Prognostic Meteorological Discussion
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FXCA20 KWBC 301525
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1124 AM EDT TUE SEP 30 2014

DISCUSSION FROM SEPTEMBER 30/00UTC: AT 250 HPA...THE SUBTROPICAL
RIDGE EXTENDS FROM CENTRAL MEXICO TO THE GULF/FLORIDA PENINSULA.
THE RIDGE IS TO HOLD NEARLY UNCHANGED DURING THE NEXT FEW DAYS.
MEANWHILE...THIS IS TO PROVIDE VENTILATION ALOFT TO DEEP
CONVECTION ACROSS MEXICO. THE MOST ACTIVE IS EXPECTED ACROSS THE
CENTRAL-SOUTHWEST STATES...WHERE A TROPICAL WAVE IS TO FAVOR
ORGANIZED DEEP CONVECTION OVER THE NEXT COUPLE OF DAYS. IN THIS
AREA EXPECTING RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
35-70MM. LESSER AMOUNTS ARE EXPECTED ALONG THE SIERRA MADRE
OCCIDENTAL...WITH DIURNAL CONVECTION TO SUSTAIN ACCUMULATION OF
05-10MM/DAY AND MAXIMA OF 15MM...WHILE ACROSS SINALOA TO
NAYARIT/COLIMA EXPECTING ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF
20-30MM. ON THE SOUTHERN STATES OF MEXICO-GUATEMALA-EL
SALVADOR/HONDURAS EXPECTING RAINFALL AMOUNTS OF 15-20MM/DAY AND
MAXIMA OF 25-50MM AS THE RIDGE ALOFT VENTS DEEP CONVECTION ALONG
THE CONTINENTAL DIVIDE. OVER BELIZE-NORTHERN GUATEMALA TO THE
YUCATAN... MEANWHILE... EXPECTING ACCUMULATION OF 05-10MM/DAY AND
MAXIMA OF 15-20MM.

RIDGE OVER MEXICO/GULF IS TO GRADUALLY EXPAND ACROSS THE
BAHAMAS/CUBA TO THE SOUTHWEST ATLANTIC...TO ENVELOP AREA NORTH OF
THE GREATER ANTILLES EARLY ON WEDNESDAY. EAST AND SOUTH OF THIS
RIDGE...A TUTT EXTENDS FROM THE NORTHEAST TO THE SOUTHERN
CARIBBEAN. AS THE RIDGE BUILDS TO THE NORTH...THE TUTT IS TO
BECOME NARROW AN ELONGATED. A TUTT LOW IS TO THEN FORM NORTH OF LA
GUAJIRA PENINSULA LATER ON WEDNESDAY...WHERE IT IS TO MEANDER
THROUGH THURSDAY EVENING/EARLY FRIDAY MORNING. AT 500 HPA...A HIGH
OVER THE NORTHERN LEEWARD ISLANDS EXTENDS A RIDGE ACROSS THE
EASTERN CARIBBEAN. THIS FAVORS A TRADE WINDS CAP AND LOW
PRECIPITABLE WATER CONTENT. MID LEVEL RIDGE PATTERN HOLDS ACROSS
THE EASTERN CARIBBEAN THROUGH TUESDAY EVENING...THEN LIFTS TO THE
WEST-NORTHWEST ACROSS HISPANIOLA TO EASTERN CUBA. AS IT PULLS
AWAY... TRADE WINDS CAP OVER THE EASTERN CARIBBEAN WILL START TO
WEAKEN...WHILE OVER CUBA-JAMAICA-CAYMAN ISLES-THE BAHAMAS IT IS TO
STRENGTHEN. THROUGH THURSDAY MORNING THE RIDGE LIFTS NORTH OF THE
GREATER ANTILLES...PHASING WITH UPPER LEVEL RIDGE OVER THE
SOUTHWEST ATLANTIC.

THE TUTT...AS IT MEANDERS ACROSS THE CENTRAL CARIBBEAN...IS TO
INTERACT WITH THE EASTERN PACIFIC ITCZ...TO ENHANCE CONVECTION
ACROSS SOUTHERN NICARAGUA-COSTA RICA TO PANAMA. IN THIS AREA
EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM.
IT IS TO ALSO ENHANCE DIURNAL CONVECTION ACROSS THE CAYMAN
ISLES...WHERE WE EXPECT RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA
OF 20-35MM THROUGH TUESDAY EVENING. OVER COLOMBIA-NORTHWEST
VENEZUELA... INITIALLY EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY
AND MAXIMA OF 15-25MM. THROUGH WEDNESDAY EVENING...AS THE TUTT LOW
FORMS TO THE NORTH OVER THE CARIBBEAN...THIS INCREASES TO
10-15MM/DAY AND MAXIMA OF 20-40MM.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL  24     36     48     60     72     84     96     TYPE
54W     57W    60W    64W    68W    71W    74W    77W     TW
87W     89W    91W    93W    94W    96W    97W    99W     TW
99W    101W   102W   103W   104W   105W   106W   108W     TW

TROPICAL WAVE ALONG 54W IS TO TRIGGER ISOLATED CONVECTION ACROSS
THE NORTHERN GUIANAS EARLY THIS CYCLE...WITH RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM. THE WAVE ENTERS THE LESSER
ANTILLES ON WEDNESDAY MORNING... WHERE IT IS TO ALSO FAVOR
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM IN ISOLATED TO
SCATTERED CONVECTION. OVER PUERTO RICO EXPECTING ACCUMULATION OF
00-05MM/DAY AND MAXIMA OF 10MM...WHILE OVER THE DOMINICAN REPUBLIC
IT INCREASES TO 05-10MM/DAY AND MAXIMA OF 15-20MM. THE MOST ACTIVE
IS EXPECTED TO THE SOUTH AS IT INTERACTS WITH THE NET OVER
VENEZUELA/COLOMBIA. ACROSS EASTERN-CENTRAL VENEZUELA IT IS TO
FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-25MM...WHILE ACROSS NORTHWEST VENEZUELA/SANTANDERES COLOMBIA
EXPECT ACCUMULATION OF 15-20MM/DAY AND MAXIMA OF 25-50MM.

THE TROPICAL WAVE ALONG 87W MOVES ACROSS EL
SALVADOR/HONDURAS-GUATEMALA EARLY IN THE CYCLE...WHERE IT IS TO
SUSTAIN RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM.
OVER NORTHERN GUATEMALA/BELIZE...MEANWHILE...IT IS TO FAVOR
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-20MM. ON THE
SOUTHERN-CENTRAL STATES OF MEXICO IT IS TO THEN FAVOR RAINFALL
AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM.

TROPICAL WAVE ALONG 99W SUSTAINS SCATTERED CONVECTION ACROSS THE
SOUTHWEST-CENTRAL STATES OF MEXICO...WITH ACCUMULATION OF
15-20MM/DAY AND MAXIMA OF 30-60MM. HIGHER AMOUNTS...HOWEVER...ARE
EXPECTED ALONG THE COAST BETWEEN GUERRERO-OAXACA...WHERE IN A
BRISK SOUTHEASTERLY FLOW EXPECTING MAXIMA OF 40-80MM...WITH MOST
INTENSE EXPECTED ON WEDNESDAY.

VALVERDE...IMN (COSTA RICA)
MEDINA...ONAMET (REPUBLICA DOMINICANA)
DAVISON...WPC (USA)
$$




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