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NATIONAL METEOROLOGICAL SERVICE OF BELIZE

FORECAST DISCUSSION

  

DATE: THURSDAY 3RD SEPTEMBER 2015 (AFTERNOON)

SAT IMAGERY (VIZ) AND RADAR OBS SHOWED A FEW SHOWERS / POSSIBLE ISOLATED THUNDERSTORMS AFFECTED S'RN AND INLAND AREAS THIS MORNING THEN DISSIPATED AFTER MID-MORNING. WV IMAGERY DETECTED SOME DRY AIR ACROSS YUCATAN - GUATEMALA - BZE AND COASTAL WATERS WHILE MOISTURE WAS FLOWING CYCLONICALLY ACROSS THE W'RN GLF - S'RN MEXICO - CENTRAL AMERICA AND THE CANTRAL CARIBBEAN WITH A LOW BETWEEN JAMAICA AND NE'RN HONDURAS. LATEST MIMIC-PW IMAGE (14Z) SHOWED MOD AMTS OF AVAILABLE MOISTURE OVER OUR AREA IN THE RANGE OF 45-55mm. 

SFC ANALYSIS (HPC - 03 / 12Z) HAD A TROPICAL WAVE ALONG 83W SOUTH OF 17N AND ANOTHER NEAR 46W/47W. A WEAK HIGH (1016hPa) OVER THE NE'RN GLFMEX AND THERMAL TROUGH / HEAT LOWS OVER MAINLAND MEXICO SUPPORTS A MOD E'LY - ESE'LY FLOW OVER OUR AREA. A RIDGE CENTERED OVER W'RN FLORIDA AND THE NE'RN GLFMEX DOMINATED FROM LOW - UPPER LVLS OF THE ATMOSPHERE. A TUTT DOMINATED THE CARIBBEAN WITH LOW OVER NORTHEAST AND W'RN CARIBBEAN AND ANOTHER OVER THE WEST / CENTRAL GLFMEX. THE FLOW WAS E'LY - ESE'LY AT LOW - MID LVLS BECMG N'LY - NNW'LY AT UPPER LVLS. THE PATTERN WAS NEUTRAL - WEAKLY DIVERGENT OVER BZE.   

 

THE TROPICAL WAVE IS EXPECTED TO CROSS CENTRAL AMERICA TO THE SOUTH LATER TONIGHT / EARLY TOMORROW. THE GFS (00Z / 12Z) MODEL RUNS FCST THE LOW - MID LVL RIDGE TO CONTINUE DOMINATING OVER OUR AREA AS THE HIGH MEANDERS SE'WARDS FROM THE GLFMEX TO THE N'RN CARIBBEAN. AN E'LY - ESE'LY FLOW IS TO PREVAIL AT THE SFC THRU LOW AND MID LVLS DURING THIS 3-DAY CYCLE. THE GFS FCST WEAK LOW LVL CONVERGENCE WITH LIMITED LOW LVL MOISTURE TO CONFINE BELOW 800-850hPa THRU TOMORROW. MOISTURE IS TO BE A BIT HIGHER OVER THE SOUTH AND TO INCREASE SLIGHTLY TOMORROW NIGHT / EARLY SAT. BEFORE A DRY LAYER SETS IN. AT UPPER LVLS THE TUTT LOW IS TO MIGRATE SLOWLY ACROSS N'RN BZE - YUCATAN THRU TOMORROW THEN WEAKEN TO AN OPEN TROUGH OVER THE E'RN BAY OF CAMPECHE THRU THE END OF THE CYCLE. THE N'LY FLOW IS TO BACK TO NW'LY TODAY THEN BECMG SW'LY TONIGHT THRU THE END OF THE 3-DAY CYCLE. WEAK CONVERGENCE IS TO DEVELOP OVER-NIGHT THEN THE SW'LY FLOW PATTERN BECMGS WEAKLY DIVERGENT TOMORROW THRU THE END OF THE CYCLE.   

THE GFS SUGGEST RR AMTS MOSTLY OF .10-.25-/6hrs THE NEXT 2-3 DAYS WITH MAX OF .50ins TO OCCUR IN THE SOUTH AT NIGHT-TIME. THE NAM GOES FOR .10-.25ins/6hrs AND AGAIN THE HIGHER VALUES ARE TO OCCUR IN THE SOUTH AT NIGHT. THE NVG SHOWS A GRADUAL INCREASE IN RR AMTS TOMORROW THRU SAT TO PEAK SAT NIGHT AT 18-25mm/12hrs. THE HIGHER RESOLUTION WRF ALSO SUGGEST INCREASED ACTIVITY IN THE SOUTH AT NIGHT.   

FORECAST:  SUNNY WITH A FEW CLOUDY SPELLS DURING THE DAYTIME AND PARTLY CLOUDY TONIGHT. SHOWERS AND THUNDERSTORMS WILL BE GENERALLY ISOLATED, EXCEPT FOR A FEW MORE IN THE SOUTH TONIGHT.

OUTLOOK: SOME CLOUDY SPELLS WITH ISOLATED SHOWERS AND THUNDERSTORMS FRI AFTERNOON, THEN A FEW SHOWERS AND THUNDERSTORMS MOSTLY OVER THE SOUTH AND ALONG SOME COASTAL AREAS FRI NIGHT AND SAT MORNING.

MARINE:  WINDS: E-SE 10-20 KTS.; SEAS:  CHOPPY - MODERATE.; WAVES: 3-5 FT. 

FORECASTER:  M.  GENTLE.