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NATIONAL METEOROLOGICAL SERVICE OF BELIZE

FORECAST DISCUSSION

DATE: SUNDAY 27 JULY 2014 (EVENING)  

SAT IMAGERY (VIZ) AND RADAR OBS SHOWED ISOLATED SHOWERS AFFECTED THE SOUTH THIS AFTERNOON AND EVENING WHILE THE REM OF THE COUNTRY HAD MAINLY FAIR WX CONDITIONS. DEEP CONVECTION FLARED-UP OVER HONDURAS / GUATEMALA THIS AFTERNOON BUT HAS STARTED TO DISSIPATE (WARMING CLOUD TOPS) DUE TO THE LOSS OF DAYTIME HEATING. WV IMAGERY DETECTED SOME MOISTURE BEING DRAWN NE'WARDS AND NORTH ACROSS N'RN CENRAL AMERICA BY A TUTT / LOW OVER THE SE'RN GLF AND EAST - CENTRAL MEXICO. MOIST CONDITIONS ALSO PREVAILED ACROSS S'RN MEXICO - THE REM OF CENTRAL AMERICA AND THE SW'RN CARIBBEAN. LATESTIMIC-PW IMAGE (22Z) SHOW AVAILABLE MOISTURE IN THE RANGE OF 47-57mm OVER THE W'RN HALF OF THE CARIBBEAN TO NEAR BZE.  

SFC ANALYSIS (TPC-27 / 18Z) HAD A HIGH PRESSURE RIDGE BETWEEN 18N AND 23N FROM THE N'RN ATLANTIC ACROSS THE GLFMEX WITH A HIGH (1020hPa) OVER THE NORTH / CENTRAL GLF. THE TROPICAL WAVE WAS ADJUSTED WEST TO ALONG 74W SOUTH OF 18N AND THE SFC PATTERN SUPPORTED A LIGHT ENE'LY FLOW OVER OUR AREA. THE RIDGE WAS ALSO EVIDENT THROUGH THE LOW - MID LVLS AND THE FLOW CONTINUED GENERALLY E'LY. AT UPPER LVLS A BROAD OPEN TROUGH OVER THE CENTRAL GLF TO W'RN YUCATAN SUPPORTS A SE'LY - S'LY FLOW AT 300hPa WHILE AT 200hPa THE FLOW WAS W'LY - SW'LY DUE TO THE CUT-OFF LOW. THE UPPER LVL PATTERN WAS NEUTRAL TO WEAKLY CONVERGENT. 

THE GFS (12Z / 18Z) MODEL RUNS FCST THE SFC FLOW TO BE E'LY - ENE'LY DURING THE CYCLE WHILE AT LOW LVLS THE E'LY FLOW VEERS TO THE SOUTHEAST ACCOMPANIED BY A WEAK SURGE BY TUES MORNING. THIS IS SUGGESTING A POSSIBLE WAVE CROSSING. HOWEVER, THE GFS IS FCSTNG AN INCREASE IN LOW LVL CONVERGENCE OVER-NIGHT - TONIGHT WITH A SURGE IN MOISTURE AFTER MID-NIGHT THROUGH MID-DAY TUES. A RAPID DECREASE IN MOISTURE / CONVERGENCE IS FCST AFTER. AT UPPER LVLS THE INVERTED TROUGH AT 300hPa AND LOW AT 200hPa ARE TO DRIFT W'WARDS ACROSS MEXICO AS A DIGGING E-W TROUGH EXTENDS ACROSS YUCATAN LATER TOMORROW THROUGH THE END OF THE CYCLE. WITH THE AXIS TO THE NORTH UPPER LVL DIVERGENCE IS FCST TO INCREASE LATER TONIGHT THROUGH TOMORROW NIGHT AND THIS IS EXPECTED TO PROVIDE SUPPORT FOR MOD - DEEP CONVECTION DURING THE APPROACH AND PASSAGE OF THE TROPICAL WAVE.

THE GFS FCTS RR AMTS OF .50-.75ins/6hrs MOSTLY ALONG THE SOUTH COAST LATER TONIGHT THROUGH TOMORROW NIGHT THEN DECREASING AFTER. THE NAM FCST .25-.5ins/6hrs TOMORROW THROUGH EARLY TUES OVER THE SAME AREAS WHILE THE NVG HAS A SLIGHT INCREASE OF 4-8mm/6hrs TOMORROW AND A MORE PRONOUNCED INCREASE OF 8-18mm/6hrs THROUGH TUES NIGHT. 

FORECAST: CLOUDY SPELLS WITH SOME SHOWERS AND A FEW THUNDERSTORMS MOSTLY OVER SOUTHERN AND SOME COASTAL AREAS TONIGHT THEN OVER MOST AREAS TOMORROW.

EXTENDED: SOME CLOUDY SPELLS WITH A FEW SHOWERS AND ISOLATED THUNDERSTORMS MOSTLY ALONG THE COAST MON NIGHT DECREASING DURING TUES.. 

MARINE: WINDS: E-NE 10-20 KTS.;  SEAS: CHOPPY - MODERATE.; WAVES: 3-6 FT. 

FORECASTER:   M.  Gentle