELIZE
THE EASTERLY TRADES ARE TO ALSO FAVOR RAINFALL AMOUNTS OF
00-05MM/DAY AND MAXIMA OF 10MM.

AS THE MID LEVEL RIDGE HOLDS OVER THE BASIN...IT IS TO STEER A
SHORT WAVE TROUGH ON THE SOUTHERN STREAM ACROSS NORTHERN BAJA
CALIFORNIA DURING THE MORNING HOURS ON TUESDAY. A PLUME OF DEEP
SUBTROPICAL MOISTURE IS TO ACCOMPANY THIS FEATURE AS IT ADVECTS
ACROSS THE EASTERN PACIFIC...TO ENHANCE MOISTURE CONVERGENCE
ACROSS NORTHERN BAJA CALIFORNIA. INFLOW OF SHORT WAVE ENERGY AND
SUBTROPICAL MOISTURE WILL THEN FAVOR SCATTERED CONVECTION WITH
ACCUMULATION OF 15-20MM/DAY AND MAXIMA OF 35-70MM.

THE MID LEVEL TROUGH IS TO THEN CONTINUE ACROSS THE CENTRAL USA
EARLY ON WEDNESDAY MORNING...AND DURING THE DAY ON THURSDAY IT
LIFTS ACROSS THE EASTERN USA. AT LOW LEVELS THIS WILL SUSTAIN A
SURFACE FRONT ALONG THE USA/MEXICO BORDER LATER ON TUESDAY...WITH
BOUNDARY MOVING SOUTH ACROSS THE RIO BRAVO TO NORTHEAST STATES OF
MEXICO EARLY ON THURSDAY MORNING. ON THURSDAY...THE FROM MOVES
SOUTH ACROSS THE FLORIDA PENINSULA-GULF OF MEXICO TO SOUTHERN
TAMAULIPAS IN NORTHEAST MEXICO. THE TIGHTENING PRESSURE GRADIENT
WILL RESULT IN BOUNDARY LAYER WINDS OF 20-25KT ACROSS THE
NORTHWEST GULF TO NORTHEAST MEXICO. THIS WILL ENHANCE
TOPOGRAPHICALLY INDUCED CONVECTION ACROSS TAMAULIPAS TO FAVOR
RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM. THIS WILL
SPREAD SOUTH ACROSS VERACRUZ TO CENTRAL MEXICO ON THURSDAY.

SOUTH OF THE SUBTROPICAL RIDGE...OVER NORTHERN SOUTH
AMERICA...ENVIRONMENTAL CONDITIONS WILL BE MORE FAVORABLE AND
CONDUCIVE TO CONVECTION TO DEVELOP. OVER SOUTHWEST COLOMBIA...TO
AFFECT THE CAUCA/CAUCA VALLEY...DIURNAL CONVECTION WILL RESULT IN
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-20MM. THROUGH
WEDNESDAY THIS WILL INCREASE TO 15-20MM/DAY AND MAXIMA OF 25-50MM
AS ENHANCED BY LONG FETCH LOW LEVEL WESTERLY FLOW. OVER THE EJE
CAFETERO TO THE NORTHWEST...MEANWHILE... EXPECTING RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-20MM. OVER AMAZONIA IN
SOUTHERN COLOMBIA AND VENEZUELA EXPECTING RAINFALL AMOUNTS OF
15-20MM/DAY AND MAXIMA OF 30-60MM. THROUGH THURSDAY THIS WILL
DECREASE 10-15MM/DAY AND MAXIMA OF 20-35MM. OVER THE
GUIANAS...ITCZ/NEAR EQUATORIAL TROUGH RELATED CONVERGENCE WILL
SUSTAIN RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
25-50MM...WITH LOCALLY HIGHER AMOUNTS IN ASSOCIATION WITH EASTERLY
WAVES (SEE BELOW).

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC:
INITIAL   24     36     48     60     72     84     96    TYPE
09W      11W    14W    17W    20W    22W    24W    26W    TW
50W      52W    54W    56W    58W    60W    63W    66W    EW
60W      63W    66W    68W    71W    74W    77W    80W    EW
67W      71W    74W    77W    80W    83W    85W    87W    EW
75W      78W    80W    81W    DISSIPATES

A TROPICAL WAVE IS INITIALIZED OVER WESTERN AFRICA ALONG 09W. THIS
IS TO CONFINE TO THE ITCZ DURING THE NEXT FEW DAYS.

AN EASTERLY WAVE ALONG 50W MOVES OVER FRENCH GUIANA LATER THIS
EVENING...TO TRIGGER RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
30-60MM. THIS WILL CONTINUE ACROSS SURINAME ON TUESDAY...WHERE IT
IS TO FAVOR RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM.
ON WEDNESDAY MORNING IT MOVES ACROSS GUYANA TO EASTERN
VENEZUELA-SOUTHERN WINDWARD ISLES. OVER EASTERN VENEZUELA-GUYANA
IT WILL SUSTAIN RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
25-50MM...WHILE OVER THE SOUTHERN WINDWARD ISLES AND TRINIDAD AND
TOBAGO IT WILL RESULT IN RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15MM.

A WEAK EASTERLY WAVE ALONG 60W MOVES TO THE EASTERN CARIBBEAN
LATER TODAY. MOST ACTIVE CONVECTION WITH THIS FEATURE IS EXPECTED
OVER EQUATORIAL SOUTH AMERICA...WHERE IN INTERACTION WITH THE NEAR
EQUATORIAL TROUGH IT WILL SUSTAIN RAINFALL AMOUNTS OF 15-20MM/DAY
AND MAXIMA OF 30-60MM. ACROSS NORTHERN VENEZUELA AND THE ABC ISLES
IT IS TO INITIALLY FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND
MAXIMA OF 10MM. ON TUESDAY THIS WILL INCREASE TO 05-10MM/DAY AND
MAXIMA OF 15MM. OVER NORTHWEST VENEZUELA/SANTANDERES COLOMBIA THIS
WILL THEN TRIGGER RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15MM ON WEDNESDAY. OVER SOUTHWEST COLOMBIA IT IS TO THEN TRIGGER
RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM AS IT
INTERACTS WITH THE PANAMANIAN LOW.

AN EASTERLY WAVE ALONG 67W AND SOUTH OF 20N MOVES TO HISPANIOLA
LATER TODAY...TO TRIGGER RAINFALL AMOUNTS OF 00-05MM/DAY AND
MAXIMA OF 10MM. OVER VENEZUELA AND COLOMBIA MOST ACTIVE CONVECTION
IS EXPECTED ACROSS AMAZONIA TO THE SOUTH TO TRIGGER RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 30-60MM. ACROSS JAMAICA IT IS
TO MEANWHILE FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF
10MM. ON WEDNESDAY IT IS TO PULL ACROSS WESTERN PANAMA-COSTA RICA
WHERE IT WILL TRIGGER RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-25MM...WHILE OVER EASTERN NICARAGUA EXPECTING MAXIMA OF
15-20MM ON WEDNESDAY TO THURSDAY MORNING.

A WANING EASTERLY WAVE ALONG 75W IS TO DISSIPATE AS IT MOVES
ACROSS PANAMA TO COSTA RICA ON TUESDAY. MEANWHILE...OVER WESTERN
COLOMBIA IT IS TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-25MM...WHILE OVER WESTERN PANAMA EXPECTING RAINFALL AMOUNTS
OF 05-10MM/DAY AND MAXIMA OF 15-25MM ON TUESDAY.

JIMENEZ...IMN (COSTA RICA)
SUBRATH-ALI...TTMS (TRINIDAD AND TOBAGO)
GALVEZ/DAVISON...WPC (USA)

$$





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