Heavy rain and snowfall over the greater Mississippi River Basin have caused an unseasonable rise in the Mississippi River locally, which could parlay into spring flooding for a third straight year in Vicksburg.

While a winter rise is not uncommon, this year’s rise comes with a troublesome forecast.

Mississippi River

on Dec. 30

2001    37.0

2002    30.7

2003    21.9

2004    33.4

2005    4.8

2006    18.0

2007    28.2

2008    24.3

2009    34.7

“We’ve been in a very active weather pattern lately as far as precipitation, and I think that pattern is going to continue — which is probably the last thing people around here want to hear,” said Mark McAllister, meteorologist for the National Weather Service in Jackson. “It could make for a very wet spring.”

The Mississippi River at Vicksburg was running at 34.7 feet this morning, a rise of a half-foot in a 24-hour period. The river is nearly twice as high as it normally is this time of year, but crests upstream indicate levels will recede before the official flood stage of 43 feet is seen at Vicksburg.

“It would normally be at around 19 feet right now, and we’re already over 34 feet today,” said Tim Rodgers, hydraulic engineer for the U.S. Army Corps of Engineers.

The Lower Mississippi River Forecast Center said the nation’s largest waterway will crest at Cairo, Ill., on Thursday at 1 foot above flood stage. The river at Vicksburg is expected to be at 35.8 feet on Sunday, but the forecast center has not yet posted a crest prediction for the local gauge.

“October is normally a very dry part of the year, but this year the Mississippi River Basin received a tremendous amount of rain,” Rodgers said. “The entire region basically got 200 to 300 percent of normal rainfall for the month, and that’s why the river is as high as it is now.”

Rainfall at the Vicksburg Water Treatment Plant measured 14.47 inches in October, more than four times the local average of 3.8 inches for the month. While it is not reflected in readings on the Mississippi here, year to date, Vicksburg has received 61.03 inches of rain — nearly 10 inches more than the annual average of 51.18 inches.

McAllister said other areas of the state have received nearly 80 inches of rain over the year, compared to regional averages around 55 inches. Further up river, the same has been true. St. Louis, for example, has received 50.84 inches of rain this year — 12.4 inches more than usual.

Many Midwestern cities and states, meanwhile, are wrapping up the snowiest December on record. Des Moines, Iowa, for example, received just under 28 inches of snow this month, more than 6 inches above the monthly average. While there will not likely be any immediate flooding due to the rainfall runoff, Rodgers said it’s hard to predict how the spring snowmelt will affect the river at Vicksburg.

“The snowfall isn’t done up North yet, and we really don’t have a feel for what the effect will be this spring,” he said. “All we can say is we’re higher than we’d like to be at this point.”

Spring snowmelt brings the largest volume of water flowing past Vicksburg toward the Gulf of Mexico.

In 2008, the river topped flood stage in Vicksburg on March 29, crested at 50.9 feet on April 19 and did not recede below flood stage until May 10. It was the highest measured river stage recorded at the city in 35 years, dating back to 1973 when the river topped out at 51.6 feet. This year, the river rose above flood stage on May 13 and topped out at 47.5 feet on May 27.

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Contact Steve Sanoski at ssanoski@vicksburgpost.com