Prognostic Meteorological Discussion
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FXCA20 KWBC 281822
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
221 PM EDT MON JUL 28 2014

DISCUSSION FROM JULY 28/00UTC: MID/UPPER LEVEL RIDGE OVER THE
WESTERN USA/NORTHERN MEXICO IS FORECAST TO PERSIST OVER THE NEXT
FEW DAYS...TO ANCHOR AT 250 HPA ON A CLOSED HIGH OVER NEW MEXICO.
RIDGE AXIS IS TO ALSO EXTEND EAST ACROSS THE NORTHERN GULF OF
MEXICO-FLORIDA PENINSULA TO THE BAHAMAS. THE RIDGE TO THE
NORTH...AS IT HOLDS...IS TO STEER A TUTT LOW ACROSS CENTRAL MEXICO
TO THE EASTERN PACIFIC EARLY ON TUESDAY MORNING. THE TUTT LOW IS
TO THEN LIFT ACROSS THE BAJA PENINSULA THROUGH WEDNESDAY EVENING.
AS IT PULLS ACROSS CENTRAL MEXICO EARLY THIS CYCLE THIS IS TO
ENHANCE CONVECTIVE DEVELOPMENT ON THE STATES OF
GUERRERO-OAXACA-PUEBLA-MEXICO/DF-COLIMA-NAYARIT AND SINALOA. IN
THIS AREA EXPECTING RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
35-70MM. AS THE LOW/TROUGH PULLS AWAY THIS IS TO DECREASE TO
15-20MM/DAY AND MAXIMA OF 25-50MM. ACROSS BAJA PENINSULA SUR IT IS
TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-30MM
LATER ON TUESDAY TO EARLY WEDNESDAY...WHILE ACROSS SINALOA-SONORA
IT IS TO FAVOR RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
35-70MM ON TUESDAY TO WEDNESDAY EVENING.

POLAR TROUGH IS TO AMPLIFY ACROSS THE EASTERN USA TO THE WESTERN
ATLANTIC EARLY IN THE CYCLE. THIS AXIS IS TO REACH MAXIMUM
AMPLITUDE LATER ON TUESDAY...AND THROUGH THE DAY ON WEDNESDAY IT
STARTS TO LIFT. AT LOW LEVELS IT IS TO SUSTAIN A DEEP TROUGH ALONG
THE EASTERN SEABOARD OF THE USA LATER THIS EVENING INTO
TUESDAY...WITH ASSOCIATED FRONT TO REACH THE NORTHERN GULF OF
MEXICO ON TUESDAY MORNING. ACROSS THE BAHAMAS THIS IS TO SUSTAIN A
PREFRONTAL TROUGH...FORECAST TO ENHANCE MOISTURE CONVERGENCE
ACROSS THE NORTHWEST BAHAMAS...TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-25MM.

ANOTHER TUTT LOW LIES TO THE EAST...ORIGINATING ON A LOW NORTH OF
THE LEEWARD ISLES...WITH AXIS SOUTH TO THE NORTHEAST CARIBBEAN
ISLES AND WEST ACROSS HISPANIOLA/EASTERN CUBA TO THE NORTHWEST
CARIBBEAN. UNDER INFLUENCE OF THE RIDGE TO THE WEST...THE TUTT IS
TO STRETCH FARTHER WEST INTO THE WESTERN CARIBBEAN/NORTHERN
CENTRAL AMERICA LATER ON TUESDAY...WITH CLOSED LOW TO FORM NEAR
THE CAYMAN ISLES LATER IN THE DAY. THE TUTT ALOFT IS TO ENHANCE
SEA BREEZE RELATED CONVECTION ACROSS JAMAICA-HISPANIOLA AND PUERTO
RICO. ACROSS JAMAICA EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15MM...WITH MOST ACTIVE TODAY AND TUESDAY. ACROSS
HISPANIOLA MOST ACTIVE IS EXPECTED ACROSS CENTRAL PORTIONS OF THE
ISLAND...WITH ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15MM. OVER
PUERTO RICO EXPECTING SIMILAR AMOUNTS...WITH MOST ACTIVE ON THE
CORDILLERA CENTRAL AND WESTERN INTERIOR PORTIONS OF THE ISLAND.
THE TROUGH ALOFT SUSTAINS AN INDUCED PERTURBATION IN THE EASTERLY
TRADES...PLEASE SEE BELOW FOR DETAILS/FORECAST.

A WEAK CELL OF THE SUBTROPICAL RIDGE LIES TO THE SOUTH...EXTENDING
FROM SOUTHERN STATES OF MEXICO TO CENTRAL AMERICA/WESTERN
CARIBBEAN. THROUGH TUESDAY EVENING MODELS FORECAST THIS RIDGE TO
WEAKEN/COLLAPSE. MEANWHILE... ACROSS CENTRAL AMERICA-SOUTHERN
MEXICO...THIS IS TO PROVIDE THE VENTILATION ALOFT TO DEEP
CONVECTION. EARLY IN THE CYCLE EXPECTING ACCUMULATION OF
15-20MM/DAY AND MAXIMA OF 25-50MM ACROSS GUATEMALA-HONDURAS-EL
SALVADOR AND PORTIONS OF NICARAGUA. THROUGH WEDNESDAY EVENING THIS
DECREASES TO 05-10MM/DAY AND MAXIMA OF 15MM. OVER SOUTHERN
NICARAGUA-COSTA RICA AND PANAMA...MEANWHILE...EXPECTING
ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF 20-30MM.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL  24     36     48     60     72     84     96     TYPE
36W     38W    40W    43W    46W    50W    54W    56W     TW
55W     57W    60W    63W    65W    66W    67W    69W     TUTT
INDUCED
87W     89W    91W    93W    96W    99W   103W   106W     TW

A TROPICAL WAVE ALONG 36W SUSTAINS AN AREA OF ORGANIZED CONVECTION
ALONG THE ATLANTIC ITCZ. THE NHC IS MONITORING THIS SYSTEM FOR
POSSIBLE TROPICAL CYCLONE FORMATION DURING THE NEXT TWO DAYS.
MEANWHILE...MOST ACTIVE CONVECTION WITH THIS FEATURE IS EXPECTED
ALONG THE ITCZ.

A TUTT INDUCED PERTURBATION ON THE EASTERLY TRADES EXTENDS ALONG
55W. THIS IS TO ENTER THE LESSER ANTILLES EARLY ON TUESDAY
MORNING...TO FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF
10MM. ACROSS THE VIRGIN ISLES IT IS TO THEN FAVOR RAINFALL AMOUNTS
OF 00-05MM/DAY AND MAXIMA OF 10MM DURING THE DAY ON
TUESDAY...WHILE OVER PUERTO RICO AND THE DOMINICAN REPUBLIC
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM ON
WEDNESDAY TO THURSDAY MORNING. OVER EASTERN-CENTRAL VENEZUELA...IN
INTERACTION WITH THE NEAR EQUATORIAL TROUGH...IT IS TO THEN FAVOR
RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-35MM.

TROPICAL WAVE ALONG 87W IS TO SUSTAIN ORGANIZED CONVECTION ACROSS
EL SALVADOR-HONDURAS-GUATEMALA...WITH RAINFALL AMOUNTS OF
15-20MM/DAY AND MAXIMA OF 25-50MM. ACROSS GUERRERO-OAXACA/SOUTHERN
VERACRUZ-CHIAPAS MEXICO IT IS TO TRIGGER RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-40MM. ON THE CENTRAL STATES OF
MEXICO...IN INTERACTION WITH A TUTT TO THE WEST IT IS TO TRIGGER
RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM.

FIGUEROA...MARN (EL SALVADOR)
VALVERDE...IMN (COSTA RICA)
DAVISON...WPC (USA)
$$




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