Severe Thunderstorms with extremely large hail in Florence, SC: May 25, 2000

Severe thunderstorms developed across southeast North Carolina and northeast South Carolina, producing hail up to 4.5 inches in diameter and damaging winds from mid afternoon into the evening. A total of 23 severe thunderstorm and 3 tornado warnings were issued for 11 counties in NWS Wilmington's county warning area.

The thunderstorms developed during the afternoon along an outflow boundary that had migrated into the area from storms that moved across north central and northeast North Carolina earlier in the day. The development of severe storms was aided by an upper level low system that moved directly over the area. The main severe weather threat was large hail as cold air aloft was associated with the upper level low. The first report of large hail was received around 3:50 PM as 0.75 inch diameter hail fell in Oak Grove in Dillon county. As other storms developed, several other reports of large hail were received with the largest report of 4.5 inches occurring in Florence around 9:10 PM.

Occasional wind damage was reported from some of the storms. The most widespread damage occurred in and around Florence around the time of the large hail during the evening. Numerous trees were knocked down, with some falling on houses. Several building were damages and at least one roof was blown off.

The images below show the base reflectivity, base velocity and vertical integrated liquid (VIL) products from the Wilmington NWS radar around the time of the damage near Florence. The VIL product gives a look at the total amount of water in a thunderstorm and large values indicate the possibility of large hail.

Radar reflectivity image from 9:06 pm.  The storm that produced the 4.5 inch diameter hail and wind damage was just northwest of Florence, SC.

Radar velocity image from 9:06 pm.  Radar estimates of wind speeds were around 50 mph.

Radar VIL (Vertically Integrated Liquid) image from 9:06 pm.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE WILMINGTON NC

TIME(EDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0904 PM    10W FLORENCE              SC   1.25 INCH HAIL
05/25/00   FLORENCE                       REPORTED BY SPOTTER

0905 PM    FLORENCE                  SC   1.75 INCH HAIL
05/25/00   FLORENCE                       SKYWARN SPOTTER REPORTED
                                          AT INTERSECTION OF U.S. 76
                                          AND I-95

0909 PM    FLORENCE                  SC   WIND DAMAGE
05/25/00   FLORENCE                       SKYWARN SPOTTER REPORTED
                                          DAMAGE AT CORNER
                                          OF IRBY AND CHEROKEE
                                          UNCONFIRMED DAMAGE TO
                                          TO BUILDINGS AROUND AREA.
                                          HAIL UP TO SOFTBALL-SIZE.

0909 PM    FLORENCE                  SC   1.75 INCH HAIL
05/25/00   FLORENCE                       REPORTED BY SKYWARN
                                          SPOTTER

0910 PM    FLORENCE                  SC   4.50 INCH HAIL
5/25/00    FLORENCE                       REPORTED BY COUNTY
                                          EMERGENCY PREPARDNESS
                                          COORDINATOR

0912 PM    2S FLORENCE               SC   WIND DAMAGE
05/25/00   FLORENCE                       TRAINED SPOTTER REPORTED
                                          NUMEROUS TREES DOWN SOME ON
                                          HOUSES

0915 PM    3S FLORENCE ARPT          SC   1.75 INCH HAIL
05/25/00   FLORENCE                       REPORTED BY SKYWARN
                                          SPOTTER

0929 PM    EVERGREEN                 SC   2.75 INCH HAIL
5/25/00    FLORENCE                       REPORTED BY HAM RADIO
                                          OPERATOR

0929 PM    FLORENCE                  SC   1.25 INCH HAIL
05/25/00   FLORENCE                       PING BALL-SIZED HAIL
                                          REPORTED BY SPOTTER NEAR
                                          I-95