South Carolina s Historic Rains and Flooding October 2015 // October Hope Mizzell, Ph.D. SC State Climatologist

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1 South Carolina s Historic Rains and Flooding October 2015 // October 2016 Hope Mizzell, Ph.D. SC State Climatologist

2 NOAA Forecasts October 2015 Issued Oct 1, 5:45 AM Issued Oct 2, 5:45 AM Issued Oct 3, 7:55 AM

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4 Infrared satellite from the morning of Oct. 3 shows an intense area of rainfall being funneled into SC. Hurricane Joaquin peaked as a Category 4 hurricane with maximum sustained winds of 155 mph at that time. NASA

5 NOAA Water Vapor with Overlay of Parameters Contributing to the Heavy Rain

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8 Precipitation (in) NOAA ATLAS 14 POINT PRECIPITATION FREQUENCY ESTIMATES Preliminary Analysis for Sumter, SC: Sep 28-Oct 6, Sumter, South Carolina: Sept Oct. 6 Average Return Interval 25 Years 50 Years Years 200 Years Years 1000 Years 5 Precip Total (in) 0 24-hour 2-day 3-day 4-day 7-day 10-day 30-day Based on Greatest 24-hr and Consecutive (2-day, 3-day, 4-day, 7-day) interval days Based on NOAA Atlas 14 Precipitation Frequency Estimates

9 Precipitation (inches) NOAA ATLAS 14 POINT PRECIPITATION FREQUENCY ESTIMATES Preliminary Analysis for Columbia, AP: Sep 28-Oct 6, Columbia Metro Airport: Sept Oct Average Return Interval 25 Years 50 Years 100 Years 200 Years 500 Years 1000 years 0 24-hr 2-day 3-day 43-day 7-day 10-day 30-day Greatest 24-hr and Consecutive (2-day, 3-day, 4-day) interval days Based on NOAA Atlas 14 Point Precipitation Frequency Estimates

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11 Rainfall (inches) 25 Ft. Jackson Accumulated Hourly Rainfall Oct. 2 Oct. 3 Oct. 4 Oct. 5

12 Gills Creek Watershed, Richland County Gills Creek Watershed is among the largest impaired urban watersheds in SC, and contains over 70 miles of streams and lakes, and 47,000 acres of land. The watershed is included in the cities of Columbia, Cayce, Forest Acres, and Arcadia Lakes; Richland County, and the US Army's Fort Jackson. The population is 140,000.

13 Before Before After After

14 October 4, 2015 Skii Lane Cary Lake Dam Photo by Wes Tyler

15 October 4, 2015 Trenholm Road, North Forest Drive Photo by Wes Tyler October 4, 2015 Quail Lane Lake Katherine Photo by Wes Tyler

16 Before After

17 Selected USGS Stream Gages Enoree River at Whitmire 18,400 cfs peak on 10/5 50 year flow Lynches River at Effingham 17,000 cfs peak on 10/6 50 year flow Congaree River at Columbia 185,000 cfs peak on 10/4 10 year flow Black River at Kingstree 83,700 cfs peak on 10/ year flow Edisto near Ghivans 25,600 cfs peak on 10/9 50 year flow

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19 Hartwell, Russell, and Thurmond No change Reservoirs Lake Wylie No change Lake Wateree 21,300 cfs Average is 3,000 cfs Lake Murray 56,000 cfs. Average is 2,000 cfs Lake Marion + Moultrie 100,000 cfs (estimate, some data missing) Average is 6,600 cfs

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21 Interactive Journal of the Historic Rain and Flooding

22 Hurricane Matthew

23 NOAA Forecasts October 2016 Issued Oct 5, 8:00 AM Issued Oct 6, 4:33 AM Issued Issued Oct Oct 7, 4:33 7 4:33 AM AM

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25 Hurricane Matthew First SC hurricane landfall since Hurricane Charley and Gaston came ashore in Made landfall on SC coast, near McClellanville, on Oct. 8th, 2016, 10:45 AM EDT, as a Category 1 hurricane with 75 mph winds.

26 Hurricane Matthew Developed into a rare 160 mph Category 5 hurricane in central Caribbean during first week of October. Decimated portions of Haiti and Bahamas with torrential rains and 145 mph winds. In the days just prior to landfall Matthew battered the east coast of Florida and Georgia

27 Impacts to South Carolina Matthew triggered the evacuation of the entire SC coast and the first successful complete lane reversal of Interstate 26 from Charleston to Columbia. 77 emergency shelters were opened Severe beach erosion and hurricane force gusts downed thousands of trees along coast and well inland. Produced inches of rain from Savannah through Florence and into a wide area of eastern NC. Heavy rain forced rivers in eastern SC and NC above major flood stage.

28 A federal major disaster declaration for 26 SC counties was issued Oct. 11 th in response to: 355,000 displaced citizens homes damaged or destroyed 25 breached dams 866,000 household power outages Pervasive flooding along the Great Pee Dee, Little Pee Dee, Waccamaw, Black and Lynches Rivers.

29 Wind Gusts Maximum sustained winds were 165 mph with gusts to 190 mph late on Sep. 30 th in central Caribbean. First Atlantic Category 5 hurricane since Hurricane Felix in Weakened significantly prior to landfall in SC. Hurricane force wind gusts were observed along SC coast with the highest gust, 103 mph, recorded by an elevated instrument tower in Winyah Bay.

30 Chronological Narrative of Hurricane Matthew Friday Oct 7 7:00 am: Outer-most rain bands approached Beaufort County 10:00 am: US Coast Guard Pilot closed Charleston Harbor to all traffic 8:50 pm: 63 mph winds in heavy rain over Hilton Head Island 11:00 pm: Center of circulation 40 miles SE of Hilton Head and moving N 12 mph Saturday Oct 8 4:00 am: Winds over Hilton Head increased to hurricane force (74 mph) with steep pressure falls Blowing heavy rain accumulated to 9.83 inches at Limehouse Onshore winds forced water in Charleston Harbor to a height of ft. (highest since Hurricane Hugo in 1989) 6:50 am: 88 mph winds roared at Hilton Head Island AP. Not since Hurr. Gracie in Sep 1959 had these conditions been witnessed by state s southern-most islands Wind-driven breakers dismantled lower floors of Edisto Island s low-elevation beachfront cottages and moved an estimated 4 ft. of beach sand on to Palmetto Boulevard and to the second row

31 Chronological Narrative of Hurricane Matthew Saturday Oct 8 6:46 am: Short path/narrow tornado (EF0) formed N Myrtle Beach tracked through Surf Golf Beach Club 10:06 am: 80 mph winds peaked at Ft. Sumter Range Light Large watercraft, torn from moorings, drifting in marsh at Isle of Palms 10:45 am: Hurr. Matthew (Cat 1) made landfall at Cape Romain Nat. Wildlife Refuge Torrential rains at Galivant s Ferry were up to inches. 12:00 pm: Giant waves began breaking apart Springmaid Pier at Myrtle Beach 67 mph High winds at Florence with downed trees reported as everywhere 4:24 pm: 103 mph wind gust Georgetown Winyah Bay Range Light. 5:00 pm: 87 mph wind gust Murrells Inlet Electrical fire in Cherry Grove, rapidly consumed vacation complex. Fanned by hurricane force winds, flames spread into at least four more beachfront properties 11:59 pm: Earthen dam failure at Wallace in Marlboro County blamed for a train engine and four-car derailment. Calendar-day rainfall at Florence of inches, its greatest 1-day rainfall in over 120 yrs of recordkeeping and bested record rains of 1916 Bulls Bay Hurricane and Hazel in 1954.

32 Chronological Narrative of Hurricane Matthew Sunday October 9 Mullins reported an event rainfall total of inches. Lumber, Little Pee Dee & Waccamaw rivers swelled to Major Flood and rising. Wednesday October 12 Little Pee Dee River at Galivant s Ferry rose to a record crest of ft. Town of Nichols submerged under adjacent Lumber River floodway Non-elevated property along Waccamaw River near and below Conway had to be abandoned. Tuesday, October 18 5:15 am: Waccamaw River near Conway reached ft November 2 After 25 days at or above flood stage (11 feet), Waccamaw River near Conway subsided to below flood stage.

33 Highest rainfall recorded at an SC station was inches at Dillon NWS site. Most wide-spread heavy rain fell in the Pee Dee Basin and on into NC, where major flooding occurred.

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35 Highest Precipitation in a 24 hour period at each location. Maximum precipitation time window for one location may be different from the time window at another location. *Precipitation grids generated by MetStat, Inc for the SC State Climate Office

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37 2015 event lasted much longer (4 to 7 consecutive days of rainfall), which accumulated greater totals of rainfall compared to rain associated with Matthew, which lasted only 24 to 36 hours in most places.

38 River and Stream Gages THREE gages set new record peaks and THREE others were within the top three peak annual flows. With widespread heavy rain in Pee Dee Basin of SC and NC, major rivers experienced major flooding, including the Pee Dee, Little Pee Dee, Waccamaw Rivers. The Lumber River flooded towns in both Carolinas, including the town of Nichols, SC. Data Source: Preliminary peak stage and streamflow data at selected streamgaging stations in North Carolina and South Carolina for flooding following Hurricane Matthew, October

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40 Interactive Journal of Hurricane Matthew, October 8,