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Tropical Discussion
 
(Latest Discussion - Issued 1824Z Jul 15, 2019)
 
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
224 PM EDT MON JUL 15 2019

TROPICAL DISCUSSION FROM JUL 15/12 UTC: WEST OVER THE DOMAIN...AT
250 HPA...A TROUGH EXTENDS TO THE SOUTH-SOUTHWEST FROM THE CENTRAL
USA TO NORTHEAST MEXICO. THIS SPLITS THE SUBTROPICAL RIDGE IN TWO
CELLS...WITH ONE OVER THE WESTERN USA/NORTHWEST MEXICO AND THE
OTHER OVER THE EASTERN USA. OVER THE NEXT THREE DAYS THE TROUGH IS
FORECAST TO WEAKEN AS THE RIDGE TO THE WEST BUILDS INLAND ACROSS
CENTRAL MEXICO. MEANWHILE...THE TROUGH ALOFT WILL ENHANCE DIURNAL
CONVECTION OVER NORTHEAST MEXICO TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-20MM. BUILDING RIDGE TO THE WEST IS
TO THEN VENT LATE AFTERNOON CONVECTION ALONG THE SIERRA MADRE
OCCIDENTAL TO THE WEST...TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY
AND MAXIMA OF 15-20MM...INCREASING TO 10-15MM/DAY AND MAXIMA OF
20-35MM ON WEDNESDAY.

A TUTT TO THE SOUTH EXTENDS TO THE NORTH-NORTHEAST FROM THE
EASTERN PACFIC...ACROSS SOUTHERN MEXICO TO THE YUCATAN PENINSULA.
CELL OF THE SUBEQUATORIAL RIDGE TO THE EAST DISPLACES THIS TROUGH
TO THE NORTH-NORTHWEST INTO THE WESTERN GULF-CENTRAL STATES OF
MEXICO ON TUESDAY. AS IT LIFT ACROSS GUATEMALA TO THE
YUCATAN-SOUTHERN MEXICO THIS WILL ENHANCE CONVECTIVE DEVELOPMENT.
OVER THE YUCATAN MOST ACTIVE IS EXPECTED ON TUESDAY WHEN IT IS TO
SUSTAIN RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-30MM.
OVER BELIZE-GUATEMALA THIS WILL FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM. OVER CENTRAL-SOUTHWEST MEXICO
INITIALLY EXPECTING ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF
15-20MM. THROUGH WEDNESDAY THIS INCREASES TO 10-15MM/DAY AND
MAXIMA OF 20-30MM.

FARTHER EAST...AT 250 HPA...A HIGH OVER PUERTO RICO ANCHORS A
SHORT WAVE RIDGE OVER THE EASTERN CARIBBEAN...WHILE AT MID LEVELS
A BROAD CELL OF THE SUBTROPICAL RIDGE DOMINATES THE FLOW OVER THE
ATLANTIC-NORTHERN CARIBBEAN. THE LATTER CENTERS ON A CLOSED HIGH
EAST OF THE BAHAMAS. UNDER THE INFLUENCE OF THIS RIDGE...A STRONG
TRADE WINDS INVERSION PREVAILS ACROSS THE NORTHEAST CARIBBEAN
ISLES. THROUGH WEDNESDAY AFTERNOON THE MODELS FORECAST THE GRADUAL
EROSION OF UPPER LEVEL RIDGE PATTERN...WITH RETROGRESSING TUTT LOW
TO MOVE OVER THE NORTHEAST CARIBBEAN LATER DURING THE DAY. AT MID
LEVELS THE TUTT WILL SUSTAIN AN INVERTED TROUGH. THIS ENTERS THE
NORTHEAST CARIBBEAN ON WEDNESDAY EVENING. AS IT REVOLVES AROUND
THE SUBTROPICAL RIDGE TO THE NORTH...THIS WILL LEAD TO GRADUAL
EROSION OF TRADE WINDS INVERSION. THIS WILL ALLOW FOR DEEPER
INSTABILITY AND MOISTURE TO POOL ACROSS THE EASTERN CARIBBEAN
ISLES LATER IN THE WEEK. MEANWHILE...THE MID LEVEL INVERSION WILL
INHIBIT ORGANIZED CONVECTION ACROSS THE NORTHEAST CARIBBEAN DURING
THE NEXT 48-60 HRS...WITH ENVIRONMENTAL CONDITIONS GRADUALLY
BECOMING MORE FAVORABLE ON THURSDAY AS A TROPICAL WAVE ENTERS THE
BASIN LATER IN THE WEEK.

TROPICAL/EASTERLY WAVES/TRADE WIND SURGES FROM 00 UTC:
INITIAL 24    36    48    60    72    84    96     TYPE    SOF
33W    38W   43W   48W   52W   56W   60W   63W       TW    18N
45W    48W   52W   56W   60W   64W   68W   72W       TI    27N
64W    69W   74W   79W   83W   86W   89W   92W       TW    16N
85W    88W   91W   94W   97W   99W  101W  103W       TW    17N
97W   100W  104W  108W  112W  116W  120W  124W       TW    14N

TROPICAL WAVE ALONG 33W REACHES THE GUIANAS ON WEDNESDAY
MORNING...TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-25MM...WITH SIMILAR AMOUNTS OVER THE ISLAND CHAIN ON THURSDAY.

A TUTT INDUCED PERTURBATION IN THE EASTERLY TRADES EXTENDS ALONG
45W. THIS ENTERS THE ISLAND CHAIN ON WEDNESDAY MORNING. OVER THE
LEEWARD/VIRGIN ISLES EXPECTING RAINFALL AMOUNTS OF 00-05MM/DAY AND
MAXIMA OF 10MM. ACROSS PUERTO RICO THIS IS TO TRIGGER SIMILAR
RAINFALL AMOUNTS.

A VIGOROUS TROPICAL WAVE IS INITIALIZED ALONG 64W. THIS IS
ACCOMPANIED BY A TRADE WINDS SURGE...WITH 850 HPA WINDS OVER THE
SOUTHERN CARIBBEAN PEAKING AT 35-40KT. THIS SUSTAINS THE NORTHWARD
MODULATION OF THE ITCZ ACROSS TRINIDAD/GRENADINES...TO THE ABC
ISLANDS...WHERE IT IS TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY
AND MAXIMA OF 15-25MM. ACROSS NORTHWEST VENEZUELA/ NORTHERN
COLOMBIA THIS IS TO THEN TRIGGER RAINFALL AMOUNTS OF 10-15MM/DAY
AND MAXIMA OF 20-45MM...WHILE OVER EASTERN AND SOUTHERN COLOMBIA
EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-35MM.
OVER JAMAICA EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-25MM EARLY IN THE CYCLE. OVER WESTERN COLOMBIA/THE DARIEN IN
EASTERN PANAMA THIS WILL SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY
AND MAXIMA OF 15-25MM. OVER WESTERN PANAMA-COSTA RICA/NICARAGUA
THIS WILL THEN SUSTAIN RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA
OF 20-30MM.

A TROPICAL WAVE ALONG 85W WILL SUSTAIN ISOLATED CONVECTION ACROSS
EL SALVADOR/HONDURAS EARLY IN THE CYCLE...WITH ACCUMULATION OF
10-15MM/DAY AND MAXIMA OF 20-35MM. OVER GUATEMALA-SOUTHERN MEXICO
THIS WILL THEN SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-25MM. ON WEDNESDAY THIS INCREASES TO 10-15MM/DAY AND MAXIMA
OF 20-30MM

TROPICAL WAVE ALONG 97W WILL TRIGGER SCATTERED CONVECTION ACROSS
SOUTHEAST MEXICO...WITH ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF
20-35MM.

JIMENEZ...FAC (COLOMBIA)
PAREDES...SENAMHI (PERU)
USECHE...IDEAM (COLOMBIA)
DAVISON...WPC (USA)