TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
332 PM EDT FRI JUL 12 2024

FORECAST BULLETIN 12 JUL 2024 AT 1930 UTC: A TROPICAL WAVE
PROPAGATING WESTWARD ACROSS THE THE EASTERN PACIFIC JUST OFF THE
COAST OF WESTERN MEXICO AND SOUTH OF BAJA CALIFORNIA WILL CAUSE
MOISTURE TO MOVE INTO THE WESTERN SECTIONS OF MEXICO TODAY AND
INTO THE WEEKEND. THIS INCREASE IN MOISTURE WILL CAUSE SOME
SHOWERS AND THUNDERSTORMS FROM JALISCO ALL THE WAY TO
SONORA...WITH MAX RAINFALL VALUES BETWEEN 25-50MM ACROSS JALISCO
AND NAYARIT...WHILE SINALOA AND SONORA WOULD HAVE MAX VALUES OF
40-80MM TODAY. EVEN THOUGH THIS TROPICAL WAVE WILL CONTINUE TO
SLOWLY MOVE WEST AND AWAY FROM LAND...PORTIONS ALONG THE SIERRA
MADRE OCCIDENTAL WILL OBSERVE SOME RAINFALL EACH DAY THIS
WEEKEND...WITH MAX TOTALS BETWEEN 20-45MM ACROSS PORTIONS OF
JALISCO TO CHIHUAHUA...AND 40-80MM ACROSS SONORA. THAT BEING
SAID...THE LATEST GUIDANCE IS FAVORING A PORTIONS OF NORTH CENTRAL
CHIHUAHUA TO OBSERVE SIGNIFICANT RAIN FROM SUNDAY INTO MONDAY DUE
TO A SFC TROUGH IN THE AREA WITH AN UPPER TROUGH CAUSING
DIVERGENCE ALOFT.

ABOVE AVERAGE MOISTURE OVER THE BAHAMAS TODAY...WITH NEAR NORMAL
MOISTURE ON SATURDAY...THEN DEEPER MOISTURE MOVING IN SLOWLY LATE
ON SATURDAY INTO SUNDAY. A SFC AND MID LEVEL LOW WILL CAUSE SOME
SHOWER AND THUNDERSTORM ACTIVITY TODAY. AN APPROACHING TROPICAL
WAVE ON SUNDAY WILL CAUSE SOME ADDITIONAL SHOWER ACTIVITY OVER THE
BAHAMAS...WHILE SATURDAY WOULD BE THE DRIEST DAY OVER THE BAHAMAS.
THE LATEST GUIDANCE SUGGESTS MAX VALUES OF RAIN SOMEWHERE BETWEEN
15 AND 25MM TODAY...UNDER 10MM ON SATURDAY...THEN UP TO 35MM ON
SUNDAY INTO MONDAY.

A TROPICAL WAVE CURRENTLY JUST EAST OF THE LESSER ANTILLES WILL
CAUSE MOISTURE TO INCREASE RAPIDLY ACROSS THE LESSER ANTILLES INTO
PUERTO RICO FROM TONIGHT INTO THIS WEEKEND. THE MID AND UPPER
LEVELS WILL ARE NOT PARTICULARLY FAVORABLE FOR STRONG THUNDERSTORM
DEVELOPMENT THIS EVENING AS A MID AND UPPER LEVEL RIDGE
DEVELOPS...BUT THE RIDGE WILL ERODE SLOWLY ON SATURDAY AND A TUTT
WILL APPROACH FROM THE EAST BY SUNDAY. THIS TUTT WILL IMPACT THE
LEEWARD ISLANDS AND PUERTO RICO STARTING EARLY ON SUNDAY. IN TERMS
OF RAINFALL AMOUNTS...GIVEN THE PERSISTENT EASTERLY WINDS AND
INCREASE IN MOISTURE...THE LESSER ANTILLES AND EASTERN PUERTO RICO
COULD OBSERVE ABOUT 25 TO 35MM OF RAIN ACROSS ISOLATED AREAS
TODAY. SATURDAY INTO SUNDAY...HISPANIOLA COULD OBSERVE MAX
RAINFALL VALUES OF 25-50MM WHILE EASTERN PR WOULD HAVE UP TO 35MM.
ON SUNDAY...UNDER 10MM ARE EXPECTED ACROSS THE LESSER
ANTILLES...PUERTO RICO COULD HAVE UP TO 45MM AND HISPANIOLA UP TO
35MM. THAT BEING SAID...THE TROPICAL WAVE THAT WOULD AFFECT THE
NORTHEAST CARIBBEAN TONIGHT INTO SATURDAY...WILL CONTINUE TO MOVE
WEST AND CROSS OVER CUBA ON SUNDAY. THIS WILL CAUSE SIGNIFICANT
RAIN OVER CUBA ON SUNDAY INTO MONDAY...WITH THE LATEST GUIDANCE
SUGGESTING MAX TOTALS OF UP TO 50MM OF RAIN...THOUGH SOME MODEL
GUIDANCE IS SUGGESTING A BIT UNDER THAT.

A SFC TROUGH WILL CAUSE SIGNIFICANT RAINFALL OVER NORTHWESTERN
SOUTH AMERICA...PARTICULARLY OVER NORTHWESTERN PERU TO EASTERN
ECUADOR...CONTINUING NORTH THROUGH COLOMBIA AND SOUTHWESTERN
VENEZUELA. DEEP MOISTURE WILL INTERACT WITH THE LOCAL TERRAIN
EFFECTS JUST EAST OF THE MOUNTAIN RANGE IN THE AREA...CAUSING
HEAVY RAIN TO DEVELOP OVER THE AREA. THE LATEST GUIDANCE IS
SUGGESTING AS MUCH AS 50-100MM OF RAIN ACROSS ISOLATED AREAS IN
THE AFOREMENTIONED REGION. ELSEWHERE ACROSS NORTHWESTERN SOUTH
AMERICA WILL OBSERVE GENERALLY RAINFALL VALUES NEAR 05-10MM WITH
MAX VALUES NEAR 20-35MM TODAY. OVERALL...THE RAINFALL ACROSS
NORTHERN SOUTH AMERICA WILL DECREASE THIS WEEKEND INTO EARLY
MONDAY...WITH DAILY RAIN NEAR 05-10MM EACH DAY AND MAX ISOLATED
AMOUNTS NEAR 15-30MM. SMALL POCKETS OF WESTERN AND EASTERN
VENEZUELA ARE FORECAST MAX VALUES BETWEEN 30 AND 80MM ON SUNDAY
INTO MONDAY.

ALAMO...(WPC)
FERNANDER...(BDM)