Severe Weather Climatology for NWS Wilmington, NC 1991-2021

Severe Weather Climatology for NWS Wilmington, NC

Between 1991 and 2021 there were 5,265 reports of severe weather across the area covered by the National Weather Service forecast office in Wilmington, NC.  Reports of tornadoes, large hail, damaging thunderstorm winds, and freshwater flooding were evaluated for this study across the following counties:

North Carolina: Bladen, Brunswick, Columbus, New Hanover, Pender, Robeson
South Carolina: Darlington, Dillon, Florence, Georgetown, Horry, Marion, Marlboro, Williamsburg

Over this time period severe weather was directly responsible for 412 injuries, 35 fatalities, and property damage (inflation-adjusted to 2021 dollars) totaling over $388 million.

Although records of severe weather extend back to 1950, a more recent period was selected for this study given limited records for non-fatal severe weather events prior to the 1990s.  This study did not evaluate damage from saltwater flooding or from winds caused by tropical storms and hurricanes. 

Browse through the tabs above for specific details.

Data Sources:

National Centers for Environmental Information (NCEI) Storm Data:  https://www.ncdc.noaa.gov/stormevents

Storm Prediction Center, U.S. Tornadoes:  https://www.spc.noaa.gov/wcm

TORNADOES 1991-2021

Number of reported tornadoes: 267 (5% of all severe weather reports)
Total damage in inflation-adjusted 2021 dollars:  $97,382,655 (25% of all severe weather damage)
Injuries:  333 (81% of all severe weather injuries)
Fatalities: 20 (57% of all severe weather fatalities)

TOTAL NUMBER OF TORNADOES BY COUNTY, 1991-2021

Tornadoes that have affected southeastern North Carolina and northeastern South Carolina can be sorted into three broad categories.

• Tornadoes not associated with tropical cyclones. "Regular" tornadoes peak in occurrence during spring (March through May) with a secondary peak in November.  There were 169 of these tornadoes reported between 1991 and 2021 across the area served by NWS Wilmington, NC.
• Tropical cyclone tornadoes. These are tornadoes that develop within a landfalling tropical cyclone.  These have occurred as early as June and as late as October, but most develop during September in the climatological peak in Atlantic tropical cyclone activity.  There were 92 confirmed tropical cyclone tornadoes across this area between 1991 and 2021.
• Fair weather waterspouts.  Exclusively a summer phenomenon, fair weather waterspouts are typically weak and dissipate within moments of reaching land as tornadoes.  Although numerous waterspouts likely occur across the coastal and offshore waters each summer, only six were confirmed to have moved onshore between 1991 and 2021.

TOTAL NUMBER OF TORNADOES BY MONTH, 1991-2021

Some significant tornado outbreaks on record for southeastern North Carolina and northeastern South Carolina include:

• March 28, 1984: Twenty-two tornadoes touched down across the central and eastern portions of the Carolinas with 57 fatalities and over 1,200 injuries reported.  Multiple tornadoes produced F3 and F4 damage. Near Maxton, NC the damage path was surveyed at 2.5 miles wide.
• November 5, 1995: Twelve tornadoes touched down across northeastern South Carolina into Columbus County, NC.  One tornado was found to have produced F4 damage in Marion County, SC.  A total of 140 injuries occurred during this outbreak across the NWS Wilmington forecast area including 122 in Columbus County alone.
• November 16, 2006: An early morning F3 tornado struck Riegelwood, NC, killing 8 people and injuring 20.
• April 16, 2011: Eleven tornadoes struck the area covered by the NWS office in Wilmington, killing 4 people and injuring 16.  This was part of an historic outbreak of tornadoes that spanned the southern U.S. between April 14 and April 16, 2011.
• September 15-16, 2018: Hurricane Florence produced 17 tornado touchdowns across the NWS Wilmington, NC forecast area.
• September 5, 2019: Hurricane Dorian produced 17 confirmed tornado touchdowns.
• February 15, 2021: An EF3 tornado struck the Ocean Ridge community in western Brunswick County, killing 3 and injuring 10.  The tornado remained on the ground for 22 miles.

TOTAL NUMBER OF TORNADOES BY TIME OF DAY, 1991-2021

Tornadoes not associated with tropical cyclones showed a strong association with afternoon and evening occurrence, mainly between 2 p.m. and 7 p.m. local standard time.  Tornadoes associated with tropical cyclones showed little diurnal preference and were actually the most numerous tornado variety during the pre-dawn morning hours.  Landfalling fair weather waterspouts most often occurred during late mornings between 8 a.m. and 11 a.m. local time.

TORNADO INTENSITY, 1991-2021

Since few weather stations are designed to survive the powerful winds of a tornado, tornado intensity is estimated based on the degree of damage left behind.  The Enhanced Fujita Scale, an improvement on the original Fujita Scale from 1971, uses 28 damage indicators to estimate a tornado's wind speeds.

Over half (55 percent) of all recorded tornadoes across southeastern North Carolina and northeastern South Carolina were weak, F0/EF0, with wind speeds of 85 mph or less.  Tornadoes of F1/EF1 intensity made up an additional 36 percent of events.  Only 9 percent for tornadoes were strong: F2/EF2 intensity or stronger.

A very small number, around one percent, of local tornadoes were F3/EF3 or stronger with wind speeds in excess of 136 mph. 

There was no significant difference in intensity noted between the average tropical cyclone tornado versus non-tropical tornado.  Observed landfalling fair weather waterspouts were all weak with wind speeds less than 85 mph. 

Only one tornado during this study period was rated F4.  It occurred in Marion County, SC on November 5, 1995.  Prior to 1991, a significant tornado outbreak on March 28, 1984 produced multiple F3 and F4 tornadoes across the Carolinas and is the largest and most destructive severe weather outbreak in local history.

TORNADO INTENSITY BY COUNTY, 1991-2021

Tornadoes have occurred in every county covered by NWS Wilmington, NC.  Even prior to 1991, there has never been an F5/EF5 tornado confirmed in either North or South Carolina. 

Strong tornadoes (F3/EF3 or stronger) have been recorded near the coast (Brunswick County in 2021) as well as inland (Marion County in November 1995, and Columbus County in November 2006.)

TORNADO TYPE BY COUNTY, 1991-2021

Tornadoes from both tropical and non-tropical weather systems have occurred in every county across the NWS Wilmington, NC forecast area, however fair weather waterspouts were limited to coastal counties only.

TORNADO TYPE BY COUNTY, NORMALIZED BY AREA

Since counties vary greatly in size, a better metric to gauge tornado frequency may be the number of tornadoes per unit area.  The table and chart below show county tornado totals normalized to the number of events reported per 100 square miles over the period 1991 to 2021.

The relatively large normalized frequency of tornadoes observed in New Hanover County, NC could reflect the high population density of the county and an assumed high reporting efficiency even for weak tornadoes.  The relatively low tornado frequency calculated for some inland counties like Marlboro and Marion, SC, may reflect low population density and an assumed low reporting efficiency for tornadoes there.

Reporting efficiency is a hypothetical ratio of reported tornadoes to the number of tornadoes that actually occurred -- a value that realistically cannot be known.  A short-track, weak tornado occurring in a rural area has a relatively low chance to be observed and reported; however, a similar event occurring within a densely populated area has a considerably higher chance of being reported.

TOTAL TORNADO INJURIES AND FATALITIES, 1991-2021

Non-tropical tornadoes were responsible for over 87 percent of tornado-related injuries and fatalities across the NWS Wilmington, NC forecast area between 1991 and 2021.  Tornadoes associated with tropical cyclones were responsible for the remainder of tornado-related injuries, all occurring during the peak of the Atlantic Hurricane Season from August through October.  Within the time period covered by this study, fair weather waterspouts caused no injuries or fatalities.

There was a single, large severe weather outbreak on November 7, 1995 when a series of 12 tornadoes injured 140 people across northeastern South Carolina into Columbus County, NC.  Even if we were to assume this one November event was an outlier, other tornado events during November also have led to numerous injuries and fatalities.  Perhaps surprisingly, November is statistically the most dangerous month of the year for tornado-related injuries and fatalities across this portion of the Carolinas. 

Monthly totals of injuries and fatalities due to tornadoes bear little relationship to raw tornado counts which show pronounced peaks in April (non-tropical tornadoes) and September (tropical tornadoes).

TORNADO INJURIES & FATALITIES BY INTENSITY

Weak tornadoes, rated F0/EF0 and F1/EF1, made up the majority of tornado events in the NWS Wilmington, NC forecast area.  Statistically only 10 percent of these weak tornadoes have resulted in any injuries or fatalities. 

Over half of F2/EF2 tornadoes have produced injuries or fatalities with an average of 11 injuries per tornado noted within the study period.  For violent tornadoes, F3/EF3 and stronger, all recorded events within the study period produced at least one injury or fatality.  Each F3/EF3 and stronger tornado injured or killed an average of 14 people.

TORNADO DAMAGE BY MONTH, 1991-2021

In contrast to injury and fatality statistics, damage amounts correlate fairly well with raw tornado counts per month across the area served by NWS Wilmington, NC. For tornadoes not associated with tropical cyclones, the largest damage amount and the largest number of recorded tornadoes have occurred in the month of April. 

Tornadoes associated with tropical cyclones peak in occurrence and also in recorded damage during the month of September. 

Landfalling fair weather waterspouts have caused only small amounts of property damage.

All monetary damage reports below are in inflation-adjusted 2021 dollars.

TORNADO DAMAGE BY F/EF SCALE CLASSIFICATION

As tornado intensity increases, the capacity for damage, injuries, and fatalities also increases.  Weak tornadoes, F0/EF0 through F1/EF1 intensity, were responsible for slightly over $126,000 in monetary damage per event, on average.  These weak events made up the majority of tornadoes within the NWS Wilmington forecast area.

The average F2/EF2 tornado caused over $2.5 million in property damage. 

For F3/EF3 and stronger tornadoes, the average damage per event was nearly $4.5 million.

TORNADO PATH LENGTH, 1991-2021

Although a small number of tornadoes in the NWS Wilmington, NC forecast area have had observed path lengths in excess of 20 miles, the majority are on the ground for less than one mile.  Path length statistics show a non-standard distribution with a notable difference between the mean and median path length.  Among non-tropical tornadoes, the mean (50th percentile) path length is 0.5 miles while the average is nearly 2 miles. 

For tornadoes associated with tropical cyclones, the mean path length (0.8 miles) is longer than for non-tropical tornadoes likely due to a faster translation speed of the tornado across the ground.  However, there were no tropical tornadoes with path lengths in excess of 10 miles.

All observed fair weather waterspouts had short overland path lengths of one-third of a mile or less.  These circulations quickly dissipate once they move across the rough ground surface.

In the box-and-whisker plot below, the mean path length is indicated by an "x" while the median path length is indicated by the horizontal line bisecting the colored rectangle.  The rectangle encompasses the 25th through 75th percentile of path length observations for each tornado type, while the "whisker" extends another 1.5 times the interquartile length.  Colored dots represent outlier observations near the limits of the observed data.

HAIL (1991-2021)

Number of reported hail events: 1605 (30% of all severe weather reports)
Total damage in inflation-adjusted 2021 dollars:  $59,642,164 (15% of all severe weather damage)
Injuries:  2 (<1% of all severe weather injuries)
Fatalities: 0 (0% of all severe weather fatalities)

TOTAL NUMBER OF HAIL REPORTS BY COUNTY, 1991-2021

Hail forms when raindrops are carried upward by thunderstorm updrafts into cold upper regions of the troposphere and freeze. Hail grows larger by colliding with liquid water drops that freeze onto the hailstone’s surface. Eventually hail falls to the ground when the thunderstorm's updraft can no longer support the weight of the hailstones which can occur if they become too heavy or if the updraft weakens.

Large hail (1.00 inch diameter or larger) occurs only in severe thunderstorms.  These same severe thunderstorms often produce damaging winds, and can produce flooding or tornadoes as well.

TOTAL NUMBER OF HAIL REPORTS BY MONTH, 1991-2021

No fatalities occurred due to hail in the NWS Wilmington, NC forecast area between 1991 and 2021.  Some significant hail events in local history include:

• May 25, 2000:  The largest and most destructive hail event in local history occurred on this date in Florence, SC.  Hail up to 4.50 inches in diameter injured two people and caused over $47 million (inflation-adjusted to 2021 dollars) of property damage.
• May 10, 2011:  During a widespread large hail event across the eastern Carolinas exceptionally large hail (up to 4.50 inches in diameter) fell in Conway and Pamplico, SC
• May 5, 2020:  Many reports of hail up to three inches in diameter fell were received from Hartsville, Clyde, and Dovesville in Darlington County, SC.
• February 24, 2016:  A rare winter large hail event in Robeson County, SC produced hailstones up to three inches in diameter.
• May 3, 1994:  Golf ball size hail fell across Columbus County, NC and caused over $9 million (inflation-adjusted to 2021 dollars) of property damage

RELATIVE HAIL OCCURRENCE BY MONTH, 1991-2021

Small hail has been reported across southeastern North Carolina and northeastern South Carolina in every month of the year except for December.  But from the standpoint of relative occurrence, 36 percent of all area hail reports are from the month of May. 

Even more surprising is that 52 percent of all hail reports 1.75 inches and larger, and 80 percent of all hail reports 2.50 inches or larger in diameter have occurred during the month of May.  May is, by far, the month most likely to see significant impacts from hail across this portion of the Carolinas.

HAIL REPORTS BY TIME OF DAY, 1991-2021

Hail has a strong association with the afternoon and evening hours when solar heating can create atmospheric instability.  This instability is necessary to fuel the thunderstorm updrafts that create hail.  Hail is rare after 10:00 pm and during the morning hours.

HAIL OCCURRENCE BY COUNTY, 1991-2021

Hail has fallen in virtually every community within the NWS Wilmington, NC forecast area.  The largest number of reports of hail of all sizes originated from Horry County, SC. 

Giant hail, 2.50 inches or larger in diameter is rare but was most likely to occur across inland areas of northeastern South Carolina. No hail reports of this size occurred during this study period across coastal southeastern North Carolina.

HAIL OCCURRENCE BY COUNTY NORMALIZED BY AREA

Since counties vary greatly in size, a better metric to gauge hail frequency may be the number of hail reports per unit area.  The table and chart below shows county hail totals normalized by the number of events reported per 100 square miles over the period 1991 to 2021.

The relatively large normalized frequency of hail observed in New Hanover County, NC could reflect the high population density of the county and an assumed high reporting efficiency even for small hail.  The relatively hail frequency calculated for some inland counties like Dillon, Marlboro, and Marion, SC, may reflect low population density and an assumed low reporting efficiency for hail there.

Reporting efficiency is a hypothetical ratio of reported hail events to the number of hail events that actually occurred -- a value that realistically cannot be known.  Hail causing little or no damage across a rural area has a relatively low chance to be observed and reported; however, a similar event occurring within a densely populated area has a considerably higher chance of being reported.

HAIL DAMAGE BY MONTH, 1991-2021

The vast majority of all reported property damage from hail across southeastern North Carolina and northeastern South Carolina between 1991 and 2021 has occurred during the month of May.  The majority of that damage occurred during a single severe thunderstorm that struck the Florence, SC area on May 25, 2000 which caused over $47 million in damage as measured in inflation-adjusted 2021 dollars.  Hail falling from other severe thunderstorms during the month of May has damaged an additional $10 million dollars of property.

Besides May, June is the only other month to have accumulated over $1 million in inflation-adjusted 2021 dollars of hail damage across southeastern North Carolina and northeastern South Carolina.

DAMAGING WINDS (1991-2021)

Number of reported damaging wind events: 2627 (50% of all severe weather reports)
Total damage in inflation-adjusted 2021 dollars:  $46,950,381 (12% of all severe weather damage)
Injuries:  73 (18% of all severe weather injuries)
Fatalities: 0 (0% of all severe weather fatalities)

DAMAGING WIND REPORTS BY COUNTY, 1991-2021

Although damaging winds can occur from a variety of weather events including tropical cyclones, Nor'easters, and strong fronts, this study focused on winds produced by thunderstorms.  Note that straight-line wind events are counted separately from tornadoes.

Prior to 1996 many NWS storm damage reports did not include wind speed estimates or measurements.  This may skew statistics slightly for damage without wind speeds of 58 mph or greater.

Some of the more notable instances of local thunderstorm wind damage include:

• August 10, 2007:  Thunderstorm winds estimated as high as 95 mph injured seven people and damaged $1.31 million (in inflation-adjusted 2021 dollars) in property in the Green Sea community of Horry County, SC.
• March 15, 2008:  Thunderstorm winds as high as 83 mph injured seven people and damaged over $2.5 million (in inflation-adjusted 2021 dollars) in property in Ashton, Pender County, NC.  Numerous pine trees were blown down or snapped along a path about 100 yards wide and 300 yards long. Five mobile homes were damaged by downed trees in the Interstate Mobile Home Park and adjacent Cedar Grove Mobile Home Park.
• May 3, 1994:  Severe thunderstorm winds caused over $9 million (in inflation-adjusted 2021 dollars) in property across Columbus County, NC.  One child, one teenager, and two adults were injured. Eleven businesses and multiple homes were damaged, and numerous power lines were downed. Several liquid propane gas tanks were damaged.
• May 20, 2005:  Severe thunderstorm winds in Conway, SC damaged over $1.6 million (in inflation-adjusted 2021 dollars) of property.  Winds caused two air conditioning units to fall through the roof of the Loris Community Hospital. Nearby trees, vehicles, and nearby buildings were also damaged, including the Loris town jail.
• May 11, 2009:  An NWS storm survey found evidence for straight-line winds as high as 125 mph in the Allenton community of Robeson County, NC. Numerous trees and power lines were blown down and there was considerable structural damage. Numerous large trees were snapped off or uprooted along NC Highway 72 and significant structural damage occurred to approximately 8 homes on Sadie Drive. One of these homes was completely destroyed and another lost its entire roof. Several sheds and outbuildings were destroyed in this area. One adult woman suffered broken bones. The damage had a maximum path width of 350 yards and a path length of 2.25 miles.
• May 31, 2003:  In Wilmington, NC, an NWS storm survey concluded a microburst produced estimated 100 mph wind gusts and extensively damaged many homes in the Brittany Woods subdivision. Nearly 100 homes sustained damage. Half a dozen homes were more seriously damaged with blown-in garage doors, allowing the wind to blow portions of walls and/or roofs away.

   

DAMAGING WIND REPORTS BY MONTH, 1991-2021

DAMAGING WIND REPORTS BY TIME OF DAY, 1991-2021

Damaging winds associated with thunderstorms peaked in occurrence between 3:00 pm and 7:00 pm local standard time and became more uncommon during the overnight hours.  This mirrored the afternoon and early evening peak in thunderstorm occurrence driven by solar heating and subsequent destabilization of the atmosphere.

DAMAGING WIND REPORTS BY COUNTY, 1991-2021

Severe thunderstorms have produced damaging winds across all portions of the eastern Carolinas. 

DAMAGING WIND REPORTS BY COUNTY, NORMALIZED BY AREA

Since counties vary greatly in size, a better metric to gauge damaging wind frequency may be the number of reports per unit area.  The chart and table below shows county damaging wind totals normalized to the number of events reported per 100 square miles over the period 1991 to 2021.

The relatively large normalized frequency of damaging winds observed in New Hanover County, NC could reflect the high population density of the county and an assumed high reporting efficiency for wind damage.

Reporting efficiency is a hypothetical ratio of reported damaging wind events to the number of damaging wind events that actually occurred -- a value that realistically cannot be known.  Damaging wind causing little or no property damage across a rural area has a relatively low chance to be observed and reported; however, a similar event occurring within a densely populated area has a considerably higher chance of being reported.

DAMAGING WIND INJURIES, 1991-2021

Winds from severe thunderstorms have caused 73 reported injuries across the NWS Wilmington, NC forecast area between 1991 and 2021.  With the exception of two reported injuries in February and two more in September, all thunderstorm wind-related injuries have occurred during the spring and summer months of March through August.

During the period covered by this study, no fatalities were reported due to thunderstorm winds.

DAMAGING WIND INJURIES BY COUNTY, NORMALIZED BY POPULATION

The largest number of injuries due to thunderstorm winds over the study period occurred in Horry County with 19 reported during the study period.  This was followed by Darlington County with nine wind-related injuries. 

But when normalized by county population, Bladen County, NC was shown to have the highest per capita number of injuries due to thunderstorm winds at 18.3 injuries per 100,000 people.  This is over three times the average of 5.2 injuries per 100,000 population across the NWS Wilmington, NC forecast area during the period 1991 to 2021

TOTAL WIND DAMAGE BY MONTH, 1991-2021

Across the NWS Wilmington, NC forecast area, property damage due to severe thunderstorm winds has occurred in all months of the year.  The $19 million damage total for May is over 41 percent of total reported wind damage across the entire 1991 to 2021 period.  Thunderstorm wind damage during the cool season (October through February) has relatively small cumulative damage totals.

FLOODS (1996-2021)

Number of reported flood events: 766 (15% of all severe weather reports)
Total damage in inflation-adjusted 2021 dollars:  $184,578,370 (48% of all severe weather damage)
Injuries:  4 (1% of all severe weather injuries)
Fatalities: 15 (43% of all severe weather fatalities)

TOTAL NUMBER OF FLOOD EVENTS BY COUNTY, 1996-2021

Freshwater flooding across the eastern Carolinas comes from three primary sources:

• Flooding from sustained periods of rainfall.  This can happen at any time of the year as long as rainfall sufficient to overwhelm drainage systems has occurred.  Even moderate rainfall rates, if sustained for a long enough period, can lead to flooding.
• Flash flooding from heavy rain in thunderstorms.  Thunderstorms primarily develop during the warmer half of the year, and flooding from thunderstorms peaks in occurrence during the summer.  When rainfall rates exceed three or four inches per hour, flash flooding can occur.
• Flooding from tropical cyclones.  Tropical cyclones almost exclusively occur during the summer and fall months and are capable of sustained, extreme rainfall rates and exceptional flooding.  The majority of local injuries or fatalities due to freshwater flooding have occurred in tropical cyclones.

Flash flooding is generally described as significant flooding that occurs rapidly due to ongoing heavy rainfall.  Operationally and for record keeping purposes, "flash flooding" versus "flooding" has been classified differently over the years this study covers.  For this reason, this study considered both types of flooding together rather than separately, with events sorted by the causative event: tropical cyclone vs. all others.

Systematic cataloging of flood events in NCEI's Storm Data publication did not begin until 1996.

TOTAL NUMBER OF FLOOD EVENTS BY MONTH, 1996-2021

Flooding has affected all portions of the eastern Carolinas and in every month of the year.  Flooding is least likely to occur in winter and is most likely to occur during the summer and through the first half of the fall due to thunderstorms and tropical cyclones.

Some of the most significant flooding events in local history include:

• Hurricane Florence: September 15, 2018.  Florence was a slow-moving category one hurricane that made landfall at Wrightsville Beach, NC and produced record-breaking rainfall across eastern North Carolina and a portion of northeastern South Carolina.  Over 30 inches of rain were measured in a few North Carolina locations, exceeding the highest single-storm rainfall amounts ever seen in this portion of the state.  A station in Loris, SC recorded 23.63 inches of rain, setting a new state tropical cyclone rainfall record for the state of South Carolina.  In North Carolina an estimated 74,563 structures were flooded and 5,214 people were reportedly rescued from flooding.  South Carolina Emergency Management reported 9 fatalities across the state; $607 million damage; 11,386 homes with moderate or major damage; 455,000 people evacuated, and 11 dams breached or failed.
• Hurricane Matthew: October 4, 2015.  Twelve to eighteen inches of rain fell over large portions of interior South and North Carolina.  This occurred at the end of a wet period which had seen six to ten inches of rain dropped by Tropical Storm Hermine. Deadly flash flooding occurred, and was followed by extensive river flooding that took weeks to subside.  Matthew was directly responsible for 25 deaths in North Carolina and four in South Carolina, all but one due to flooding.  Damage in the United States was estimated by the National Center for Environmental Information (NCEI) at $10.3 billion (in 2015 dollars.)
• Hurricane Floyd:  September 15, 1999.  Widespread rainfall amounts of 10 to 20 inches led to catastrophic and then-unprecedented flooding across sections of eastern North and South Carolina northward across the Mid-Atlantic states.  Floyd’s death toll reached 36 in North Carolina and 57 across the United States as a whole, with total damage estimates near $6.5 billion.  Millions of farm animals were drowned and upward of 80,000 structures were damaged or destroyed.  Flooding closed a 100-mile segment of Interstate 95 in northeastern North Carolina into a portion of Virginia.  North Carolina Governor Jim Hunt was quoted: “We have seen the worst flooding in anybody’s memory.” 
• October 4, 2015.  Historic flooding occurred in early October as a persistent plume of tropical moisture dumped never-before-seen amounts of rain across eastern South Carolina.  Moisture stripped from Hurricane Joaquin, located well offshore, may have contributed to the rainfall totals.  The heaviest rainfall occurred from October 2nd through 4th with anywhere from 2 to 10 inches of rain falling each day.  Storm-total rainfall amounts were 20 to 24 inches near Georgetown and Kingstree, SC, with even higher totals in the Charleston/Mount Pleasant, SC area.  According to an NWS Exceedance Probability Analysis on this event, heavy rainfall like this can be expected to occur less than once every thousand years across eastern South Carolina.
• March 20, 2001:  Heavy rain along the Carolina coast led to flash flooding. In Horry County, there was major roadway flooding in Myrtle Beach. Two fatalities were reported in South Carolina: one each in Surfside Beach and Georgetown.  Flash flooding occurred in Wilmington, NC along Market Street and numerous other roadways. Highway 53 in Pender County was under water.

FLOODING EVENTS BY TIME OF DAY, 1996-2021

Flooding not associated with tropical cyclones shows a daily peak in occurrence between 3:00 pm and 7:00 pm, mirroring the late afternoon and early evening peak in summer thunderstorms.  Flooding is least likely to occur during the early morning hours before 6:00 am.  

Flooding associated with tropical cyclones shows less dependence on time of day but still occurs most often during the daylight hours between 9:00 am and 3:00 pm.

FLOOD EVENTS BY COUNTY, 1996-2021

Flooding from both tropical and non-tropical causes has affected every county in the NWS Wilmington, NC forecast area.  The largest number of individual flood events has been reported from New Hanover County, NC, followed by Brunswick and Pender counties.  The coastal Cape Fear counties of southeastern North Carolina have the highest average annual precipitation totals of the NWS Wilmington, NC forecast area, and also contain the populous Wilmington metro area.

Across northeastern South Carolina, the largest number of flood reports has come from Horry County, followed by Georgetown and Florence counties.  

FLOODING INJURIES AND FATALITIES, 1996-2021

Tropical cyclone-related flooding made up 30 percent of all flooding reports across the NWS Wilmington, NC forecast area between 1996 and 2021, but was responsible for the majority of injuries and fatalities that occurred.

FLOODING INJURIES AND FATALITIES BY COUNTY, 1996-2021

FLOOD DAMAGE, 1996-2021

The vast majority of reported flood damage within the NWS Wilmington, NC forecast area has occurred during hurricanes in September and October.  Hurricanes Florence (2018), Matthew (2016), and Floyd (1999) produced widespread and exceptional flood damage across many portions of the Carolinas.

When considered together with the October 2015 floods, these four events make up the vast majority of the flood impacts this area received over the period 1996 to 2021.