As Gulf Coast towns shudder and scramble, fearing the deluge of rain and wind that Hurricane Isaac is expected to dump late Tuesday or early Wednesday, the drought-stricken Midwest couldn’t be more thrilled to welcome the storm system. The heartland of the United States has been hoping for rain since May; across the central plains, crops are withering and rivers are running completely dry, strangling local economies.
But for those hoping for a respite from what’s been one of the most ruinous droughts in decades, Isaac may not be bringing salvation. The 1 to 3 inches of rain expected to fall on parched farmland and pastureland in Arkansas, eastern Missouri and central Illinois later this week will provide “a nice shot in the arm,” says National Weather Service meteorologist Jim Keeney. “But most of the crops are already lost and the rain really won’t do much for lakes and streams.”
In fact, it might not even be enough to provide any relief at all. In Missouri, for example, this season’s rainfall is 15 to 20 inches below normal amounts, meaning even 3 inches of rain isn’t going to be enough to end to the drought or save summer corn and soybean crops. “To get out of a drought, we need consistent rains over a long period of time,” Keeney says. “The ground is so dry and hard, it takes a long time for any moisture to percolate down and do any real good. To get back to normal we would need months of above normal gentle rains and that is not in the offering at this time.”
The storm system may even do more harm than good in America’s agricultural breadbasket. Abnormally high winds could push over already brittle unharvested corn stalks, flatten rice plants and knock over the newly-seeded sugarcane crop, according to U.S. Department of Agriculture weather expert Brad Rippey. Also at risk are cotton harvests in Louisiana, where many plants are currently in the “open-boll stage” and vulnerable to rain and wind. The soil is so parched across the central part of the U.S. that a sudden downpour — Isaac’s predicted 1 to 3 inches is on par with a weak hurricane or intense tropical storm — could send the rain sliding off the hard soil, leading to flash flooding, Keeney says. However, because streams and rivers are running so low — if they’re running at all — they are too barren to overflow, limiting the flooding concerns to isolated pockets.
The weather event that does spark concern in the Midwest is the possibility of thunderstorms on Wednesday and Thursday in the storm’s vanguard, especially in Missouri’s Ozarks. The risk of lightning strike-induced fires in areas where the vegetation is dry as kindling is real, although those concerns will certainly dampen if the rain comes along with the lightning.
But despite concerns over flooding, lightning and crop damage, Rippey says that Isaac is “a very important rainfall” for the Midwest, and Keeney says the storm system’s currently predicted path couldn’t get any better, hitting the exact areas of the country in the deepest drought. And even if the current crop can’t be helped, there’s always next season. “We have to look past the summer crops and to the next crop cycle,” Rippey says. As farmers prepare to plant soft red winter wheat this fall, they’ll need the moisture Isaac will bring to soften the ground for planting.
“As we work north to Arkansas and Missouri and the lower Midwest, the rainfall becomes increasingly beneficial in those areas,” Rippey says. “What is not so good for Louisiana or Mississippi, as we move north, is great rainfall.” While it may not be enough to save a dismal summer, every drop helps. As Rippey says, “We welcome the rain with open arms.”