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Tropical Discussion
 
(Caution: Version displayed is not the latest version. - Issued 1755Z Jul 07, 2020)
 
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
155 PM EDT TUE JUL 07 2020

TROPICAL DISCUSSION FROM JULY 07/16 UTC: AT 15 UTC...TROPICAL
STORM CRISTINA CENTERED AT 12.2N 102.8W. MINIMUM CENTRAL PRESSURE
WAS 1005 HPA AND MAXIMUM SUSTAINED WINDS 35KT WITH GUSTS TO 45KT.
CRISTINA WAS MOVING TO THE WEST-NORTHWEST OR 295 DEGREES AT 11KT.

NORTH IN THE DOMAIN AND AT UPPER LEVELS...A RIDGE AXIS EXTENDS
ACROSS THE NORTHERN BAJA CALIFORNIA PENINSULA INTO A CLOSED RIDGE
OVER TEXAS...WHILE A TUTT LOW CENTERS OVER THE NORTHERN YUCATAN
PENINSULA. MODELS ARE SUGGESTING THE TUTT RETROGRESSING WESTWARD
TO ARRIVE IN CENTRAL MEXIC BY THURSDAY EVENING. THE TUTT WILL
VENTILATE CONVECTION...BUT ACTIVITY WILL BE PRMARILY MODULATED BY
A TROPICAL WAVE DISSIPATING LATE ON TUESDAY...AND BY MOISTURE
TRANSPORT FROM THE SOUTHEAST INTO THE SOUTHERN SIERRA MADRE
OCCIDENTAL...IN ASSOCIATION WITH CRISTINA. ON TUESDAY...LARGEST
ACCUMULATIONS ARE EXPECTED IN CENTRAL MEXICO AND THE SIERRA MADRE
DEL SUR...WHERE POTIVE INTERACTION BETWEEN THE TROPICAL WAVE AND
AN UPPER TROUGH AXIS ASSOCIATED WITH THE TUTT IN THE YUCATAN
PENINSULA ARE EXPECTED TO FAVOR 15-20MM/DAY AND MAXIMA OF 35-70MM.
IN WESTERN MEXICO...FROM JALISCO INTO THE SIERRA MADRE OCCIDENTAL
OF SONORA AND CHIHUAHUA EXPECTING 10-15MM/DAY AND MAXIMA OF
20-40MM. IN THE SIERRA MADRE ORIENTAL...EXPECTING 05-10MM/DAY AND
MAXIMA OF 15-25MM. ON WEDNESDAY...LARGEST ACCUMULATIONS ARE
EXPECTED IN CENTRAL MEXICO AND ALONG THE SIERRA MADRE OCCIDENTAL
OF SINALOA AND SONORA...WHERE EXPECTING 15-20MM/DAY AND MAXIMA OF
25-50MM. IN SOUTHWEST MEXICO EXPECTING 05-10MM/DAY AND MAXIMA OF
15-25MM. A DRY AIR MASS ARRIVING FROM THE CARIBBEAN WILL SUSTAIN
MAXIMA UNDER 15MM/DAY IN AREAS TO THE EAST OF 98W AND ISOLATED
CONVECTION. ON THURSDAY...LARGEST AMOUNTS ARE EXPECTED BETWEEN
JALISCO/COLIMA AND SINALOA...WHERE DIURNAL CONVECTION WILL SUSTAIN
10-15MM/DAY AND MAXIMA OF 20-40MM. DIURNAL CONVECTION IN CENTRAL
MEXICO AND IN THE NORTHERN SIERRA MADRE OCCIDENTAL WILL FAVOR
05-10MM/DAY AND MAXIMA OF 15-25MM.

IN THE CARIBBEAN...TROPICAL WAVES ARE EXPECTED TO PLAY AN
IMPORTANT ROLE IN MODULATING CONVECTION AS THEY ARE CURRENTLY
TIGHTLY ASSOCIATED WITH THE VARIABILITY OF PRECIPITABLE WATER.
FROM THE WAVES PRESENT...THE MOST SIGNIFICANT IN TERMS OF
AVAILABLE MOISTURE IS CROSSING THE LESSER ANTILLES ON
TUESDAY...AND IS FORECAST TO CROSS HISPANIOLA IN WEDNESDAY...AND
ARRIVE INTO THE SOUTHEAST BAHAMAS/TURKS AND CAICOS...JAMAICA AND
SOUTHEAST CUBA ON THURSDAY. A SHARP DRY AIR MASS TRAILS THIS
WAVE...TO SUSTAIN A SHARP DECREASE IN PRECIPITATION IN THE
CARIBBEAN BASIN. AT UPPER LEVELS...A CELL OF THE SUBEQUATORIAL
RIDGE CENTERS OVER PUERTO RICO ON TUESDAY WHILE A TUTT EXTENDS
FROM THE SOUTHEAST BAHAMAS INTO SOUTHEAST CUBA. THE RIDGE IS
FORECAST TO RAPIDLY PROPAGATE WESTWARD TO CENTER OVER THE GULF OF
HONDURAS BY THURSDAY...WHILE THE TUTT WEAKENS WHILE MEANDER
SOUTHWARD TO EXTEND OVER HISPANIOLA BY LATE WEDNESDAY AND
THURSDAY. THE TUTT WILL INTERACT WITH THE TROPICAL WAVE TO SUSTAIN
MODERATE CONVECTION IN THE DOMINICAN REPUBLIC AND HAITI ON
WEDNESDAY. IN TERMS OF ACCUMULATIONS...LARGEST ACCUMULATIONS ON
TUESDAY ARE EXPECTED IN FROM THE CENTRAL LESSER ANTILLES INTO
PUERTO RICO IN ASSOCIATION THE THE ROBUST TROPICAL WAVE. EXPECTING
10-15MM/DAY AND MAXIMA OF 20-35M. WEST ACROSS HISPANIOLA EXPECTING
05-10MM/DAY AND MAXIMA OF 15-25MM...AS STIMULATED BY A WEAKER
TROPICAL WAVE. ISOLATED CONVECTION IN JAMAICA...CUBA...CAYMAN
ISLANDS AND THE NORTHWEST BAHAMAS WILL SUSTAIN 05-10MM/DAY AND
MAXIMA OF 15-20MM. ON WEDNESDAY...POSITIVE INTERACTION IN
HISPANIOLA WILL SUSTAIN 15-20MM/DAY AND SCATTERED MAXIMA OF
25-50MM. TO THE WEST...CONVECTION ASSOCIATED WITH THE MOIST PLUME
WILL FAVOR 05-10MM/DAY AND SCATTERED MAXIMA OF 15-25MM IN
JAMAICA...SOUTHEAST CUBA AND THE SOUTHEAST BAHAMAS/TURKS AND
CAICOS. ISOLATED CONVECTION IN WESTERN CUBA WILL FAVOR MAXIMA OF
15-25MM...WHILE IN PUERTO RICO EXPECTING ISOLATED MAXIMA OF 15M.
ON THURSDAY...LARGEST ACCUMULATIONS ARE EXPECTED IN THE SOUTHEAST
BAHAMAS...WHERE INTERACTIONS BETWEEN THE TROPICAL WAVE AND
ENHANCED VENTILATION IN THE SOUTHEASTERN PERIPHERY OF AN UPPER
RIDGE LOCATED TO THE NORTH...WILL FAVOR 10-15MM/DAY AND MAXIMA OF
20-35MM. IN CUBA EXPECTING 05-10MM/DAY AND MAXIMA OF
15-25MM...WHILE IN JAMAICA AND THE CAYMAN ISLANDS EXPECTING MAXIMA
OF 15MM.

DRY START IN MOST OF CENTRAL AMERICA WILL GIVE IN TO AN INCREASE
IN PRECIPITATION AS PERTURBATIONS IN THE TRADES SUSTAIN A GRADUAL
INCREASE IN PRECIPITABLE WATER. IN THE UPPER
TROPOSPHERE...VENTILATION WILL GRADUALLY INCREASE IN ASSOCIATION
WITH BUILDING CELL OF THE SUBEQUATORIAL RIDGE FROM TUSDAY THROUGH
THURSDAY. FURTHERMORE...PANAMANIAN LOW WILL BE QUITE ACTIVE AND
STIMULATED BY TROPICAL WAVES...TO SUSTAIN MODERATE PRECIPITATION
IN PANAMA THROUGH THE CYCLE. ON TUESDAY...LARGEST AMOUNTS ARE
EXPECTED FROM NORTHWEST COLOMBIA INTO MOST OF PANAMA...WHERE
EXPECTING 15-20MM/DAY AND MAXIMA OF 35-70MM. TO THE
WEST...ISOLATED CONVECTION IS EXPECTED IN MOST OF CENTRAL
AMERICA...TO SUSTAIN ISOLATED MAXIMA UNDER 15MM/DAY. LARGER
AMOUNTS ARE EXPECTED IN SOUTHERN BELIZE IN ASSOCIATION WITH
ENHANCED TRADE WIND CONVERGENCE/OROGRAPHIC FORCING WHERE EXPECTING
MAXIMA OF 15-25MM. ON WEDNESDAY...TROPICAL WAVE ENTERS PANAMA TO
REINFORCE THE PANAMANIAN LOW CIRCULATION. THIS WILL SUSTAIN
15-20MM/DAY AND MAXIMA OF 30-60MM FROM CENTRAL PANAMA INTO
SOUTHERN COSTA RICA...AND POTENTIALLY ISOLATED LARGER AMOUNTS IN
THE BOCAS DEL TORO REGION. IN NORTHERN COSTA RICA AND EASTERN
NICARAGUA EXPECTING AN INCREASE INTO 10-15MM/DAY AND MAXIMA OF
15-30MM/ SIMILAR AMOUNTS ARE EXPECTED IN EASTERN PANAMA AND
NORTHWEST COLOMBIA. IN NORTHERN CENTRAL AMERICA WEST INTO SOUTHERN
MEXICO...EXPECTING ISOLATED CONVECTION TO SUSTAIN 05-10MM/DAY AND
MAXIMA OF 15MM. ON THURSDAY...LARGEST ACCUMULATIONS ARE EXPECTED
IN COSTA RICA AND IN EASTERN NICARAGUA/EASTERN HONDURAS...WHERE
MOIST PLUME ASSOCIATED WITH TROPICAL WAVE WILL FAVOR 15-20MM/DAY
AND MAXIMA OF 30-60MM. IN HONDURAS...EL SALVADOR AND
SOUTHERN/CENTRAL GUATEMALA EXPECTING 05-10MM/DAY AND MAXIMA OF
15-25MM. SIMILAR AMOUNTS ARE EXPECTED IN MOST OF PANAMA.

IN NORTHERN SOUTH AMERICA...TROPICAL WAVES AND THE NET WILL PLAY
AN IMPORTANT ROLE IN MODULATONG CONVECTION. AS A DRY AIR MASS
PROPAGATES ACROSS THE CARIBBEAN...EXPECTING A RELOCATION OF THE
AREAS OF HEAVIEST PRECIPITATION FORM EXTREME NORTHERN SOUTH
AMERICA EARLY IN THE CYCLE INTO SOUTH-CENTRAL VENEZUELA AND
CENTRAL COLOMBIA BY THURSDAY. SEE THE TROPICAL WAVE SECTION FOR
RAINFALL ACCUMULATIONS.

TROPICAL/EASTERLY WAVES INITIALIZED ON JULY 07 AT 12 UTC:
TYPE - 07/12 08/00 08/12 09/00 09/12 10/00 10/12 11/00 SOF
TW   -   31W   35W   39W   43W   47W   51W   55W   59W 11N
TW   -   60W   64W   69W   73W   77W   81W   85W   89W 21N
TW   -   67W   71W   75W   79W   82W   86W   90W   94W 22N
TI   -   79W   82W   86W   91W   95W   99W  102W  105W 20N
TW   -   96W   99W  102W  DISS   ---   ---   ---   --- 16N
TW   -  118W  EXITS  ---   ---   ---   ---   ---   --- 21N

A TROPICAL WAVE IS INITIALIZED AT 31W. THE WAVE WILL REMAIN IN THE
TROPICAL ATLANTIC THROUGH THURSDAY EVENING...WHEN IT WILL APPROACH
FRENCH GUIANA TO INITIALLY FAVOR MAXIMA OF 15MM.

A ROBUST TROPICAL WAVE IS INITIALIZED AT 60W. THIS IS THE MOST
SIGNIFICANT TROPICAL WAVE IN THE BASIN AND IS ASSOCIATED WITH AN
IMPORTANT MOIST PLUME. HOWEVER...DRY AIR MASS TRAILS BEHIND THE
WAVE AXIS...TO SUSTAIN A NOTICEABLE DRYING TREND AS IT PROPAGATES
ACROSS THE CARIBBEAN. ON TUESDAY...THE WAVE WILL STIMULATE
CONVECTION IN THE CENTRAL LESSER ANTILLES...LEEWARD AND VIRGIN
ISLANDS AND IN PUERTO RICO...WHERE EXPECTING 10-15MM/DAY AND
MAXIMA OF 20-35MM. SIMILAR AMOUNTS ARE EXPECTED IN SOUTHEAST
VENEZUELA AND IN RORAIMA. IN NORTHEAST VENEZUELA AND NORTHERN
GUYANA EXPECTING 05-10MM/DAY AND MAXIMA OF 15-20MM. ON
WEDNESDAY...THE WAVE IS EXPECTED TO INTERACT WITH A TUTT NEAR
HISPANIOLA TO SUSTAIN 15-20MM/DAY AND MAXIMA OF 25-50MM. SIMILAR
AMOUNTS ARE EXPECTED IN THE LAKE MARACAIBO REGION AND
NORTHERN/CENTRAL COLOMBIA. ON THURSDAY...THE WAVE WILL STIMULATE
CONVECTION IN COSTA RICA...EASTERN NICARAGUA AND WESTERN PANAMA
WHERE EXPECTING 15-20MM/DAY AND MAXIMA OF 30-60MM. IN THE CAYMAN
ISLANDS IT WILL FAVOR MAXIMA OF 15MM...IN CUBA 05-10MM/DAY AND
MAXIMA OF 15-25MM...WHILE IN THE SOUTHEAST BAHAMAS EXPECTING
10-15MM/DAY AND MAXIMA OF 20-35MM.

A MUCH WEAKER TROPICAL WAVE IS INITIALIZED AT 67W. ON
TUESDAY...THE WAVE WILL SUSTAIN 05-10MM/DAY AND MAXIMA OF 15-25MM
IN HISPANIOLA AND WESTERN PUERTO RICO. IN SOUTH AMERICA...LARGEST
ACCUMULATIONS ARE EXPECTED IN NORTHWEST VENEZUELA AND NORTHERN
COLOMBIA IN INTERACTION WITH THE NET...WHERE EXPECTING 10-15MM/DAY
AND MAXIMA OF 20-40MM. CONVERGENCE OF WESTERLY WINDS IN THE LOW
LEVELS WILL SUSTAIN MAXIMA OF 35-70MM IN NORTHWEST COLOMBIA/EJE
CAFETERO. ON WEDNESDAY...THE WAVE WILL ENHANCE CONVECTION IN
JAMAICA AND SOUTHEAST CUBA...WHERE IT WILL FAVOR 05-10MM/DAY AND
MAXIMA OF 15-25MM. IN THE SOUTHEAST BAHAMAS EXPECTING MAXIMA OF
10MM. THE WAVE WILL ENHANCE CONVECTION IN SOUTHERN CENTRAL
AMERICA. IN EASTERN PANAMA AND IN NORTHWEST COLOMBIA EXPECTING
05-10MM/DAY AND MAXIMA OF 15-30MM. IN WESTERN PANAMA...COSTA RICA
AND SOUTHEAST NICARAGUA EXPECTING 10-15MM/DAY AND MAXIMA OF
20-40MM. ON THURSDAY...THE WAVE WILL FAVOR MAXIMA OF 30-60MM IN
SOUTHWEST NICARAGUA...WHILE IN NORTHERN CENTRAL AMERICA IT FAVORS
05-10MM/DAY AND MAXIMA OF 15-25MM.

A PERTURBATION ORIGINALLY INDUCED BY A TUTT IS RAPIDLY PROPAGATING
ACROSS THE CENTRAL CARIBBEAN...AND IS INITIALIZED AT 79W AND TO
THE SOUTH OF 20N. ON TUESDAY...THE WAVE WILL ENHANCE CONVECTION
PRIMARILY IN CUBA...THE CAYMAN ISLANDS AND IN JAMAICA...WHERE
EXPECTING 05-10MM/DAY AND MAXIMA OF 15-20MM. ON PANAMA AND COSTA
RICA THE WAVE WILL FAVOR MAXIMA OF 15MM. ON WEDNESDAY...THE WAVE
WILL ENHANCE CONVECTION IN NORTHERN CENTRAL AMERICA. BUT GIVEN THE
LIMITED AMOUNTS OF AVAILABLE MOISTURE THIS WILL SUSTAIN
05-10MM/DAY AND MAXIMA GENERALLY UNDER 15MM/DAY.

A TROPICAL WAVE IS INITIALIZED AT 96W. ON TUESDAY...IT WILL
ENLANCE CONVECTION IN OAXACA/GUERRERO AND SOUTHERN PUEBLA TO
SUSTAIN 15-20MM/DAY AND MAXIMA OF 35-70MM...AS IT INTERACTS WITH A
TUTT TO THE NORTH. HOWEVER...THE WAVE WILL THEN DISSIPATE AS IT
INTERACTS WITH THE WIND FIELD IN THE EASTERN PERIPHERY OF TROPICAL
STORM CRISTINA.

A TROPICAL WAVE IS INITIALIZED AT 118W AND IS MOVING WESTWARD INTO
THE OPEN WATERS OF THE CENTRAL PACIFIC...WITHOUT IMPACTS IN
COASTAL AREAS.

GALVEZ/DAVISON...WPC (USA)