Prognostic Meteorological Discussion
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TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
226 PM EDT TUE MAY 24 2016

TROPICAL DISCUSSION FROM MAY 24/12UTC: BROAD MID/UPPER LEVEL RIDGE
REMAINS WELL ENTRENCHED ACROSS WESTERN PORTIONS OF THE
DOMAIN...WITH AXIS EXTENDING ACROSS MEXICO-CENTRAL AMERICA TO THE
SOUTHERN USA WHILE ORIGINATING ON A 500 HPA HIGH OVER CENTRAL
MEXICO. BROAD RIDGE IS TO GENERALLY PERSIST OVER THE NEXT FEW
DAYS...WITH EROSION EXPECTED TO THE NORTH OF 25N LATER IN THE WEEK
AS DEEP TROUGH PULLS ACROSS THE WESTERN TO THE CENTRAL USA.
MEANWHILE...THE RIDGE ALOFT WILL FAVOR A CAP INVERSION THAT IS TO
GENERALLY FAVOR FAIR WEATHER CONDITIONS. DIURNAL
ACTIVITY...HOWEVER...IS FORECAST TO CONFINE TO THE SIERRA MADRE
ORIENTAL BETWEEN COAHUILA AND PUEBLA/VERACRUZ. IN THIS AREA
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM/DAY
THROUGH THIS AFTERNOON...WHILE ON WEDNESDAY AND THURSDAY THE
MAXIMA INCREASES TO 15-20MM.

DOWNSTREAM FROM THE CONTINENTAL RIDGE...A HIGH AMPLITUDE MID/UPPER
LEVEL TROUGH EXTENDS OVER THE WESTERN ATLANTIC-CUBA TO THE CENTRAL
CARIBBEAN. THE RIDGE TO THE WEST IS TO STEER SHOR WAVE VORTICES
ACROSS THE SOUTHEAST USA THAT ARE TO THEN FEED INTO PERSISTENT
TROUGH TO THE EAST. THE INFLOW OF SHORT WAVE ENERGY IS TO THEN
FAVOR GENERATION OF A MID LEVEL LOW THAT IS TO CLOSE NEAR THE
NORTHWEST BAHAMAS ON WEDNESDAY. AT LOW LEVELS THIS IS TO THEN
INDUCE THE NORTHWARD AMPLIFICATION OF CLIMATOLOGICAL TROUGH
PATTERN ACROSS THE CENTRAL CARIBBEAN. AXIS IS TO THEN STRETCH
NORTH FROM PANAMA TO EASTERN CUBA/SOUTHEAST BAHAMAS. ALONG THIS
AXIS A LOW IS FORECAST TO FORM NEAR THE NORTHERN BAHAMAS LATER ON
THURSDAY. MEANWHILE...THIS IS TO ENHANCE THE TRANSPORT OF DEEP
ITCZ RELATED MOISTURE ACROSS THE CENTRAL CARIBBEAN INTO
JAMAICA-EASTERN CUBA-THE BAHAMAS AND MOST OF HISPANIOLA. DURING
THE FORECAST PERIOD THE ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE
TO ORGANIZED/LONG LASTING CONVECTION TO DEVELOP. ACROSS
CUBA...JAMAICA AND THE BAHAMAS EXPECTING RAINFALL AMOUNTS OF
15-20MM/DAY AND MAXIMA OF 35-70MM. THROUGH THURSDAY THIS WILL
DECREASE TO 10-15MM/DAY AND MAXIMA OF 20-40MM. OVER
HISPANIOLA...STRONG TOPOGRAPHICAL FORCING WILL RESULT IN RAINFALL
AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM...WITH LOCALLY HIGHER
AMOUNTS HIGHLY LIKELY.

THE DEEP/HIGH AMPLITUDE TROUGH IS TO ALSO INTERACT WITH THE ITCZ
OVER COSTA RICA-PANAMA-NORTHWEST COLOMBIA. ACROSS PANAMA-COSTA
RICA/NORTHWEST COLOMBIA EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY
AND MAXIMA OF 20-40MM. ON WEDNESDAY MORNING THIS WILL INCREASE TO
15-20MM/DAY AND MAXIMA OF 35-70MM. ON THURSDAY THIS WILL DECREASE
TO MAXIMA OF 25-50MM AS BASE OF THE UPPER TROUGH STARTS TO PULL.

ANOTHER RIDGE LIES TO THE EAST...WITH UPPER AXIS FORECAST TO
EXTEND NORTH ACROSS VENEZUELA-EASTERN CARIBBEAN TO THE ATLANTIC
ALONG 65W. AS THE TROUGH HOLDS TO THE WEST...THE RIDGE IS LIKELY
TO PERSIST NEARLY UNCHANGED OVER THE NEXT FEW DAYS. AT MID LEVELS
IT IS TO ANCHOR ON A CLOSED HIGH TO THE SOUTH OF PUERTO RICO/SAINT
CROIX. IN THIS CYCLE THIS APPEARS AS A BETTER ORGANIZED/LONGER
LASTING FEATURE. THE STRONG RIDGE WILL SUSTAIN A CAP INVERSION
ACROSS THE FRENCH-LEEWARD ISLES-PUERTO RICO. THUS...EXCEPT FOR THE
OCCASIONAL STREAMERS...GENERALLY FAIR WEATHER CONDITIONS ARE TO
PREVAIL OVER THE NEXT FEW DAYS. OVER VENEZUELA...CONVECTION ALONG
THE NEAR EQUATORIAL TROUGH IS TO CLUSTER TO THE NORTH OF 04N...TO
RESULT IN RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM.
ON THURSDAY THIS WILL INCREASE TO 15-20MM/DAY AND MAXIMA OF
30-60MM AS A TROPICAL WAVE PULLS ACROSS NORTHERN SOUTH AMERICA.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC.
INITIAL    24    36    48    60    72    84    96         TYPE
49W       53W   57W   60W   63W   67W   70W    72W        TW
73W       75W   78W   80W   81W   DISSIPATES              TW

TROPICAL WAVE ALONG 49W AND SOUTH OF 10N PULLS ACROSS FRENCH
GUIANA TO SURINAME THROUGH MIDDAY ON WEDNESDAY. THIS IS TO THEN
TRIGGER MODERATE CONVECTION WITH ACCUMULATION OF 10-15MM/DAY AND
MAXIMA OF 20-45MM. EARLY ON THURSDAY IT PULLS ACROSS GUYANA TO
EASTERN VENEZUELA...WHERE IT IS TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-25MM. OVER CENTRAL VENEZUELA THIS IS
TO THEN TRIGGER RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
30-60MM AS IT INTERACTS WITH THE NEAR EQUATORIAL TROUGH. LATER IN
THE DAY ACTIVITY WILL SPREAD ACROSS WESTERN VENEZUELA TO EASTERN
COLOMBIA.

TROPICAL WAVE ALONG 73 AND SOUTH OF 15N IS TO INTERACT WITH
DEEPENING MID LEVEL TROUGH OVER THE CARIBBEAN AND THE NEAR
EQUATORIAL TROUGH OVER COLOMBIA. IN THIS AREA EXPECTING RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM. AS IT MOVES ACROSS
PANAMA THE WAVE MERGES INTO INDUCED TROUGH PATTERN OVER THE
CENTRAL CARIBBEAN...AND THROUGH THURSDAY THE WAVE BECOMES ILL
DEFINED. MEANWHILE...THIS IS TO TRIGGER RAINFALL AMOUNTS OF
15-20MM/DAY AND MAXIMA OF 35-70MM.

CARDOS...SMN (MEXICO)
CABANERIT...INAMEH (VENEZUELA)
DAVISON/GALVEZ...WPC (USA)

$$





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