Prognostic Meteorological Discussion
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
230 PM EDT MON MAY 02 2016

TROPICAL DISCUSSION FROM MAY 02/12UTC: BROAD MID/UPPER LEVEL RIDGE
EXTENDS ACROSS MEXICO-CENTRAL AMERICA TO THE CENTRAL CARIBBEAN.
THE RIDGE REMAINS ANCHORED ON A CLOSED HIGH TO THE SOUTH-SOUTHWEST
OF GUERRERO IN CENTRAL MEXICO. THE STRONG RIDGE PATTERN WILL HOLD
THROUGH TUESDAY EVENING...THEN RAPIDLY CRUMBLE ON WEDNESDAY AS A
HIGH AMPLITUDE/LONG WAVE TROUGH DEEPENS ACROSS THE USA TO THE
GULF. MEANWHILE...THE UPPER LEVEL RIDGE IS TO SUSTAIN AN UPPER
CONVERGENT PATTERN THAT IS TO INHIBIT ORGANIZED CONVECTION ACROSS
MOST OF MEXICO. DIURNAL CONVECTION...HOWEVER...IS TO BUILD ALONG
THE CONTINENTAL DIVIDE BETWEEN SOUTHERN GUATEMALA TO WESTERN
NICARAGUA. IN THIS AREA EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY
AND MAXIMA OF 20-35MM. THROUGH WEDNESDAY THIS DECREASES TO
05-10MM/DAY AND MAXIMA OF 15-20MM.

THE POLAR TROUGH...AS IT MEANDERS OVER THE USA...IS TO SUSTAIN A
SURFACE FRONT ACROSS TEXAS TO COAHUILA EARLY IN THE CYCLE. THROUGH
THIS EVENING THE FRONT IS TO MEANDER SOUTH INTO TAMAULIPAS...WHERE
IT IS TO SUSTAIN AN ONSHORE FLOW OF 20-25KT. THIS PUSHES THE FRONT
SOUTH ACROSS THE WESTERN GULF TO VERACRUZ THROUGH TUESDAY
EVENING...WHERE IT IS TO MEANDER THROUGH WEDNESDAY MORNING. LATER
IN THE DAY...UNDER INFLUENCE OF A BUILDING POLAR RIDGE...THE FRONT
SURGES ACROSS THE FLORIDA PENINSULA TO THE NORTHWEST
BAHAMAS-FLORIDA KEYS TO THE NORTHERN YUCATAN/SOUTHERN STATES OF
MEXICO. THE POLAR RIDGE IS TO THEN FAVOR NORTHERLIES OF 20-25KT
ACROSS THE GULF INTO SOUTHERN MEXICO-NORTHERN CENTRAL
AMERICA/WESTERN CARIBBEAN. THIS DISPLACES THE FRONT FARTHER TO THE
EAST...AND THROUGH THURSDAY MORNING IT WILL PUSH ACROSS THE
CENTRAL BAHAMAS TO CENTRAL/WESTERN CUBA-THE YUCATAN/NORTHERN
GUATEMALA-CHIAPAS IN SOUTHERN MEXICO. A PREFRONTAL TROUGH IS TO
THEN FORM OVER THE NORTHWEST CARIBBEAN. AS IT MEANDERS ACROSS
NORTHEAST MEXICO THIS WILL FAVOR RAINFALL AMOUNTS OF
00-05MM...WHILE OVER VERACRUZ-SOUTHERN STATES OF MEXICO TO THE
YUCATAN IT IS TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15-30MM ON TUESDAY AND WEDNESDAY. ACROSS
BELIZE-GUATEMALA-NORTHERN HONDURAS THE FRONT/PREFRONTAL TROUGH
WILL ALSO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-30MM ON THURSDAY. MOST INTENSE IS EXPECTED AS THE FRONT SURGES
ACROSS THE BAHAMAS-CUBA ON WEDNESDAY TO THURSDAY...TO FAVOR
RAINFALL AMOUNT OF 10-15MM/DAY AND MAXIMA OF 20-45MM IN MODERATE
TO HEAVY CONVECTION. ALTHOUGH FORECAST INDICES DO NOT SHOW
POTENTIAL FOR SEVERE CONVECTION...THE FAST PROPAGATION WOULD
LIKELY RESULT IN SQUALLY WEATHER.

AN UPPER LEVEL TROUGH BOUNDS THE EASTERN FRINGES OF THE
AFOREMENTIONED RIDGE...WITH AXIS TO THE SOUTH-SOUTHWEST ACROSS
HISPANIOLA/PUERTO RICO TO COLOMBIA. THIS TROUGH IS FORECAST TO
SLOWLY LIFT TO THE EAST-NORTHEAST THROUGH WEDNESDAY EVENING AS THE
POLAR TROUGH DEEPENS ACROSS THE EASTERN USA. AT MID LEVELS IT
SUSTAINS A BROAD TROUGH ACROSS THE ISLAND CHAIN/ EASTERN CARIBBEAN
TO NORTHERN VENEZUELA-COLOMBIA. THIS IS TO ALSO WEAKEN THROUGH
WEDNESDAY EVENING. AT LOW LEVELS...BROAD RIDGE OVER THE CENTRAL
ATLANTIC IS TO ANCHOR AT 850 HPA ON A CLOSED HIGH TO THE EAST OF
BERMUDA. THE HIGH/RIDGE WILL SUSTAIN A MOIST SOUTHEASTERLY FLOW
ACROSS THE EASTERN CARIBBEAN...WITH MOISTURE TO CONVERGE ACROSS
HISPANIOLA-PUERTO RICO-VIRGIN ISLES/NORTHERN LEEWARD ISLANDS.
ACROSS HISPANIOLA THIS IS TO RESULT IN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM/DAY THROUGH TUESDAY...AND
05-10MM/DAY AND MAXIMA OF 15-20MM THEREAFTER. OVER PUERTO
RICO-VIRGIN ISLES EXPECTING RAINFALL AMOUNTS OF 15-20MM/DAY AND
MAXIMA OF 25-50MM. THROUGH WEDNESDAY THIS DECREASES TO 10-15MM/DAY
AND MAXIMA OF 20-35MM. OVER THE LEEWARD AND FRENCH ISLANDS
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM
THROUGH TUESDAY. ON WEDNESDAY...AS THE TROUGH PULLS ACROSS THE
ISLANDS...THE MAXIMA INCREASES TO 15-20MM.

BROAD MID LEVEL TROUGH OVER THE EASTERN CARIBBEAN IS DRAWING THE
ITCZ/EQUATORIAL TROUGH NORTH OF ITS CLIMATOLOGICAL POSITION...WITH
CONVERGENCE ZONE ENTERING THE CONTINENT OVER THE NORTHERN GUIANAS.
ACROSS NORTHERN GUIANAS-NORTHEAST VENEZUELA THIS IS TO RESULT IN
RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM. BUT AS THE
TROUGH ALOFT WEAKENS THIS WILL DECREASE TO 05-10MM/DAY AND MAXIMA
OF 15-20MM THROUGH WEDNESDAY. OVER CENTRAL VENEZUELA EXPECTING
RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM. THROUGH
WEDNESDAY THIS DECREASES TO 10-15MM/DAY AND MAXIMA OF 20-35MM.
OTHER CONVECTION IS TO CLUSTER ACROSS NORTHWEST VENEZUELA TO
SANTANDERES IN COLOMBIA...WHERE WE EXPECT RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM. ON THE ANDEAN REGION/WESTERN
PLAINS OF COLOMBIA EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-35MM/DAY...WHILE OVER AMAZONIA TO THE SOUTHEAST INTO
SOUTHERN VENEZUELA EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-30MM...INCREASING TO 15-20MM/DAY AND MAXIMA OF
25-50MM ON TUESDAY. BUT THROUGH WEDNESDAY THIS WILL DECREASE TO
10-15MM/DAY AND MAXIMA OF 20-35MM.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC.
INITIAL    24    36    48    60    72    84    96         TYPE
NONE

CARDOS...SMN (MEXICO)
CABANERIT...INAMEH (VENEZUELA)
DAVISON/GALVEZ...WPC (USA)
$$





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