TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
258 PM EDT MON JUL 15 2024

FORECAST BULLETIN 15 JUL 2024 AT 1830 UTC: ACROSS THE TROPICAL
REGION...THERE IS A STRONG SFC HIGH PRESSURE DOMINATING THE
ATLANTIC...AS WELL AS A STRONG SFC HIGH ACROSS THE EASTERN PACIFIC
TO THE WEST OF BAJA CALIFORNIA. OTHERWISE...THERE ARE A FEW WEAKER
SFC LOWS OVER SOUTHERN MEXICO AND WESTERN COLOMBIA. A FEW SFC LOWS
COULD ALSO DEVELOP ALONG THE MONSOON TROUGH IN THE PACIFIC OVER
THE NEXT FEW DAYS AS WELL. SEVERAL TROPICAL WAVES ARE BEING
OBSERVED OVER THE TROPICS...THOUGH THE NATIONAL HURRICANE CENTER
DOES NOT HAVE ANY AREAS WITH POSSIBLE TROPICAL CYCLONE FORMATION
IN THEIR TROPICAL WEATHER OUTLOOK.

IN THE UPPER LEVELS...AN UPPER LOW WILL PERSIST OVER THE NEXT 3
DAYS ACROSS THE WESTERN TROPICAL ATLANTIC...AND ANOTHER UPPER
TROUGH IS DEVELOPING FROM THE AFOREMENTIONED UPPER LOW INTO THE
WESTERN CARIBBEAN. THIS UPPER LOW AND TROUGH WILL MEANDER OVER THE
AREA FOR THE NEXT FEW DAYS...WHICH WILL CAUSE SOME CONVECTION TO
DEVELOP TO THE SOUTH AND EAST OF ITS AXIS. HOWEVER...MOST OF THIS
CONVECTION COULD ACTUALLY BE OVER WATER...WITH THE CONVECTION OVER
LAND BEING SOMEWHAT LIMITED DUE TO LIMITED MOISTURE. THE DEEPER
MOISTURE IS LOCATED ALONG THE ITCZ AND MONSOON TROUGH. THE MONSOON
TROUGH IN THE EASTERN PACIFIC AND THE SFC LOW OFF THE COAST OF
WESTERN COLOMBIA WILL BRING PERSISTENT MOISTURE OVER PORTIONS OF
COSTA RICA...PANAMA..AND WESTERN COLOMBIA FOR THE NEXT FEW DAYS.
THIS WILL RESULT IN THE POSSIBILITY OF SHOWERS AND THUNDERSTORMS
WHEN THE MOISTURE COMBINES WITH THE DIURNAL HEATING AND LOCAL
TERRAIN EFFECTS. IT IS ALSO WORTH MENTIONING...THAT OVER CENTRAL
AMERICA...THE PRECIPITABLE WATER VALUES WILL BE BETWEEN 50 AND
65MM ALONG THE COAST AS WELL AS SOME PLACES OVER LAND. THE DEEPEST
MOISTURE...THAT IS CLOSER TO 65MM WILL BE IN AND AROUND COSTA RICA
AND PANAMA...AS WELL AS SOUTHEASTERN NICARAGUA. THEREFORE...THIS
AREA WILL HAVE PERSISTENT DEEP MOISTURE AVAILABLE FOR THE
DEVELOPMENT OF SHOWER ACTIVITY.

ACROSS NORTHERN SOUTH AMERICA...SEVERAL SFC TROUGHS WILL BE
PRESENT OVER THE WEEK...WHICH WILL ALSO HELP IN THE DEVELOPMENT OF
SHOWERS AND THUNDERSTORMS OVER THE AREA. PORTIONS OF VENEZUELA AND
GUYANA ARE FORECAST TO OBSERVE THUNDERSTORMS TODAY AND ON TUESDAY
INTO WEDNESDAY. TODAY WILL HAVE THE HIGHEST AMOUNTS OF RAIN...WITH
THE GFS SUGGESTING ISOLATED MAXIMA UPWARDS OF 100MM OVER EASTERN
VENEZUELA INTO GUYANA. TUESDAY INTO WEDNESDAY...CENTRAL VENEZUELA
COULD HAVE AS MUCH AS 75MM IN ISOLATED AREAS...BUT LIGHTER SHOWER
ACTIVITY IS EXPECTED ON WEDNESDAY INTO THURSDAY. HOWEVER...WESTERN
COLOMBIA WILL HAVE MODEST AMOUNTS OF RAIN TODAY...BUT TUESDAY AND
WEDNESDAY COULD BE WETTER...AS THE SFC LOW PULLS MOISTURE INTO THE
CONTINENT AND THE MOIST ONSHORE FLOW CAUSES SHOWER AND
THUNDERSTORM ACTIVITY. SOME OF THE SHOWER ACTIVITY ACROSS COLOMBIA
COULD BE AS MUCH AS 40-80MM ON WEDNESDAY INTO EARLY THURSDAY.

ACROSS THE GREATER ANTILLES...LOCALIZED CONVECTION IN THE
PERIPHERY OF THE UPPER LOW IS EXPECTED...AS THE AVAILABLE MOISTURE
COMBINES WITH THE UPPER LEVEL DYNAMICS...LOCAL OROGRAPHIC EFFECTS
AND DIURNAL HEATING. THIS LOCALIZED CONVECTION COULD RESULT IN
ISOLATED MAX RAINFALL TOTALS OF NEAR 50MM OVER SOUTHERN HISPANIOLA
AND SOUTHEAST CUBA TODAY. TUESDAY AND WEDNESDAY WILL HAVE MUCH
MORE MODEST RAINFALL AMOUNTS OVER THE GREATER ANTILLES AS DRIER
AIR MOVES IN. THERE IS A SHORTWAVE TROUGH THAT MOVES INTO THE
CARIBBEAN ON WEDNESDAY...NEAR 70W BY WEDNESDAY EVENING...BUT THE
DEEPEST MOISTURE ASSOCIATED WITH IT WILL BE TO THE SOUTH OF THE
ISLANDS.

MEXICO WILL HAVE NEAR TO ABOVE NORMAL PRECIPITABLE WATER VALUES
FOR THE NEXT SEVERAL DAYS. THIS MOISTURE WITH LOW LEVEL
CONVERGENCE AND DIURNAL HEATING WILL CAUSE AREAS OF SHOWERS AND
THUNDERSTORMS OVER A LARGE PORTIONS OF MEXICO EACH DAY. RAINFALL
TOTALS OF 10-15MM WITH ISOLATED MAX BETWEEN 20-50MM COULD BE
EXPECTED EACH DAY ACROSS MANY SECTORS OF MEXICO...ESPECIALLY IN
THE CENTRAL TO WESTERN SECTIONS. ON WEDNESDAY INTO THURSDAY...AN
UPPER HIGH PRESSURE OVER MEXICO AND AN UPPER LOW OVER TEXAS WILL
CAUSE A RELATIVELY STRONGER JET OVER CENTRAL TO NORTHEASTERN
MEXICO...WHICH WILL CAUSE THE THUNDERSTORM DEVELOPMENT TO EXPAND
INTO NORTHEASTERN MEXICO. THAT BEING SAID...THE GLOBAL MODEL
GUIDANCE IS NOT IN AGREEMENT WITH THE RAINFALL TOTALS...THE GFS
BEING VERY SHY WITH ITS AMOUNTS OF RAIN. HOWEVER...GIVEN THE ABOVE
NORMAL MOISTURE AND THE MID TO UPPER LOW AS WELL AS THE STRONGER
WINDS ALOFT...IT WOULD BE DIFFICULT TO HAVE VERY LITTLE RAIN...FOR
THAT REASON THE FORECAST SUGGESTS MAXIMA OF UP TO 35MM FOR THAT
AREA OF MEXICO ON WEDNESDAY INTO THURSDAY...BUT WILL CONTINUE TO
MONITOR FOR ADJUSTMENTS IN THE MODEL GUIDANCE. 



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