At long last, a bit of good news about the drought: It rained.

National precipitation between Aug. 13 and 20. Click to embiggen. (Image courtesy of Intellicast.)

Between 1.0 and 1.5 inches of rain fell across … the upper Midwest [on Thursday], stretching from Iowa through Ohio. Cooler temperatures between 70- to 80-degrees Fahrenheit followed and are forecast to continue through the Labor Day weekend.

The rainfall meant a reduction of land scorched by drought — 61.8 percent of the Midwest this week, down from 62.5 percent last week, according to the National Drought Mitigation Center (NDMC) at the University of Nebraska in Lincoln.

If the drought continues to recede at that rate, the United States will be drought-free in only 88 weeks.

Even a massive, ongoing deluge couldn’t save this year’s crop yield. There’s not enough time to replant corn and soybeans before autumn, so it’s not expected that total output — or futures prices — will get much better.

Nor will this brief rain greatly help the parched Mississippi River. A number of vessels are working to keep the river’s shallower sections passable.

The Army Corps of Engineers has more than a dozen dredging vessels working the Mississippi this summer. Despite being fed by water flowing in from more than 40 percent of the United States, the river is feeling the ruinous drought affecting so much of the Midwest. Some stretches are nearing the record low-water levels experienced in 1988, when river traffic was suspended in several spots. …

When the Mississippi is low, the flow slows and sediment settles, causing the river to silt up and obstructions to form, said James T. Pogue, a spokesman for the corps in Memphis. Since 1988, when record low water on the Mississippi caused navigation to shut down, the corps has engineered ways “to help the river keep itself open,” he said, building new features like dikes that stick out into the river and “sort of act like nozzles to speed up the flow of the river” to scour the bed.

Good news for the various dejected-looking boys standing at the river’s edge next to hand-crafted rafts, swinging dead cats.

Update: The Coast Guard shut down a stretch of the Mississippi because water levels are too low.

“We are allowing a limited number of vessels based on size” to attempt to pass, said New Orleans-based Coast Guard spokesman Ryan Tippets, adding that the closure was affecting 97 vessels Monday afternoon and was halting both northbound and southbound traffic.