|Excerpts from a preliminary report by the Meteorologist -In-Charge in 1979
To: Acting Director Southern Region of the National Weather Service
Dated : April 20, 1979
On Wednesday afternoon, April 11, heavy thunderstorms moved into the western part of the state. During the next 36 hours, thunderstorms repeatedly developed over much of central Mississippi from Jackson to Columbus.
When it was all over Friday morning, April 13, rain accumulations had totaled 8 inches over the upper Pearl Basin, with amounts between 15 and 20 inches over most of Choctaw, Winston, and Oktibbeha counties in the east central part of the state. These rains caused record flood levels on the Noxubee River (which flows into the Tombigbee River), the Big Black River, and the Pearl River. This report will concern only the Pearl River flooding.
The storm system that set off the heavy rain had already spread devastation at Wichita Falls, Texas and in Oklahoma the previous day. The death toll from the tornadoes there put residents in Mississippi on alert better than any tornado watch. During the day Wednesday, gradient winds blowing up to 45 miles an hour kept everyone nervous and on the lookout.
A tornado watch went up for west and central parts of the state around 5pm. Brief power interruptions (probably due to trees brushing against power lines) forced us to go to emergency power around this time also.
Thunderstorms began moving into the state shortly thereafter, prompting a host of warnings of various types, including flash flood, severe thunderstorm, and tornado.
Around 10:30pm, an extremely heavy thunderstorm moved across the station. Lightning struck the modulator building or radome, shorting everything out and stopping the generator cold. Equipment affected included the radar, the laserfax, the facsimile machine, the river code-a-phones, the WBRR, NOAA Weather Radio consoles, the upper air mini-computer, and RBC, and half of the rest of the equipment used for observations. Much was back in service within a couple of hours, and much more in the next 24 hours, but the radar was out of commission for the duration of the storm. Surrounding Weather Offices helped us tremendously during this crisis. Our operations continued very near normal due to the tremendous team effort by our staff, with help from other weather offices.
This same thunderstorm dumped an amazing 4.5 inches of rain on the station in just over an hour. Similar amounts fell in other parts of town, creating massive drainage flooding. Flash Flood Warnings went out at 10:55pm for the three counties that make up the Jackson Metropolitan area (Hinds, Madison, and Rankin).
The thunderstorms persisted during the night from Jackson to near Columbus. Another heavy thunderstorm at Jackson around 3am dumped an additional 2.35 inches on the station in a 90 minute period. In the headwaters of the Pearl, 8-10 inches of rain was falling.
Sometime during the night, three little girls in Winston County were drowned by flood waters as they tried to evacuate their home with the mother. A Flash Flood Warning was posted by Meridian Weather Service Office around 3am for a number of counties including Winston.
River forecasts issued Thursday morning called for crests near record levels on the upper Pearl, and at Jackson, for Friday and Saturday. It was emphasized that more rain (which was expected) would push the forecast even higher.
More watches and warnings went out Thursday afternoon and evening. Damage from storms was relatively light, occurring mainly near Sardis in Panola County (where 3 trailers were destroyed), Tupelo in Lee County (where some trees and store windows were damaged), and a Columbus in Lowndes County (where an apparent tornado damaged trees and some outbuildings). No injuries were reported.
The thunderstorms abruptly decreased and moved out of the state Friday morning. In their wake, rainfall totals had just about been doubled over the previous day.
Flood stage at Jackson is 18 feet (Flood Stage in 2004 is 28 feet). The previous record had been 37.5 feet in 1902, and the modern day record was 37.2 feet in 1961, just after the completion of Ross Barnett Reservoir. There is little concern in Jackson until after the river reaches 30 feet. The water begins affecting some homes and businesses at about 34 feet.
On April 2, the Pearl at Jackson was 7.9 feet. Rains on April 2-4 pushed the river to near 27 feet, and additional rains on April 7and 8 brought it near 28 feet by Wednesday April 11.
At 6am Friday morning, April 13, the river was at 33.5 feet and rising rapidly. A flood warning was issued at 11:10am Friday, calling for record floods at the gaging points above Jackson. At Jackson, we called for a near record flood (37.5) by Saturday, with indications that it could go higher. Meanwhile, we coordinated with local and state officials, as well as the Corps of Engineers at Mobile, the US Geological Survey, and the Pearl River Valley Authority, who control the Ross Barnett above Jackson.
During the day Friday, reservoir officials (after coordination) decided to try and lower the pool at the reservoir in order to make way for the tremendous amount of water expected a few days later. By Friday evening, we started talking about 40 feet on the gage at Jackson as early as Saturday evening. We emphasized that high stages could occur in northeast Jackson...and at an earlier time than at the Highway 80 bridge.
At 5am Saturday morning, we reached 37.6 feet on the gage, surpassing the old record. Water was continuing to rise at an alarming rate, and caught many people unaware. Many were shocked to see the water approaching homes and businesses they thought were untouchable.
By 7pm Saturday, the river had reached 39.8 feet...the Corps of Engineers Intermediate Region Flood (the 100 Year Flood). The river was showing no tendency to slow down, and we called for the river to reach 41 feet by Sunday. At 10pm Saturday, we started talking about 41.5 feet.
Around 4am Sunday morning, we got a call from the Rankin County Sheriff's Office that one of the levees on the Rankin County side of the river had broken. A Flash Flood Warning was issued, but we were told that the levee was just leaking badly and had been brought under control.
During the previous 24 hours, crests were reached at the gaging points above the dam. All crested at record levels. We continued to emphasize these facts in our releases.
By 5am Sunday, the river reached 41 feet. We called for the river to go to 42 feet Sunday afternoon.
Rumors of levee breaks and the dam breaking and of plans to dynamite the dam became rampant. Panic gripped some when helicopters flew over areas at 3am Sunday calling for people to evacuate.
We had a difficult time getting accurate information and reports, and had to spend a lot of time trying to verify reports.
Meanwhile, communications were breaking down. Water had closed a number of Mississippi Power and Light (Now Entergy) substations, and power outages were threatened. Phones were either jammed or out completely. We could no longer get through to the gage since apparently half of Jackson now had the number to it. It was increasingly difficult to talk with reservoir officials. Eventually their phones failed. the Jackson-Hinds Emergency Operations Center had been flooded out and had moved to cramped, unfamiliar quarters in the police communications center, where they had no weather wire or NAWAS, and all phone numbers were different. We were nearly isolated as far as communications was concerned.
The HAM Radio operators (HAM operators continue to be a valuable source of information for the National Weather Service) came to our rescue. They set up bases at the Weather Forecast Office, at the Highway 80 bridge near the telemark and wire weight, and at the reservoir control tower. Earlier, they had set up bases at State CD, the Red Cross, the Corps of Engineers, Mississippi Power and Light, South Central Bell, and Jackson-Hinds EOC. Without them, we would have been lost.
By 4pm Sunday, the river was at 42.1 feet and the rate of rise was clearly slowing down. But it was still very difficult to tell where it would stop because of the ponding.
We now called the river to reach 42.5 feet by Sunday evening. At noon the next day, it was 42.8 feet and we started talking about the river going to 43 feet.
On the Rankin County side of the river, hundreds perhaps thousands of volunteers worked feverishly night and day to keep the levees intact. By the time they were through, they had added about 3 feet to their levee...and incredibly, it held.
The river finally crested out at 43.25 feet (Revised upward by the United States Geological Survey to 43.28 feet) around 3pm Tuesday afternoon. The final toll showed 15,000 people evacuated and an estimated 500 million dollars damage. Many homes in the northeast section of the city, some valued at $120,000 and up, were under water for a week. Many businesses in the downtown area were flooded out when backwater flooding from a creek that runs through town got in them. Other businesses received water when the river flood waters came at them from around a levee built to protect them. Only one death occurred in the Jackson area, when a little girl fell off the porch of her home into the flood waters.
If there was any success from our efforts, it was only because the entire staff pitched in to help. It was truly a maximum team effort, and the services of everyone involved. We particularly appreciated the efforts of a hydrologist from the RFC at Slidell (Lower Mississippi River Forecast Center) for coming up to Jackson on short notice and staying for the duration. We also had tremendous cooperation from the entire RFC Slidell staff.
Several people shared in writing the releases. They went out with remarkably few errors. An office Meteorologist Intern, was a great help in collecting data, and in editing and proofing releases. Most releases originated with my Principal Assistant (PA).
Our work experience employee, made a tremendous contribution. He spent two complete nights and part of one day at the Highway 80 river gage, providing accurate and timely river readings to the world every 30 minutes. The HAMs set up a station there and relayed the data. His willingness to do anything needed and his dependable, accurate readings were vital to our ( and everyone else concerned) continuing operation.
Forecasting a record flood is difficult. We issued frequent statements and told what we knew, and many people listened to NOAA Weather Radio have praised our efforts. BUT NO ONE WAS PREPARED FOR A FLOOD OF THIS MAGNITUDE.
The story is not over. The record flood waters continue at this time down the lower Pearl, and the threat of heavy rain for this weekend looms to the west of us. We will try to keep up with it as we go.