475  
FXUS62 KMFL 190714  
AFDMFL  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MIAMI FL  
314 AM EDT FRI JUL 19 2019  
   
DISCUSSION
 
 
A WARM, WET, AND UNSETTLED PATTERN APPEARS TO BE IN THE FORECAST  
OVER THE COMING WEEK. WITH SOUTH FLORIDA IN THE MIDST OF SUMMER, WE  
CERTAINLY ARE SEEING AN INTERESTING PATTERN WITH A TROUGH OVER THE  
EASTERN SEABOARD OF THE UNITED STATES AND AN AREA OF HIGH PRESSURE  
OVER THE ATLANTIC FOR MUCH OF THE FORECAST PERIOD. THESE FEATURES,  
HOW THEY INTERACT, AND HOW SOME OTHER SMALLER FEATURES IN TURN  
INTERACT WILL LEAD TO MUCH OF THE DAY-TO-DAY SHIFTS IN THE FORECAST  
FOR OUR AREA.  
 
TODAY: WITH THE DEPARTURE OF THE MID-LEVEL TROUGH INTO THE GULF OF  
MEXICO, TODAY'S CONVECTIVE PATTERN WILL BE MORE CONFINED TO THE  
NORMAL DIURNALLY DRIVEN SEA BREEZE FOCUS TYPICAL OF SUMMERS IN  
SOUTHERN FLORIDA. OVERNIGHT AND MORNING CONVECTION OVER THE ATLANTIC  
COASTAL WATERS WILL HAVE A CHANCE OF PUSHING OVER THE EAST COAST  
METRO. EVENTUALLY THE SEA BREEZE CIRCULATIONS WILL DEVELOP AND PUSH  
INLAND, SHIFTING THE CONVECTIVE FOCUS ALONG WITH THEM. THE GENERAL  
SOUTHEASTERLY FLOW WILL ONCE AGAIN FAVOR THE INTERIOR AND GULF COAST  
FOR THE HIGHER RAIN AND STORM CHANCES THIS AFTERNOON AND EVENING.  
TEMPERATURES WILL HAVE A CHANCE TO REBOUND INTO THE LOWER TO MID 90S  
TODAY SINCE CONVECTION WILL NOT GET STARTED AS EARLY TODAY AS IT DID  
DUE TO THE PRESENCE OF THE MID-LEVEL TROUGH ON THURSDAY.  
 
SATURDAY: DIURNAL/SEA BREEZE CONVECTION WILL BE ON TAP AGAIN ON  
SATURDAY, PARTICULARLY IN THE AFTERNOON. THINGS BEGIN TO EVOLVE LATE  
IN THE DAY INTO THE OVERNIGHT AS A TROUGH APPROACHES FROM THE  
BAHAMAS. THE HEART OF THIS TROUGH WILL BE AT THE MID-LEVELS WHERE A  
DECENT SIGNAL IS THERE NOT ONLY WITH THE HEIGHT FIELDS BUT ALSO THE  
VORTICITY FIELDS. THE MOISTURE MAY TRAIL THE TROUGH SLIGHTLY, BUT  
ONCE IT ARRIVES WE COULD SEE CONVECTION FLARE UP OVER THE ATLANTIC  
WATERS ON SATURDAY NIGHT UNRELATED TO THE DIURNAL CONVECTION EARLIER  
IN THE DAY. AS THIS CONVECTION REACHES SOUTH FLORIDA OVERNIGHT INTO  
EARLY SUNDAY MORNING, THE RISK OF HEAVY RAINFALL WILL NEED TO BE  
MONITORED.  
 
SUNDAY: THE PATTERN FOR SUNDAY WILL ONCE AGAIN DEPART FROM THE PURE  
DIURNALLY DRIVEN SEA BREEZE FOCUS AS THE TROUGH MOVES INTO THE  
SOUTHERN PENINSULA OF FLORIDA. THE PRESENCE OF THE TROUGH COULD  
ALLOW CONVECTION ON SUNDAY TO FEATURE A BIT MORE OF A KICK THAN ON  
EITHER FRIDAY OR SATURDAY. HEAVY RAINFALL AND GUSTY WINDS ARE BOTH  
CONCERNS OVER THE FORECAST AREA ON SUNDAY. THE POTENTIAL DEVELOPMENT  
OF A COINCIDENT SURFACE SIGNAL WITH THIS MID-LEVEL TROUGH, SUCH AS A  
SURFACE TROUGH OR LOW, COULD PROVIDE A BETTER ENVIRONMENT FOR  
SURFACE-BASED CONVECTION TO DEVELOP AND PERSIST ON SUNDAY.  
 
THE COMING WEEK: THE TROUGH PUSHES WEST-NORTHWEST ACROSS SOUTH  
FLORIDA EARLY MONDAY, REACHING THE EASTERN GULF OF MEXICO BY LATE  
MONDAY. MEANWHILE, A SURFACE TROUGH PUSHES INTO THE NORTHERN BAHAMAS  
ON MONDAY INTO TUESDAY WITH SOME ADDITIONAL TROPICAL MOISTURE. AS  
THIS ENTERS OUR REGION, THE LARGE SCALE TROUGH OVER THE EASTERN  
SEABOARD WILL BEGIN TO AMPLIFY SOUTHWARD ON TUESDAY. THE INTERACTION  
BETWEEN THE APPROACHING MID-LATITUDE TROUGH, THE TROPICAL EASTERLY  
TROUGH, AND THE TROPICAL MOISTURE COULD SERVE TO INCREASE RAIN  
CHANCES IN THE AREA BEGINNING ON TUESDAY. AS THE MID-LATITUDE TROUGH  
AMPLIFIES AND SHIFTS SOUTHEASTWARD, THE HIGH WILL ERODE ALLOWING FOR  
A MORE UNSETTLED PATTERN ACROSS THE STATE AND MUCH OF THE SOUTHEAST  
UNITED STATES THROUGH THE END OF THE EXTENDED FORECAST PERIOD. ONCE  
AGAIN THE MAJOR CONCERN IS THE POTENTIAL FOR HEAVY RAINFALL THOUGH  
GUSTY WINDS CANNOT BE RULED OUT EITHER.  
 

 
   
MARINE
 
 
A RIDGE OF HIGH PRESSURE WILL CONTINUE TO DOMINATE THE WEATHER  
PATTERN THROUGH THE WEEKEND ALLOWING FOR A SOUTHEASTERLY FLOW TO  
CONTINUE. SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH  
DAY. AN EASTERLY WAVE COULD PUSH INTO THE ATLANTIC WATERS LATE IN  
THE WEEKEND AND EARLY NEXT WEEK. THIS COULD INCREASE THE CHANCES  
OF SHOWERS AND THUNDERSTORMS DURING THIS TIME FRAME.  
 

 
   
PREV DISCUSSION
 
/ISSUED 135 AM EDT FRI JUL 19 2019/  
 
AVIATION...  
SCATTERED SHRA MOVING ONSHORE IN VICINITY OF EAST COAST SITES  
PERIODICALLY THROUGH ABOUT 16Z, FIRST IN MIA-FLL AREA EARLY THIS  
AM, THEN SHIFTING TO PBI AREA BY ABOUT 13Z. VCSH SHOULD COVER THE  
EXPECTED PATTERN, WITH PERIODS OF MVFR CONDITIONS POSSIBLE WITH  
MORE CONCENTRATED SHOWERS NEAR THE AIRFIELDS. AN ISOLATED TS IS  
NOT OUT OF THE QUESTION EAST COAST, BUT NOT ENOUGH CONFIDENCE TO  
PUT IN FORECAST. SCATTERED SHOWERS/TS THEN DEVELOPING OVER THE  
INTERIOR PENINSULA AND MOVING NW TO VICINITY GULF COAST 16Z-00Z.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
WEST PALM BEACH 90 79 90 79 / 30 20 20 30  
FORT LAUDERDALE 89 81 89 80 / 20 20 20 30  
MIAMI 90 81 90 80 / 20 20 20 30  
NAPLES 90 76 90 76 / 40 20 50 30  
 

 
   
MFL WATCHES/WARNINGS/ADVISORIES
 
 
FL...NONE.  
AM...NONE.  
GM...NONE.  
 

 
 
DISCUSSION...02/RAG  
MARINE...02/RAG  
AVIATION...59/RM  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab FL Page Main Text Page