AFDBRO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BROWNSVILLE TX 1255 PM CDT MON APR 18 2011 .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...THE PRESSURE GRADIENT TIGHTENED ACROSS DEEP SOUTH TEXAS TODAY AS A HIGH PRESSURE RIDGE STRETCHING ACROSS THE GULF OF MEXICO INTERACTED WITH A LOW PRESSURE AREA LOCATED ACROSS OKLAHOMA. THEREFORE MODERATE AND GUSTY SOUTHEASTERLY WINDS ARE OCCURRING ACROSS THE COASTAL AND CENTRAL COUNTIES OF DEEP SOUTH TEXAS THIS AFTERNOON AND WILL CONTINUE AT THOSE LEVELS THROUGH THE EARLY EVENING. THE WINDS WILL DECREASE OVERNIGHT BECOMING MODERATE FROM THE SOUTHEAST. MODERATE AND GUSTY SOUTHEASTERLY WINDS WILL PREVAIL ACROSS THE RIO GRANDE VALLEY AGAIN TUESDAY WITH THE HIGHER WINDS OCCURRING ACROSS THE COASTAL AND CENTRAL COUNTIES OF DEEP SOUTH TEXAS. THE TEMPERATURES WILL CONTINUE ABOVE NORMAL FOR THIS TIME OF THE YEAR FOR THE NEXT FEW DAYS. DRY CONDITIONS WILL PREVAIL ACROSS THE RIO GRANDE VALLEY THROUGH TUESDAY NIGHT. .LONG TERM /WEDNESDAY THROUGH TUESDAY/...STEADY STATE ZONAL FLOW ACROSS NORTH AMERICA WILL KEEP DEEP SOUTH TEXAS UNDER A WARM SOUTHERLY AND INCREASINGLY HUMID AIR MASS. FLAT UPPER RIDGE OVER MEXICO AND THE SOUTHERN GULF TO KEEP THE JET STREAM WELL NORTH OF OUR CWA. WEAK DISTURBANCES IN THIS STEADY WEST TO EAST FLOW WILL INTERMITTENTLY INCREASE THE WINDS TO WINDY CONDITIONS FROM THE NORMAL AFTERNOON BREEZES. ONE DISTURBANCE APPROACHES THE SOUTHERN PLAINS THURSDAY AND PASSES EAST FRIDAY WITH THE NEXT ONE ON TAP FOR SUNDAY. SHALLOW MOISTURE TO KEEP THE AREA HUMID WITH EXCEPTION TO THE AFTERNOON HOURS ACROSS THE BRUSH COUNTRY WHERE DRY AIR ALOFT WILL MIX TO THE SURFACE LOWERING AFTERNOON HUMIDITY. CLOUD COVER WILL BE TYPICAL FOR MID APRIL WITH MOSTLY CLOUDY NIGHTS AND MOSTLY CLEAR TO PARTLY CLOUDY DAYS THANKS TO THE PERSISTENT GULF FLOW. TEMPERATURES WILL CONTINUE TO BE AT OR ABOVE SEASONAL NORMALS WITH THE UPPER RIDGE CLOSE TO OUR VICINITY AND YES THE SOUTH WINDS KEEPING OUR OVERNIGHT LOWS ELEVATED. ALSO THE EVER INCREASING GULF OF MEXICO WATERS WHICH ARE NOW IN THE LOW TO MID 70S WILL MAINTAIN BALMY EVENINGS. ONE ITEM TO WATCH FOR IN THE COMING DAYS AREA THUNDERSTORMS THAT COULD DEVELOP ALONG THE SIERRA MADRE MOUNTAINS AND ALONG THE DRY LINE THAT WILL LIE ACROSS SOUTHWEST TEXAS EXTENDING INTO MEXICAN PLATEAU. GFS AND ECMWF CONTINUES TO INDICATE THIS ACTIVITY BECOMING MORE ENHANCED WITH TIME ESPECIALLY WHEN ONE OF THE UPPER SHORTWAVES APPROACHES THE AREA. IF THE STRONG CAP OVER THE REGION DOES NOT BREAK THEN THESE STORMS DO NOT HAVE A CHANCE TO WORK THERE WAY OVER THE RIVER...BUT IF A DISTURBANCE DOES TREND FARTHER SOUTH AND EAST THEN THERE MIGHT BE A CHANCE FOR A STORM OR TWO. WE ARE GETTING CLOSE TO MAY AND THIS TREND STARTS TO BECOME MORE COMMON ESPECIALLY WITH THE INTENSE SURFACE HEATING ADDING TO LARGE LAPSE RATES AND THE DEEPENING GULF MOISTURE. && .MARINE...AT NOON BUOY 20 REPORTED SOUTH WINDS AT 12 KNOTS WITH GUSTS TO 16 KNOTS AND SEAS AT 3.9 FEET WITH A 6 SECOND PERIOD. THE WINDS AND SEAS WILL INCREASE ACROSS THE OFFSHORE GULF OF MEXICO COASTAL WATERS OVERNIGHT AND TUESDAY. THEREFORE SMALL CRAFT ADVISORIES WILL BE IN EFFECT ACROSS THE OFFSHORE GULF OF MEXICO COASTAL WATERS OVERNIGHT TONIGHT THROUGH NOON TUESDAY AND MAY NEED TO BE EXTENDED ON TUESDAY. SMALL CRAFT ADVISORIES FOR WINDS WILL CONTINUE ACROSS THE LAGUNA MADRE AND NEAR SHORE GULF OF MEXICO COASTAL WATERS THROUGH 7 PM THIS EVENING. SMALL CRAFT ADVISORIES FOR WINDS WILL BE IN EFFECT ACROSS THE LAGUNA MADRE ON TUESDAY FROM 10 AM THROUGH 7 PM DUE TO THE INCREASING WINDS. WEDNESDAY THROUGH SUNDAY...MODERATE TO STRONG SOUTHERLY FLOW TO PRODUCE PERIODIC SMALL CRAFT CONDITIONS ACROSS THE COASTAL WATERS. THE INCREASING DURATION OF THE STRONGER SOUTH WINDS WILL TREND TO KEEP SEAS ELEVATED AND THE ADVISORIES COULD EXTEND LONGER. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 75 87 77 87 / 0 0 0 10 BROWNSVILLE 75 88 76 91 / 0 0 0 10 HARLINGEN 75 93 75 93 / 0 0 0 10 MCALLEN 75 93 75 95 / 0 0 0 10 RIO GRANDE CITY 72 96 74 98 / 0 0 0 10 SOUTH PADRE ISLAND 75 82 77 81 / 0 0 0 10 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 7 PM CDT THIS EVENING FOR GMZ130-132-135-150-155. SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM TO 7 PM CDT TUESDAY FOR GMZ130-132-135. SMALL CRAFT ADVISORY FROM 1 AM TO 1 PM CDT TUESDAY FOR GMZ150- 155-170-175. && $$