An un-seasonal amplified upper level trough and attendant surface front moved into the forecast area during the afternoon and evening hours. Strong differential positive vorticity advection, high surface based instability, large CAPE in the hail growth zone and low level forcing spawned widespread severe storms.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS JAX wrote it up.
An un-seasonal amplified upper level trough and attendant surface front moved into the forecast area during the afternoon and evening hours. Strong differential positive vorticity advection, high surface based instability, large CAPE in the hail growth zone and low level forcing spawned widespread severe storms. Aloft cool 500 mb around -10 degrees Celsius were noted and mid level dry air moved over the area, and both factors increased downdraft strength in storms.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Jacksonville, FL wrote its last area forecast discussion before the first event at Jul 21, 1:48 PM EST, 1 hour 32 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 248 PM EDT SAT JUL 21 2007 ...SEVERE TSTM WATCH FOR THE SOUTHERN PORTION OF THE AREA THROUGH 9 PM EDT... .DISCUSSION...SO FAR SO GOOD...WE HAVE A BIT OF CONVECTION FIRING UP ON AN OLD BOUNDARY IN CHARLTON COUNTY GEORGIA BUT OTHERWISE WE REMAIN CONVECTION FREE. THAT IS LIKELY TO CHANGE SOON AS MARION COUNTY HAS CLEARED OUT MUCH EARLIER THAN ELSEWHERE AND WE HAVE GOOD CAPE IN THE LOW LEVELS AND COLD AIR ALOFT. THIS SHOULD PRODUCE A GOOD LAPSE RATE OVER THE COUNTY WITH THE MOST PRONOUNCED BOUNDARY BEING THE PRETTY SHARP BOUNDARY BETWEEN THE CLOUD COVERAGE AND THE CLEAR SKIES OVER THE NORTHERN PORTION OF THE COUNTY. BET THERE WILL BE ENOUGH TEMP CONTRASTS FOR CONVECTION TO FIRE THERE FIRST THIS AFTERNOON. HOPEFULLY ALL OF THE SEVERE STUFF STAYS SOUTH OF THE FORECAST AREA BUT IF I HAD TO BET ID PLACE MY MONEY ON SOMETHING HAPPENING IN MARION COUNTY. LOOKING AT THE SYNOPTIC SITUATION I HAVE TO ASK...IS THIS JULY? AS ALMOST LOOKS MORE LIKE A WINTER TIME TYPE PATTERN THAN MID SUMMER WITH A CLOSED UPPER LEVEL LOW OVER THE APPALACHIANS AND AN OLD FRONTAL BOUNDARY DRAPED ACROSS NORTH FLORIDA. THE FRONT WILL REMAIN ACROSS THE AREA FOR THE NEXT SEVERAL DAYS WITH COLD AIR ALOFT. SO EXPECT THE BEST CHANCE OF RAIN AND CONVECTION TO BE ACROSS THE FLORIDA PORTION THROUGH MONDAY WHERE THE GREATEST LIFT AND MOISTURE WILL BE CONCENTRATED. AS A RIDGE OVER THE MID- ATLANTIC STATES SHIFTS EAST THE RETURN FLOW WILL BRING INCREASING MOISTURE OUT OF THE GULF AND A RETURN TO NORMAL DIURNAL CONVECTION ACROSS THE ENTIRE AREA FOR NEXT WEEK. IN THE EXTENDED THE UPPER LEVEL LOW SLOWLY RETROGRADES AND DECAYS OVER THE MID WEST WITH THE MID-ATLANTIC RIDGE RE-ESTABLISHING ITS SELF ACROSS THE REGION INTO NEXT WEEKEND. && .AVIATION...VFR CONDS CONTINUE EXCEPT IN AREAS NEAR STORMS. AS WINDS SHIFT NE-E... OCCASIONAL MVFR CONDS WILL BE POSSIBLE EARLY SUNDAY MORNING FOR TAF SITES NEAR COAST. && .MARINE...NO HEADLINES. AS TROUGH SETTLES SOUTH OF THE AREA WINDS WILL SHIFT TO ONSHORE SUNDAY AND MONDAY. THEN A RIDGE WILL BUILD OVER THE WRN ATLANTIC SETTING UP SLY FLOW FOR REMAINDER OF NEXT WEEK. && .PRELIMINARY POINT TEMPS/POPS... AMG 69 90 66 91 / 30 40 10 20 SSI 74 85 71 85 / 40 50 10 20 JAX 71 87 68 87 / 50 60 20 30 SGJ 74 82 72 84 / 60 70 20 40 GNV 71 87 69 87 / 50 70 30 40 OCF 72 87 69 87 / 50 70 30 50 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && SANDRIK/TRABERT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE JACKSONVILLE FL 1122 AM EDT SAT JUL 21 2007 FLZ020>025-030>033-035>038-040-GAZ132>136-149>154-162>166-212200- ALACHUA-APPLING-ATKINSON-BACON-BAKER-BRADFORD-BRANTLEY- CAMDEN (COASTAL)-CAMDEN (INLAND)-CHARLTON-CLAY-CLINCH-COFFEE- COLUMBIA-DUVAL-ECHOLS-FLAGLER-GILCHRIST-GLYNN (COASTAL)- GLYNN (INLAND)-HAMILTON-JEFF DAVIS-MARION-NASSAU-PIERCE-PUTNAM- ST JOHNS-SUWANNEE-UNION-WARE-WAYNE- 1122 AM EDT SAT JUL 21 2007 THIS OUTLOOK IS FOR NORTHEAST FLORIDA AND SOUTHEAST GEORGIA. THIS AFTERNOON AND TONIGHT... ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE SOUTHERN COUNTIES UNTIL 9 PM EDT... A COLD FRONT WILL SAG TO NEAR THE FLORIDA-GEORGIA LINE TODAY. THIS FEATURE IN COMBINATION WITH AN UPPER LEVEL DISTURBANCE WILL LEAD TO SCATTERED TO NUMEROUS THUNDERSTORMS ACROSS NORTHEAST FLORIDA AND EXTREME SOUTHEAST GEORGIA. ISOLATED SEVERE STORMS WILL BE POSSIBLE THIS AFTERNOON AND EVENING...IN AND NEAR THE WATCH AREA. LARGE HAIL UP TO ONE AND ONE HALF INCH IN DIAMETER AND DAMAGING WINDS WILL BE THE PRIMARY CONCERNS WITH THESE STORMS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY... SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED EACH DAY WITH STRONG TO SEVERE THUNDERSTORMS POSSIBLE SUNDAY AFTERNOON AND EVENING. .SPOTTER INFORMATION STATEMENT... SPOTTERS ACTIVATION IS REQUESTED ACROSS NORTH FLORIDA FOR THIS AFTERNOON AND THIS EVENING. FOR ADDITIONAL INFORMATION...VISIT THE NATIONAL WEATHER SERVICE IN JACKSONVILLE WEBSITE ON THE INTERNET AT WEATHER.GOV/JAX. SANDRIK
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE JACKSONVILLE FL 308 PM EDT SAT JUL 21 2007 GAZ150-164-212000- CHARLTON-WARE- 308 PM EDT SAT JUL 21 2007 ...A SIGNIFICANT WEATHER ALERT HAS BEEN ISSUED FOR CHARLTON AND WARE COUNTIES FOR STRONG WINDS...SMALL HAIL AND EXCESSIVE LIGHTNING VALID UNTIL 400 PM EDT... AT 308 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM CENTERED 13 MILES NORTHWEST OF ST. GEORGE...OR 15 MILES SOUTHEAST OF STEVEN FOSTER STATE PARK...MOVING EAST AT 15 MPH. THIS STRONG THUNDERSTORM WILL ALSO AFFECT AREAS AROUND ST. GEORGE THROUGH 400 PM EDT. HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND LIGHTNING AND GUSTY WINDS OF 45 TO 55 MPH CAN BE EXPECTED ALONG WITH POSSIBLE MINOR DAMAGE. REPORT DAMAGE TO THE NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT. HURLBUT
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE JACKSONVILLE FL 327 PM EDT SAT JUL 21 2007 FLZ024-GAZ164-212015- CHARLTON-NASSAU- 327 PM EDT SAT JUL 21 2007 ...A SIGNIFICANT WEATHER ALERT HAS BEEN ISSUED FOR CENTRAL CHARLTON AND NORTHWEST NASSAU COUNTIES FOR STRONG WINDS...SMALL HAIL AND EXCESSIVE LIGHTNING VALID UNTIL 415 PM EDT... AT 327 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM CENTERED 8 MILES WEST OF HILLIARD...MOVING SOUTHEAST AT 5 MPH. THIS STRONG THUNDERSTORM WILL ALSO AFFECT AREAS AROUND HILLIARD THROUGH 415 PM EDT. HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND LIGHTNING AND GUSTY WINDS OF 45 TO 55 MPH CAN BE EXPECTED ALONG WITH POSSIBLE MINOR DAMAGE. HEAVY RAINFALL WILL PRODUCE PONDING OF WATER ON ROADWAYS AND MINOR FLOODING OF LOW-LYING AREAS. REPORT DAMAGE TO THE NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT. ZAPPE
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE JACKSONVILLE FL 342 PM EDT SAT JUL 21 2007 FLZ040-212045- MARION- 342 PM EDT SAT JUL 21 2007 ...A SIGNIFICANT WEATHER ALERT HAS BEEN ISSUED FOR EXTREME SOUTHWESTERN MARION COUNTY FOR STRONG WINDS...SMALL HAIL AND EXCESSIVE LIGHTNING VALID UNTIL 445 PM EDT... AT 342 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM CENTERED 2 MILES EAST OF DUNNELLON...OR 7 MILES SOUTH OF RAINBOW LAKES ESTATES...MOVING EAST BETWEEN 5 AND 10 MPH. THIS STRONG THUNDERSTORM WILL ALSO AFFECT AREAS AROUND RAINBOW LAKES ESTATES AND DUNNELLON THROUGH 445 PM EDT. HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND LIGHTNING AND GUSTY WINDS OF 45 TO 55 MPH CAN BE EXPECTED ALONG WITH POSSIBLE MINOR DAMAGE. HEAVY RAINFALL WILL PRODUCE PONDING OF WATER ON ROADWAYS AND MINOR FLOODING OF LOW-LYING AREAS. REPORT DAMAGE TO THE NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT. ZAPPE
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE JACKSONVILLE FL 347 PM EDT SAT JUL 21 2007 FLZ023-212045- BAKER- 347 PM EDT SAT JUL 21 2007 ...A SIGNIFICANT WEATHER ALERT HAS BEEN ISSUED FOR NORTHERN BAKER COUNTY FOR STRONG WINDS...SMALL HAIL AND EXCESSIVE LIGHTNING VALID UNTIL 445 PM EDT... AT 347 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM CENTERED 2 MILES NORTH OF TAYLOR...OR 21 MILES SOUTHEAST OF FARGO...MOVING SLOWLY EAST 5 TO 10 MPH. THIS STRONG THUNDERSTORM WILL ALSO AFFECT AREAS AROUND TAYLOR THROUGH 445 PM EDT. HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND LIGHTNING AND GUSTY WINDS OF 45 TO 55 MPH CAN BE EXPECTED ALONG WITH POSSIBLE MINOR DAMAGE. HEAVY RAINFALL WILL PRODUCE PONDING OF WATER ON ROADWAYS AND MINOR FLOODING OF LOW-LYING AREAS. REPORT DAMAGE TO THE NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT. ZAPPE
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE JACKSONVILLE FL 353 PM EDT SAT JUL 21 2007 FLZ040-212100- MARION- 353 PM EDT SAT JUL 21 2007 ...A SIGNIFICANT WEATHER ALERT HAS BEEN ISSUED FOR EXTREME EASTERN MARION COUNTY FOR STRONG WINDS...SMALL HAIL AND EXCESSIVE LIGHTNING VALID UNTIL 500 PM EDT... AT 353 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM CENTERED 3 MILES EAST OF JUNIPER SPRINGS...MOVING SOUTHEAST AT 5 MPH. THIS STRONG THUNDERSTORM WILL ALSO AFFECT AREAS AROUND JUNIPER SPRINGS THROUGH 500 PM EDT. HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND LIGHTNING AND GUSTY WINDS OF 45 TO 55 MPH CAN BE EXPECTED ALONG WITH POSSIBLE MINOR DAMAGE. HEAVY RAINFALL WILL PRODUCE PONDING OF WATER ON ROADWAYS AND MINOR FLOODING OF LOW-LYING AREAS. REPORT DAMAGE TO THE NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT. ZAPPE
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE JACKSONVILLE FL 416 PM EDT SAT JUL 21 2007 FLZ025-212100- DUVAL- 416 PM EDT SAT JUL 21 2007 ...A SIGNIFICANT WEATHER ALERT HAS BEEN ISSUED FOR DUVAL COUNTY FOR STRONG WINDS...SMALL HAIL AND EXCESSIVE LIGHTNING VALID UNTIL 500 PM EDT... AT 416 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS CENTERED 12 MILES WEST OF JACKSONVILLE INTERNATIONAL AIRPORT...OR 8 MILES SOUTHWEST OF CALLAHAN...MOVING EAST AT 20 MPH. THESE STRONG THUNDERSTORMS WILL ALSO AFFECT AREAS AROUND JACKSONVILLE INTERNATIONAL AIRPORT...OCEANWAY...DOWNTOWN JACKSONVILLE... TALLYRAND...FORT CAROLINE AND ARLINGTON THROUGH 500 PM EDT. HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND LIGHTNING AND GUSTY WINDS OF 45 TO 55 MPH CAN BE EXPECTED ALONG WITH POSSIBLE MINOR DAMAGE. IF FURTHER INTENSIFICATION OCCURS A WARNING MAY BE REQUIRED. REPORT DAMAGE TO THE NEAREST LAW ENFORCEMENT AGENCY OR YOUR COUNTY EMERGENCY MANAGEMENT. HURLBUT
The Jacksonville radar (KJAX), 26 km away, was scanning. The volume nearest the first event began at 20:22 UTC.
13 thunderstorm wind, 3 hail, 1 wildfire, 1 funnel cloud, 1 heavy rain. Local standard time, as filed.
Large tree limbs and power lines were blown down along Highway 301 and Motts Road for 3-4 miles. Power outages were also reported.
Trees and power lines were blown down along Highway 301 near Bryceville.
Trees and power lines were blown down over the road at the intersection of Southeast 107 Court and Southeast 132nd Place in Lake Weir. Trees and power lines were also blown down at 11890 Southeast Sunset Harbor Road in Lake Weir.
Dime and quarter size hail was reported in Moss Bluff.
Trees and power lines were blown down near Attleboro Road, about 2 miles west of the Normandy area.
Trees and power lines were blown down near New Kings Road and Edgewood, both on the northwest side of Jacksonville.
A downburst occurred over Orange Park and Fleming Island around 530 pm local time. At 530 pm, a former NWS employee in Orange Park reported a wall cloud with strong rotation. The cloud snapped tree tops in the neighborhood. A roof was also blown off a home on Arbor Circle Drive. By 532 pm, numerous trees were down in Doctors Inlet and Fleming Island. Trees were blown down across the CSX railroad tracks in Doctors Inlet and a gas station also suffered tree damage. At 540 pm, winds were gusting around 50 mph and pea size hail was reported on Fleming Island. Wind gusts snapped a pine tree which fell and damaged a screened room in Eagle Harbor. By 545 pm, widespread tree damage occurred on the southern tier of Fleming Island, south of Hibernia and north of Black Creek. Tree tops were snapped and blown off in Fleming Island Plantation, and some were blocking roads in the subdivision. Minor damage occurred to a mobile home on Floyd Street and a cabinet shop off of Ebb Tide Road and U.S. Highway 17 had roof damage. A portion of the baseball backstop at St. Johns Country Day School on Doctors Lake Drive was bent and several large trees on campus were snapped or uprooted.
A spotter reported penny size hail on Fleming Island around 545 pm local time. By 550 pm, quarter size hail was occurring over Highway 17 in Green Cove Springs. Thunderstorm winds also downed trees and caused roof damage in Green Cove around this time.
A roof was blown off of a home in Green Cove Springs.
Trees and large tree limbs were blown down about 5 miles southeast of Fruit Cove.
Large tree limbs were blown down near Hastings. Tree limb diameters were 8-10 inches.
A spotter reported 4-5 large oak trees were blown across State Road 26, about 1 mile west of Orange Heights.
Trees were blown down in White Springs.
Power lines were blown down in Bostwick.
Numerous trees were blown down in Elkton. Power lines were blown down near Hastings.
A lightning strike caused a temporary brush fire about 5 miles north of St. Augustine Airport.
Several reports of a funnel cloud were received between 802-811 pm local time. The cloud formed over the south end of Amelia Island over Nassau Sound. One report said that it touched down as a waterspout; another report said that the cloud lifted back up into the parent cloud.
Dime to quarter size hail was reported in Moss Bluff.
A spotter in the Normandy area measured 2.81 inches of rainfall in the afternoon and evening.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2007Every state in 2007This day in weather historyWarnings in Florida, July 2007
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 44929, 44930, 44931, 44926, 44933, 44935, 44942, 44927, 44945, 44947, 44949, 44950, 44951, 44952, 44953, 45382, 44924, 44954, 44928.