221 FXUS64 KLCH 072237 AFDLCH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAKE CHARLES LA 437 PM CST MON MAR 7 2016 ...SIGNIFICANT RAIN EVENT EXPECTED TUESDAY INTO THURSDAY... .SYNOPSIS... AN UPPER LVL TROF WAS ENTERING THE WEST COAST UPSTREAM OF A BROAD RIDGE OVER THE ERN CONUS PER THE LATEST WV IMAGERY AND UA ANALYSIS. AT THE SFC...HIGH PRES WAS CNTRD OVER THE CAROLINAS WITH LOWER PRES DEVELOPING IN THE VCNTY OF A DRYLINE ACRS WRN TX. IN BETWEEN...GUSTY SLY WINDS HAVE BECOME ESTABLISHED AND DECENT LOW LVL MOISTURE RETURN HAS BROUGHT AN ABUNDANCE OF CLOUDS BACK OVER THE AREA...RESULTING IN A WARM WINDY AND MUGGY DAY ACRS THE AREA. REGIONAL RADAR MOSAIC SHOWS SHOWERS AND TSTMS ALREADY DEVELOPING ACRS CNTL/NRN TX IN ADVANCE OF THE UPSTREAM TROF. && .DISCUSSION... SIGNIFICANT CHANGES ARE ON THE WAY THE NEXT FEW DAYS AS THE UPR TROF OVER THE WEST DIGS TO THE SE...SHARPLY AMPLIFYING AND CUTTING OFF INTO A CLOSED LOW OVER NW MEXICO. DISTURBANCES ROUNDING THE BASE OF THE CUTOFF LOW ARE SPREADING SHOWERS AND STORMS ACRS TX...MAINLY WEST OF THE REGION TODAY...BUT ACTIVITY WILL BEGIN TO SPREAD EAST INTO SE TX BY EARLY TUESDAY. UNFORTUNATELY...THE UPR LOW WILL BECOME STALLED OVER NRN MEXICO THROUGH THE MIDDLE TO LATTER PART OF THE WEEK...MEANDERING OVER THE RIO GRANDE VALLEY. THIS WILL LEAD TO A PERSISTENT AREA OF LOW PRES DEVELOPING ACRS TX. NUMEROUS WEATHER HAZARDS ARE EXPECTED OVER THE NEXT FEW DAYS AND WILL BE ADDRESSED INDIVIDUALLY: FIRST...DEEPENING SLY FLOW WILL FUNNEL ABUNDANT GULF AND CARIBBEAN MOISTURE INTO THE AREA. PW VALUES WILL RAMP UP SHARPLY...INCREASING FM JUST UNDER AN INCH TONIGHT TO NR 1.7 INCHES BY MIDDAY TUESDAY. THE COMBINATION OF COPIOUS MOISTURE...A SLOW MOVING LOW ALOFT AND SERIES OF DISTURBANCES EJECTING OUT FM THE LOW WILL LEAD TO SEVERAL PERIODS OF SHOWERS AND STORMS...WITH HEAVY RAINFALL POSSIBLE IN SOME OF THE STORMS. DESPITE THE ANTECEDENT DRY CONDITIONS ACROSS THE AREA...THESE REPEATED PERIODS OF RAINFALL WILL QUICKLY LEAD TO SATURATED SOILS AND THE POTENTIAL FOR WIDESPREAD FLOODING POSSIBLY BY WEDNESDAY. RAINFALL TOTALS OF 6 TO 10 INCHES ARE EXPECTED BETWEEN TUESDAY AND THURSDAY...WITH LOCALLY HIGHER AMOUNTS POSSIBLE. A FLASH FLOOD WATCH HAS BEEN ISSUED FOR AT LEAST THE WRN HALF OF THE AREA...WHERE SOME OF THE HIGHEST AMOUNTS ARE EXPECTED AT THIS TIME. SECOND...THERE IS THE POTENTIAL FOR STRONG TO SEVERE STORMS. DECENT INSTABILITY WILL BE ACRS THE AREA TUESDAY...BCMG MORE LIMITED BY WEDNESDAY DUE TO THE ONGOING RAINFALL AND CLOUD COVER. HOWEVER...DECENT LOW LVL SHEAR WITH BULK SHEAR VALUES BETWEEN 30 AND 40 KT TUESDAY INTO WEDNESDAY WILL ALLOW FOR SOME STORMS TO PRODUCE DAMAGING WINDS OR POSSIBLY ISLTD TORNADOES. THIRD...OUTSIDE OF SVR WEATHER...STRONG GRADIENT WINDS WILL ALSO AFFECT THE AREA AS THE REGION REMAINS SANDWICHED BETWEEN HIGH PRES TO THE EAST AND A PERSISTENT LOW OVER TX. WIND ADVISORIES LOOK LIKELY FOR THE AREA TUESDAY INTO WEDNESDAY...WITH GUSTS TO BETWEEN 30 TO 40 MPH AT TIMES. LASTLY...THERE IS ALSO A THREAT OF COASTAL FLOODING FROM LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. THE STRONG ONSHORE FLOW WILL ALLOW WATER TO BEGIN PILING UP ALONG THE COAST...LEADING TO ELEVATED WATER LEVELS ESPECIALLY DURING TIME OF HIGH TIDE. TIDE LEVELS ARE EXPECTED EXCEED 3.0 FEET MEAN LOWER LOW WATER LATE TUESDAY NIGHT...WITH TIDES POSSIBLY REACHING 4 FEET BY EARLY WEDNESDAY MORNING. RAIN CHCS WILL CONTINUE INTO THE WEEKEND...BUT SLOWLY DIMINISH...AS THE UPR LOW CONTINUES TO MEANDER OVER THE AREA...WITH MOST MODELS SHOWING THE LOW FINALLY LIFTING NE BY SUNDAY. && .MARINE... A TIGHT PRES GRADIENT BETWEEN HIGH PRES CNTRD OFF THE SE STATES AND LOW PRES DEEPENING OVER TX WILL BRING STRONG SLY WINDS AND BUILDING SEAS THROUGH AT LEAST WEDNESDAY. FREQUENT WIND GUSTS TO AROUND 40 KT WILL BE POSSIBLE...ESPECIALLY FROM TUESDAY NIGHT INTO WEDNESDAY. SMALL CRAFT ADVISORIES ARE IN EFFECT AND A GALE WATCH HAS ALSO BEEN ISSUED. IN ADDITION TO THE STRONG WINDS AND ROUGH SEAS...OCNL PERIODS OF SHOWERS AND TSTMS CAN BE EXPECTED AS A STRONG UPR LVL DISTURBANCE BECOMES STALLED OVER NRN MEXICO. WINDS AND SEAS WILL GRADUALLY BEGIN TO DIMINISH FROM WEST TO EAST THURSDAY...WITH WINDS BECOMING MORE WEST TO SOUTHWEST LATE IN THE WEEK. && .PRELIMINARY POINT TEMPS/POPS... AEX 63 76 66 74 / 20 90 90 90 LCH 65 77 67 74 / 10 100 90 90 LFT 65 77 69 74 / 10 70 70 80 BPT 66 78 68 75 / 20 100 90 90 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH LATE WEDNESDAY NIGHT FOR LAZ027-028-030-031-041-073. COASTAL FLOOD WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY EVENING FOR LAZ052>055-073-074. TX...FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH LATE WEDNESDAY NIGHT FOR TXZ180-201-215-216-259>262. COASTAL FLOOD WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY EVENING FOR TXZ215. WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR TXZ215-216. GM...GALE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY AFTERNOON FOR GMZ450-452-455-470-472-475. SMALL CRAFT ADVISORY UNTIL 6 PM CST TUESDAY FOR GMZ470-472-475. SMALL CRAFT EXERCISE CAUTION UNTIL 6 PM CST THIS EVENING FOR GMZ430-470-472-475. SMALL CRAFT ADVISORY FROM 6 AM TUESDAY TO 6 PM CST WEDNESDAY FOR GMZ430-432-435. SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM CST TUESDAY FOR GMZ450- 452-455. SMALL CRAFT EXERCISE CAUTION THROUGH LATE TONIGHT FOR GMZ450-452- 455. && $$ PUBLIC...24