The Great South Carolina Flood - Or Good Luck Clemson

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Invest in a boat and try to collect two of every animal bros.

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MESOSCALE PRECIPITATION DISCUSSION 0546 NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1011 AM EDT SAT OCT 03 2015 AREAS AFFECTED...WESTERN NORTH CAROLINA...SOUTH CAROLINA CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY VALID 031400Z - 032000Z SUMMARY...SIGNIFICANT AND LIFE-THREATENING FLASH FLOODING IS EXPECTED THROUGH THE AFTERNOON ACROSS A LARGE PORTION OF SOUTH CAROLINA AND WESTERN NORTH CAROLINA. DISCUSSION...THE SITUATION CONTINUES TO BE LOCALLY VERY SERIOUS ACROSS PORTIONS OF WESTERN NORTH CAROLINA...AND ESPECIALLY THE UPSTATE OF SOUTH CAROLINA AND EXTENDING DOWN TO COASTAL COMMUNITIES INCLUDING METROPOLITAN CHARLESTON. A PERSISTENT AND DEEP TROPICAL MOISTURE PLUME INVOLVING MOISTURE FROM HURRICANE JOAQUIN NORTHEAST OF THE BAHAMAS CONTINUES TO BE CHANNELED NORTHWESTWARD IN OFF THE ATLANTIC OCEAN...AND INLAND ACROSS THE SOUTHEAST COASTAL PLAIN AND INTO THE SOUTHERN APPALACHIANS. THIS IS BEING FOCUSED AROUND THE NORTHEAST FLANK OF A DEEP CLOSED LOW OVER SOUTHEAST ALABAMA AND WITHIN A STRONGLY DIVERGENT FLOW PATTERN ALOFT THAT IS BEING FACILITATED BY ROBUST 250 MB RIGHT-ENTRANCE REGION JET DYNAMICS. WHILE THE STRONGEST INSTABILITY CONTINUES TO BE FOCUSED OFFSHORE THE SOUTHEAST COASTLINE NEAR A FRONTAL ZONE...THE STRONG JET DYNAMICS ALOFT COUPLED WITH A VERY MOIST SOUTHEASTERLY LOW LEVEL JET OF 40 KTS OVER THE FRONT IS ALLOWING FOR A PERSISTENT BAND OF HEAVY RAIN WITH SOME EMBEDDED THUNDERSTORMS. PWATS AS PER GOES-SOUNDER AND GPS-DERIVED DATA IS PEAKING AROUND 2.4 INCHES ACROSS THE SOUTH CAROLINA COASTAL PLAIN...AND THIS IS FOSTERING INTENSE RAINFALL RATES IN SOME OF THE STRONGER CONVECTIVE ELEMENTS TO REACH 1.5 TO 2 INCHES/HR. ON THE LARGER SCALE...THE RAINFALL RATES HAVE TENDED TO BE CLOSER TO 1 INCH/HR OR LESS...BUT THE PERSISTENCE OF THE RAINFALL BAND IS LEADING TO VERY SIGNIFICANT RAINFALL TOTALS FOR THE EVENT...AND THIS WILL CONTINUE THROUGH MID-AFTERNOON. THE HIRES AND GLOBAL MODEL GUIDANCE IS BASICALLY UNANIMOUS IN DEPICTING HIGH IMPACT RAINFALL TOTALS THAT WILL LIKELY LEAD TO LOCALLY CATASTROPHIC AND LIFE-THREATENING FLASH FLOODING AND RUNOFF PROBLEMS. EXPECT ADDITIONAL TOTALS THROUGH MID-AFTERNOON TO BE ON THE ORDER OF 3 TO 5 INCHES...WITH ISOLATED HEAVIER AMOUNTS. THIS WILL RESULT IN STORM TOTALS FOR SOME AREAS...ESPECIALLY IN CENTRAL AND SOUTHEAST SOUTH CAROLINA TO ALREADY EXCEED 12 INCHES...WITH MORE RAIN EXPECTED WELL BEYOND THIS PERIOD. THE GUIDANCE INDICATES A GRADUAL SOUTHWESTWARD PIVOTING OF THE DEEP MOISTURE PLUME/RAINFALL AXIS THIS AFTERNOON WHICH WILL INCREASE THE RAINFALL AND FLASH FLOODING CONCERNS FOR THE UPSTATE AREAS OF SOUTH CAROLINA AND ALSO SOUTHWEST NORTH CAROLINA WHERE VERY STRONG UPSLOPE FLOW IS BEING FORECAST BY THE MODELS. IN FACT...THE 00Z GFS PEGGED THIS REGION TO SEE 850MB/700MB MOISTURE FLUX ANOMALIES IN EXCESS OF 5 STANDARD DEVIATIONS ABOVE NORMAL AT 18Z. THUS...EXPECT SIGNIFICANT RAINS TO DEVELOP AND OVERSPREAD THIS REGION OVER THE NEXT SEVERAL HOURS.

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