Has summer heat finally given way?: This year's heat and drought harshest in Mid-South since 1980

AS THE miserable summer of 2000 gives way to fall, the heat is still a constant source of conversation throughout the Delta. How hot has it been? When has it been worse?

1980 Often 1980 is cited as having been the last summer with such heat and drought. Are the comparisons valid? They're pretty close, says Bart Freeland.

"In 1980, August wasn't nearly as hot as this year. July 1980, on the other hand, averaged 96.3 degrees. This year, the temperature in July averaged 94 degrees. Those temperatures were taken in Stoneville, Miss., and are the average daily maximum temperatures."

This summer, Stoneville has seen 12 days where temperatures have either met or beat previous records. The hottest summer on record was 1930 when the entire month of July averaged over 100 degrees, says Freeland, who works at the Delta Research Extension Center's Weather/GIS Data Center.

"Comparisons in rainfall shows that the 30-year average for July is 3.66 inches. This year we received 0.64 inch. In 1980, we received 1.46 inches."

When talking about this year's heat, a lot of reference points depend on what generation you belong to, says Freeland.

"I had a guy call me last year who said, `Look at 1930. I remember that year as terribly hot.' I pulled the numbers and, sure enough, he was right on the money. That was an awful summer."

20-year event John Grymes, Southern Regional Climate Center senior meteorologist and state climatologist for Louisiana, says most of the Delta is in a 20-year event.

"I can tell you the numbers, but not the impact. When the rain comes is often more important than how much. The `when' is the key.

"There are times when my numbers would even say it's wetter than people would suspect. But because rain comes at bad times, the situation looks incredibly bleak," says Grymes, who works out of Baton Rouge.

Normally, how bad things are also depends on who you're talking to. For example, drought impacts on cotton are different than those on corn. The time-tables are such that lack of rain over a period is a big problem for one farmer and not for another, says Grymes.

This year, however, the drought impacts across the board. While things aren't good anywhere, the problems increase as you travel further south.

"There's a gradient of drought. As you get further south, the situation gets much more critical. In the coastal counties of Mississippi and southeastern quarter of Louisiana, you're talking about drought that is a 100-year event," says Grymes.

The drought map Grymes points farmers to a map of interest - the U.S. Drought Monitor. Updates of the map can be found at http://enso.unl.edu/monitor/monitor.html.

The map does two things, says Grymes. First, it takes a composite of all the various drought indices and tries to group them regionally into the map. Second, unlike most other drought maps - which are driven by data and computer models - this product includes human qualitative interpretations.

"I provide an assessment of conditions in Louisiana and neighboring states. Every week I send in information asking them to make modifications to the map in certain ways. Agents at the USDA actually produce the final map."

What jumps out at a reader is the Southeastern states - centered on Alabama - are far and away the most severely impacted by drought, says Grymes.

"That's somewhat odd to see because the common view is that of swamps in Louisiana, afternoon showers, alligators."

But Louisiana hasn't seen such showers in a long time. Many swamps are bone dry.

"We've had the driest 24-month period ever recorded along with the driest January through August ever. We're literally setting a new rainfall deficit record every day."

Forest fires This will go down in record books not only as the driest year, but also as the biggest forest fire year for Louisiana, says Grymes.

"Few know that we have forest fires burning in almost half our parishes currently. Here it is, the first week of September, and Louisiana has already lost more than double the amount of acreage we normally lose annually to forest fires. It's been absolutely brutal."

Farmers throughout the state have certainly suffered, says Grymes. Agriculture in the southern part of the state - particularly sugar cane farmers - are feeling the heat "big-time."

Getting back to normal Has Grymes looked at what it would take to get back to pre-drought levels of moisture?

"Yes. Most people ask how much rain we need to get back to normal. That's different than how much rain we need to end the drought.

"The environment is forgiving. In some areas in the southeastern part of the state, we're as much as 20 to 25 inches behind for annual rainfall. We're less than half of normal in many other places. That's unheard of this late in the year.

"While we're 20 to 25 inches behind normal, we probably only need about half of that to put a real dent in the drought. Some of that accumulated deficit doesn't really matter."

What is needed in the southern part of the Delta is two or three months of much-wetter-than-normal weather equaling between 10 to 15 inches above the norm. That much rain isn't needed in much of the area between Natchez and Memphis, says Grymes.

"It's still significant, though, probably close to 6 to 10 inches instead of the 10 to 15 needed further south."

Tropical storm - a good thing? Would getting that much rain over a two- to three-month period mean setting a record in the rainfall arena?

"Not if a tropical storm came barreling through. But that isn't a good solution," says Grymes.

Grymes says he keeps hearing Louisiana and Mississippi farmers say the Delta needs a tropical storm to sweep through and dump water on the land. That's a bad idea, says Grymes.

"Ten inches of rain in three days would not be a good solution - it would be a big problem. What's needed is a run of days - of weeks - of steady, intermittent showers. Slow saturation is what's needed."

Part of the answer to how this drought needs to end isn't just how much rain is needed, but how it gets here, says Grymes. A tropical storm on such dry, hard ground would cause much flooding and a lot of soil erosion.

"I think a tropical storm coming now would be more damaging to soil structure than during a typical year."

Surprisingly, getting rainfall in the Deep South on the order of 10 inches above normal over three months isn't far out of the norm. The problem is that fall tends to be the driest season, says Grymes. The likelihood of getting 10 inches above the average for three months is shaky.

"So it's not likely that we'll see a quick resolution to the drought over the next couple of months. The longer-range picture is calling for normal rainfall. If that occurs it would be a blessing. That would give hope for a turnaround.

"I think we can start to look for an end to the dry weather pattern. We should get more-typical rainfall shortly," says Grymes.

But the drought should still be slow to turn around.

"As for the environment, even if we turned things around this week, for some aspects of the environment it will take some time to recover. This dry spell has been in and out of our weather pattern for two years now. This was not a one-summer event. The tendency for drier weather can be tracked back to the spring and summer of 1998."

Temperatures According to meteorologists, the news is promising. But there are caveats, so don't hold your breath.

"We think the dry weather pattern is coming to an end. This winter should be typical," says Grymes.

Temperatures should be normal or a bit above.

"The problem with temperatures - especially with long-range outlooks - is the forecasts are based on three-month periods. That doesn't give us a really good sense of the likelihood of freeze events.

"For example, everyone can remember winters where there were three days in the 70s, three in the 30s and then three more in the 70s. The thermometer would bounce around and the long-term average for the year would still be normal."

"Unfortunately, there aren't very many indicators out there that give a sense of whether this will be a warm winter with lots of fluctuation or a winter that's fairly warm throughout. I'm reluctant to give any forecast on temperatures that suggests when the first freeze will come. Our science isn't good enough to tell that."

Aftermath will linger The one thing that's really important to remind people of is that just because rains may return in the next couple of weeks, the drought effects will linger well into the winter or spring, says Grymes.

What are some of those aspects?

"Mainly I'm talking about soil moisture, about the very shallow aquifers. People that are having well water pressure troubles aren't likely to see things turn around for some time. Before the water gets into the lower aquifers, we've got to recharge the soil moisture.

"Most of our models show the soil is as dry as any since we've been keeping records - but farmers already know that. I'm always hesitant to tell farmers things they already know. I can sit here and look at numbers for weeks but the farmers are out there every day rubbing soil between their fingers. The one thing I can do is put the data in a historical perspective."

In that light, many old-timers say the really bad drought was in the early 1930s. What do the numbers say?

"Well, the 1930s were the Dust Bowl years. Those were terrible in the Southern Plains. But in our neck of the woods, I'm surprised that more people don't cite the 1950s as terribly dry and hot. Drought in the 1950s and early 1960s was more significant in the Southeast than the Dust Bowl years.

"Maybe Hollywood has something to do with that. While the Dust Bowl clearly had a national impact - especially with the large migration westward - there wasn't the same impact around here. It was dry here but nothing horrific."

The Stoneville Weather/GIS Data Center has automated weather stations located throughout the Delta in agricultural areas. Every morning, data from the stations is collected. That information is made available to the public about an hour later. Much of the data is available on the internet at www.deltaweather.msstate.edu.

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