Publication Date:
2021-07-06
Description:
The center of low pressure of a tropical disturbance whichmoved northward in the Gulf of Mexico, reached land betweenPanama City and Port St. Joe, Florida, on September 20, 1969. Thissystem was nearly stationary for 48 hours producing heavy rainfallin the Quincy-Havana area, 70-80 miles northeast of the center.Rainfall associated with the tropical disturbance exceeded 20inches over a part of Gadsden County, Florida, during September 20through 23, 1969, and the maximum rainfall of record occurred atQuincy with 10.87 inches during a 6-hour period on September 21.The 48-hour maximum of 17.71 inches exceeded the 1 in 100-yearprobability of 16 inches for a 7-day period.The previous maximum rainfall of record at Quincy (more than12 inches) was on September 14-15, 1924. The characteristics of thishistorical storm were similar in path and effect to the September1969 tropical disturbance.Peak runoff from a 1.4-square mile area near Midway, Florida,was 1,540 cfs (cubic feet per second) per square mile. A peak dischargeof 45,600 cfs on September 22 at the gaging station on theLittle River near Quincy exceeded the previous peak of 25,400 cfswhich occurred on December 4, 1964. The peak discharge of 89,400cfs at Ochlockonee River near Bloxham exceeded the April 1948peak of 50,200 cfs, which was the previous maximum of record, by1.8 times. Many flood-measurement sites had peak discharges inexcess of that of a 50-year flood.Nearly $200,000 was spent on emergency repairs to roads. Anadditional $520,000 in contractual work was required to replace fourbridges that were destroyed. Agricultural losses were estimated at$1,000,000. (44 page document)
Keywords:
Atmospheric Sciences
;
Tropical depressions
;
Florida
Repository Name:
AquaDocs
Type:
monograph
Format:
application/pdf
Format:
application/pdf
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