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Tropical Discussion
 
(Caution: Version displayed is not the latest version. - Issued 1818Z Jul 29, 2022)
 
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
218 PM EDT FRI JUL 29 2022

FORECAST BULLETIN FROM 29 JULY 2022 AT 18 UTC: A CORRIDOR OF
RETROGRADING TUTTS CONTINUES ESTABLISHED ALONG 20-25N FROM THE
GULF OF MEXICO INTO THE PACIFIC. THESE WILL CONTINUE TO VENTILATE
DIURNAL CONVECTION IN MEXICO...IN COMBINATION WITH AN EASTERLY
WAVES. ON FRIDAY...EXPECT THE LARGEST ACCUMULATIONS FROM THE EJE
VOLCANICO TRANSVERSAL CENTRAL INTO NAYARIT/JALISCO AND SINALOA
WHERE AMOUNTS ARE FORECAST TO REACH 15-20MM/DAY AND ISOLATED
MAXIMA OF 25-50MM. IN THE SIERRA MADRE DEL SUR EXPECT 10-15MM/DAY
AND MAXIMA OF 20-35MM...WHILE IN THE HIGHLANDS OF SONORA AND IN
DURANGO/CHIHUAHUA EXPECT 05-10MM/DAY AND MAXIMA OF 15-20MM. ON
SATURDAY...AN EASTERLY WAVE WILL INTERACT WITH INSTABILITY BETWEEN
JALISCO AND NORTHERN SINALOA TO TRIGGER 15-20MM/DAY AND MAXIMA OF
30-60MM WITH A RISK FOR MCS FORMATION. IN SONORA EXPECT
05-10MM/DAY AND MAXIMA OF 15-30MM. ON SUNDAY...AS LARGE SCALE
UPPER CONVERGENCE INCREASES...EXPECT A GENERAL DECREASE IN
ACCUMULATIONS. THE EASTERLY WAVE WILL FAVOR 05-10MM/DAY AND MAXIMA
OF 15-25MM IN THE SIERRA MADRE OCCIDENTAL...WHILE IN SOUTHWEST
MEXICO/EJE VOLCANICO TRANSVERSAL EXPECT 10-15MM/DAY AND MAXIMA OF
20-35MM.

ALSO IN MEXICO...ACTIVE DEEP CONVECTION IS EXPECTED TO CONTINUE IN
THE YUCATAN PENINSULA UNDER THE INFLUENCE OF THE RECURRENT UPPER
TROUGH/TUTT PATTERN IN THE UPPER TROPOSPHERE AND TUTT-INDUCED
PERTURBATIONS. A DRIER AIR MASS MOVES IN FROM THE EAST ON SUNDAY
TO FAVOR A DECREASING TREND. ON FRIDAY EXPECT 10-15MM/DAY AND
MAXIMA OF 20-35MM...AND ON SATURDAY THIS DECREASES TO 05-10MM/DAY
AND MAXIMA OF 15-20MM.

AN EASTERLY WAVE WILL MODULATE ACCUMULATIONS IN CENTRAL AMERICA
TOGETHER WITH THE TUTT PATTERN LOCATED TO THE NORTH.
INITIALLY...TRADE WIND CONVERGENCE WILL FAVOR 10-15MM/DAY AND
MAXIMA OF 20-40MM IN SOUTHEAST NICARAGUA/NORTHERN COSTA RICA WHILE
ELSEWHERE EXPECT MORE ISOLATED CONVECTION TO PRODUCE ISOLATED
MAXIMA UNDER 15-25MM. ON SATURDAY...EXPECT A PEAK BETWEEN
NORTHEASST COSTA RICA AND EASTERN HONDURAS/MOST OF
NICARAGUA...WHERE AMOUNTS ARE FORECAST TO REACH 15-20MM/DAY AND
MAXIMA OF 30-60MM. IN SOUTHERN COSTA RICA AND SOUTHWEST PANAMA
EXPECT 10-15MM/DAY AND MAXIMA OF 20-35MM WITH THIS PERTURBATION.
ALSO ON SATURDAY...TUTT-ENHANCED CONVECTION IN GUATEMALA AND
BELIZE WILL FAVOR 10-15MM/DAY AND MAXIMA OF 20-35MM. ON
SUNDAY...EXPECT 10-15MM/DAY AND MAXIMA OF 20-35MM IN EASTERN
NICARAGUA/EASTERN HONDURAS. SIMILAR AMOUNTS ARE EXPECTED IN BELIZE
AND GUATEMALA WITH THE EASTERLY WAVE. IN CENTRAL HONDURAS AND IN
PANAMA AND COSTA RICA...EXPECT 05-10MM/DAY AND ISOLATED MAXIMA OF
15-20MM. NOTE A NOTICEABLE DECREASE IN EL SALVADOR AND NORTHWEST
NICARAGUA...IN ASSOCIATION WITH AN ACCELERATION OF THE EASTERLY
TRADES TRAILING THE PASSAGE OF THE EASTERLY WAVE.

WAVES ARE STARTING TO ACTIVATE AGAIN IN THE CARIBBEAN...ALTHOUGH
UNDER THE ENHANCED UPPER CONVERGENT PATTERN ASSOCIATED WITH THE
MJO...THEIR PROPAGATION IS EXPECTED TO BE FAST AND RAINFALL
AMOUNTS CONSERVATIVE. IN THE UPPER TROPOSPHERE...ZONAL EASTERLY
FLOW IS DEVELOPING WHILE A TUTT MOVES ACROSS CUBA ON FRIDAY INTO
THE GULF OF MEXICO LATER. THIS WILL LIMIT ENHANCEMENT BY UPPER
FEATURES...HIGHLITING THE ROLE OF LOW-LEVEL FEATURES IN MODULATING
THE VARIABILITY OF PRECIPITATION. ON FRIDAY...AN EASTERLY WAVE
ENTERS THE LEEWARD ISLANDS REACHING PUERTO RICO BY SATURDAY
MORNING. THIS WILL FAVOR 05-10MM/DAY AND MAXIMA OF 15-20MM. TO THE
WEST...TUTT CONVECTION WILL PEAK IN WESTERN CUBA TO FAVOR
10-15MM/DAY AND MAXIMA OF 20-40MM...WHILE IN EASTERN CUBA...CAYMAN
ISLANDS AND JAMAICA EXPECT 05-10MM/DAY AND MAXIMA OF 15-20MM. ON
SATURDAY...EXPECT 10-15MM/DAY AND MAXIMA OF 20-40MM IN HISPANIOLA
AS THE EASTERLY WAVE MOVES THROUGH. IN PUERTO RICO EXPECT MAXIMA
OF 15-25MM ASSOCIATED WITH THE TRAILING MOIST PLUME. ISOLATED
CONVECTION IN WESTERN JAMAICA AND WESTERN CUBA WILL FAVOR
05-10MM/DAY AND MAXIMA OF 15-20MM...WHILE A TROPICAL WAVE FAVORS
SCATTERED AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM IN THE
CENTRAL AND SOUTHERN LESSER ANTILLES. NOTE THAT HIGHER AMOUNTS ARE
POSSIBLE IN TRINIDAD. ON SUNDAY...THE EASTERLY WAVE WILL FAVOR
10-15MM/DAY AND MAXIMA OF 20-35MM IN CENTRAL CUBA...WHILE IN THE
NORTHWEST AND CENTRAL BAHAMAS EXPECT 05-10MM/DAY AND MAXIMA OF
15-20MM. IN HISPANIOLA EXPECT 05-10MM/DAY AND MAXIMA OF 15-25MM.
IN THE ABC ISLANDS...THE TROPICAL WAVE WILL FAVOR 05-10MM/DAY AND
ISOLATED MAXIMA OF 15-25MM...WHILE ITCZ CONVERGENCE AND LOW-LEVEL
JET DYNAMICS FAVOR 15-20MM/DAY AND ISOLATED MAXIMA OF 25-50MM IN
TRINIDAD AND EXTREME EASTERN VENEZUELA.

IN NORTHERN SOUTH AMERICA...THE UPPER TROPOSPHERIC PATTERN IS ALSO
EXPECTED TO REMAIN NEUTRAL FOR ANY ENHANCEMENT. ACTIVITY WILL
PRIMARILY CLUSTER ALONG THE NET AND TROUGHS/WAVES IN THE LOWER
TROPOSPHERE. ON FRIDAY...AN EASTERLY WAVE FAVOR 05-10MM/DAY AND
MAXIMA OF 15-30MM IN  CENTRAL AND SOUTHWEST COLOMBIA. IN SOUTHEAST
VENEZUELA INTO CENTRAL GUYANA AND SURINAME...TRADE WIND
CONVERGENCE AND THE NET WILL FAVOR 15-20MM/DAY AND MAXIMA OF
30-60MM. ELSEWHERE IN THE GUIANAS EXPECT SCATTERED CONVECTION WITH
AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-35MM. ON SATURDAY...EXPECT
15-20MM/DAY AND MAXIMA OF 25-50MM IN WESTERN GUYANA AND EASTERN
VENEZUELA/NORTHEAST RORAIMA...AS A TROPICAL WAVE MOVES IN. IN
SURINAME AND SOUTHERN GUYANA...AS WELL AS IN NORTHEAST AND
CENTRAL/SOUTHWEST VENEZUELA EXPECT 05-10MM/DAY AND MAXIMA OF
15-30MM. ENHANCED INSTABILITY AND LOW-LEVEL WESTERLIES IN COLOMBIA
WILL FAVOR 10-15MM/DAY AND MAXIMA OF 20-40MM IN CENTRAL AND
NORTHWEST PORTIONS. ON SUNDAY...EXPECT 15-20MM/DAY AND MAXIMA OF
25-50MM IN CENTRAL/WESTERN COLOMBIA AND THE SANTANDERES...AS WELL
AS IN EXTREME WESTERN VENEZUELA...AS A TROPICAL WAVE APPROACHES.
TROPICAL WAVE CONVECTION IN EASTERN CILIMBIA/SOUTHWEST VEN EZUELA
WILL FAVOR 05-10MM/DAY AND MAXIMA OF 15-30MM. MODERATE AMOUNTS ARE
ALSO EXPECTED IN NORTHEAST VENEZUELA/NORTHERN GUIYANA WHERE ITCZ
CONVECTION WILL BE ENHANCED BY THE SOUTHERN FRINGE3S OF A
LOW-LEVEL JET TO THE NORTH. THIS WILL FAVOR 15-20MM/DAY AND MAXIMA
OF 25-50MM.

TROPICAL WAVES/TUTT INDUCED PERTURBATIONS/TRADE WIND SURGES
INITIALIZED AT 12 UTC:
TYPE  INIT SOF 30/00 30/12 31/00 31/12 01/00 01/12 02/00 02/12
TW     47W 18N   50W   55W   60W   65W   70W   75W   80W   85W
EW     58W 28N   61W   65W   70W   75W   79W   84W   89W   93W
EW     71W 16N   73W   78W   83W   87W   92W   97W  102W  107W  
EW     97W 31N  101W  103W  105W  107W  109W  111W  113W  115W

A TROPICAL WAVE IS INITIALIZED AT 47W AND TO THE SOUTH OF 18N. ON
FRIDAY...THE WAVE WILL FAVOR A MAXIMA OF 20-35MM IN SURINAME AND
FRENCH GUIANA. ON SATURDAY...EXPECT 15-25MM IN EASTERN PUERTO RICO
AND WINDWARD ISLANDS...A MAXIMA OF 25-50MM IN CENTRAL AND
NORTHEASTERN VENEZUELA...A MAXIMA OF 20-35MM IN SOUTHERN
VENEZUELA...A MAJOR PART OF GUYANA...SURINAME AND FRENCH GUIANA.
EXPECT A MAXIMA OF 15-20MM IN NORTHERN BRAZIL. ON SUNDAY...THE
WAVE WILL FAVOR A MAXIMA OF 25-50MM IN NORTHERN COLOMBIA AND
WESTERN VENEZUELA. EXPECT A MAXIMA OF 15-20MM IN NORTHERN
ECUADOR..PORTION OF NORTHERN PERU...SOUTHERN AND EASTERN COLOMBIA
AND SOUTHERN VENEZUELA...COSTA RICA AND PANAMA.

AN EASTERLY WAVE IS INITIALIZED AT 58W AND TO THE SOUTH OF 28N.
EXPECT A MAXIMA OF 15-20MM IN EASTERN PUERTO RICO AND LESSER
ANTILLES. ON SATURDAY...THE WAVE WILL FAVOR A MAXIMA OF 20-40MM
DOMINICAN REPUBLIC AND A MAXIMA OF 15-20MM IN WESTERN JAMAICA. ON
SUNDAY...EXPECT A MAXIMA OF 20-35MM IN CENTRAL CUBA AND A MAXIMA
OF 15-20MM IN NORTHERN BAHAMAS.

AN EASTERLY WAVE IS INITIALIZED AT 71W AND TO THE SOUTH OF 16N. ON
FRIDAY...EXPECT A MAXIMA OF 20-35MM IN NORTHWESTERN COLOMBIA...A
MAXIMA OF 15-20MM IN COSTA RICA...PANAMA... AND MORE OF LESS THE
SAME AMOUNT IN WESTERN VENEZUELA...EASTERN COLOMBIA...PORTION OF
NORTHERN BRAZIL AND NORTHERN ECUADOR. ON SATURDAY...EXPECT A
MAXIMA OF 25-50MM IN EASTERN NICARAGUA AND EASTERN HONDURAS.
EXPECT A MAXIMA OF 20-40MM IN SOUTHERN NICARAGUA AND WESTERN
COASTAL AREAS OF COSTA RICA. ON SUNDAY...THE WAVE WILL FAVOR A
MAXIMA OF 20-35MM IN EASTERN MEXICO...GUATEMALA...BELIZE AND EL
SALVADOR.

AN EASTERLY WAVE IS INITIALIZED AT 97W AND TO THE SOUTH OF 31N.
THE WAVE WILL BE IN MEXICO AND WILL FAVOR A MAXIMA OF 20-35MM IN
ITS SOUTHERN PART...A MAXIMA OF 15-20MM IN ITS NORTHERN AND
EASTERN PART AND A MAXIMA OF 25-50MM IN ITS WESTERN PART. ON
SATURDAY...THE WAVE WILL FAVOR A MAXIMA OF 25-50MM IN WESTERN
MEXICO...A MAXIMA OF 20-35MM IN ITS NORTHWESTERN PART AND 15-20MM
IN ITS SOUTHERN PART. ON SUNDAY...THE WAVE WILL FAVOR A MAXIMA OF
15-25MM IN NORTHERN MEXICO AND A MAXIMA OF 20-40MM IN ITS CENTRAL
PART.

GALVEZ/DIAWARA...WPC (USA)