A statewide burn ban takes effect at 9 a.m. Wednesday, an order issued because of persistently dry weather that has caused severe to exceptional drought over 90 percent of Louisiana, state officials said.

Louisiana Fire Marshal Butch Browning Jr. and Louisiana Agriculture and Forestry Commissioner Mike Strain issued the cease and desist order Tuesday.

The ban takes effect on the first day of the June 1-Nov. 30 hurricane season and after weeks of flooding fears from the swollen Mississippi River.

The paradoxical mix of climatic threats raises the possibility of simultaneous federal declarations for both flood and drought in some parishes now coping with Morganza Spillway inundations, state and federal officials said.

Land in these areas may be either in severe or extreme drought conditions or inundated, depending on what side of the levees it lies, the officials said.

State Climatologist Barry Keim said the first five months of 2011 were the second-driest January-through-May period on record in Louisiana.

According to data provided by Keim, average rainfall in Louisiana, at 14.5 inches, is about 10.1 inches behind the state average at this point in the year. Records go back to 1895.

“What we have now is not unprecedented, but it’s extraordinary,” Keim said.

Rainfall at Baton Rouge Metropolitan Airport currently is about 9.4 inches behind the average, according to the National Weather Service in Slidell. The forecast this week is for continued low chances of rain.

Fire Marshal Browning said private burning, such as of trash or debris, is banned until further notice or unless parish governments or fire departments allow it.

Burning that is part of generally accepted agricultural practices is allowed, Browning said.

Strain said the drought could lead to lower crop yields or force more irrigation that raises farmers’ costs.

“In some areas, it’s the driest it’s been in almost 100 years,” he said.

State Climatologist Keim said heavy storms have pounded the central part of the nation with rainfall for months, sending heavy runoff in rivers flowing south.

The storm track has stayed in that area due to a weak La Niña and, as a result, left the Gulf Coast high and dry, Keim said.

“The Mississippi River floods are actually related to our droughts. That’s kind of the irony of this whole thing,” he said.

La Niña is associated with cooler-than-normal water temperatures in the central and eastern tropical Pacific Ocean that can affect global weather patterns, according to the National Oceanic and Atmospheric Administration.

Fire officials from rural departments in Central as well as in both West Feliciana and Livingston parishes and elsewhere welcomed the ban Tuesday, saying they had been dealing with brush, debris or grass fires in recent weeks.

“I think it was well-needed,” said Derek Glover, a captain in the Central Fire Department.

Assumption and Ascension parishes issued their own burn bans Tuesday, officials in those parishes said in news releases.

Browning said a few other parishes had already issued bans, including St. Tammany, Allen and Vermilion parishes.

Outdoor burning in East Baton Rouge Parish is greatly limited normally.

Comparing the January to May periods of 2010 and 2011, the number and size of wildfires statewide are also up, state forestry officials said.

In 2010, 987 fires scorched 10,296 acres while 1,336 fires burned 15,361 acres in 2011, officials said.

Twenty-nine percent of those fires were in the Florida Parishes, State Office of Forestry official Don Smith said.

Strain has a pending request with U.S. Agriculture Secretary Tom Vilsack for a disaster declaration for Morganza flooding.

Some livestock owners in some parishes affected by flooding are eligible for federal drought assistance automatically tied to a NOAA drought map, a federal farm official said.

The U.S. Drought Monitor map combines several methods to assess drought conditions, including precipitation, Keim said.

Willie Cooper, state director for the U.S. Department of Agriculture Farm Service Agency in Alexandria, said eligible livestock owners in 53 parishes qualify for the drought assistance, including St. Landry and Pointe Coupee parishes.

“What it boils down to is we’re flooding from other people’s water, and we’re burning up,” he said.

Cooper said payments under the two declarations — should the one covering flooding also be granted — cannot be duplicated.