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NATIONAL METEOROLOGICAL SERVICE OF BELIZE

FORECAST DISCUSSION

 

DATE: MONDAY 24TH NOVEMBER 2014 (MIDDAY)

SAT IMAGERY AND SFC OBS SUGGESTS THAT SKIES WERE MOSTLY SUNNY ACROSS THE COUNTRY THIS MORNING WITH LITTLE TO NO RAINFALL RECORDED. WATER VAPOUR LOOP SHOWS THAT CONDITIONS REMAIN DRY AT MID UPPER LEVS OVER BZE, THE YUCATAN, CNTRL AMERICA AND THE NW CARIBBEAN. LATEST PRECIP WATER ANALYSIS INDICATE LOW AVAILABLE MOISTURE WITH PWAT OF AROUND 40MM. HIGHER VALUES OF PWAT WERE NOTED A LITTLE FURTHER EAST OVER THE NW CARIBBEAN.

SFC ANALYSIS (NHC 12-Z) SHOW THAT THE MAIN FEATURE INFLUENCING OUR WEATHER CONTINUES TO BE THE RETREATING ATLC HIGH PRESSURE RIDGE. WITH BZE ON THE SW'RN PERIPHERY OF THIS SYSTEM, A DRY E-SE'LY SFC FLOW DOMINATED. A COLD FRONT WAS IN THE NW GULF OF MEXICO WITH A PREFRONTAL TROF IN THE N/CNTRL GULF. THE ATLC RIDGE DOMINATED THROUGH THE LOW LEVS (850-700B) SUPPORTING A SE'LY FLOW. AT THE UPPER LEVS, THE PERSISTENT ANTICYCLONE OVER THE NW CARIBBEAN CONTINUES TO SUPPORT A S-SW'LY FLOW ALOFT. THE UPPER PATTERN WAS WEAKLY DIVERGENT.

THE GFS (12Z) MODEL RUN FCST THE ATLC RIDGE TO CONTINUE TO SUPPORT THE E-SE'LY FLOW FOR THE NEXT 24-30 HOURS. AFTER THAT TIME, THE FRONT WILL HAVE REACHED THE SE'RN GULF/BAY OF CAMPECHE CAUSING WINDS TO BACK TO THE E-NE TOMORROW EVENING AND THEN NORTH BY WEDNESDAY MORNING. A GRADUAL AND STREADY INCREASE IN MOISTURE AND LOW LEVEL CONVERGENCE IS FCST OVER THE NEXT 24-48 HOURS. HOWEVER, THE TRAJECTORY OF THE LOW-MID LEV FLOW SUGGESTS THAT MOST OF THE SHALLOW-MOD CONVECTION APPROACHING FROM THE EAST  SHOULD MOVE NORTH OF THE COUNTRY KEEPING RELATIVELY GOOD WEATHER FOR AT LEAST THE NEXT 24-HOURS. AFTER THAT TIME, PREFRONTAL ACTIVITY WILL BEGIN TO INFLUENCE INLAND AND N'RN AREAS CAUSING SHOWERS AND THUNDERSTORMS TOMORROW AFTERNOON TO EVENING. THIS ACTIVITY WILL LIKELY SPREAD OVER THE COUNTRY ON TUESDAY NIGHT THOUGH TO WEDNESDAY MORNING. THE MODEL SUGGESTS THAT THE FRONT ITSELF WILL NOT CROSS UNTIL AROUND MIDDAY ON WEDNESDAY. THE UPPER LEVS PATTERN WILL REMAIN MOD'LY DIVERGENT FOR THE NEXT COUPLE OF DAYS AS THE S-SW'LY FLOW DOMINATES. THIS WILL LIKELY SUPPORT A FEW THUNDERSTORMS OVER THE AREA WITH THE PREFRONTAL ACTIVITY.

THE GFS GOES FOR LITTLE TO NO RAINFALL THIS AFTERNOON AND THE EARLY PARTS OF TONIGHT. AFTER THAT TIME ISOL AMOUNTS OF 0.01-0.10 INS/6HRS ARE FCST THROUGH TO MIDDAY TOMORROW. AMOUNTS THEN INCREASE WITH MAX UP TO 0.75 INS/6HRS INLAND TOMORROW AFTERNOON AND EVENING AND SPREADING OVER THE COUNTRY TUESDAY NIGHT. BY WEDNESDAY MORNING THE MAX OF 0.5 INS/6HRS IS CONFINED MOSTLY TO THE SOUTH. THE NAM GENERALLY AGREES WITH GFS DURING THE FIRST 24 HOURS BUT IT THEN GOES FOR MUCH LESS RAINFALL THAN GFS DURING THE 24-48 HOUR PERIOD.

FORECAST: MOSTLY SUNNY THIS AFTERNOON WITH LITTLE OR NO RAINFALL. PARTLY CLOUDY TONIGHT AND SUNNY WITH A FEW CLOUDY SPELLS TOMORROW MORNING. SHOWERS AND THUNDERSTORMS WILL BE GENERALLY ISOLATED.

OUTLOOK: THE APPROACH AND PASSAGE OF A COLD FRONT WILL CAUSE SOME SHOWERS, A FEW THUNDERSTORMS AND PERIODS OF RAIN TO SPREAD ACROSS THE COUNTRY STARTING OVER INLAND AND NORTHERN AREAS ON TUESDAY AFTERNOON TO COASTAL AREAS ON TUESDAY NIGHT AND SOUTHERN AREAS ON WEDNESDAY MORNING.

MARINE: WINDS: E-SE 5-15KT.;SEAS:CHOPPY; WAVES: 3-4 FT.

FORECASTER: R. Gordon