Parched lawns and fields, drooping gardens and frequent grass fires aren't the only visible evidence that much of Minnesota is in dire need of rain. Some of Minnesota's rivers, particularly the Mississippi and St. Croix, are markedly low. Frequent visitors find their beaches expanding a bit every day — a result of this spring's abnormally early heat wave.

Changing river vistas are yet another indicator of the moderate to severe drought conditions that now cover more than 60% of the state, the result of unusually early hot weather and a dearth of rain.

"It's going to take several pretty big, widespread precipitation events to create some runoff, because the ground has dried out so much," said Brent Hewett, a meteorologist with the National Weather Service's regional office in Chanhassen. Anything less than a half inch of rain will simply soak into the ground on impact, rather than create enough runoff to reach rivers and streams, he said.

And while lower rivers may not present as much as a problem as flooded ones, there could be troublesome ripples.

Lower water levels could impede navigation along the Mississippi River, in particular, if conditions don't improve soon, officials say. The Army Corps of Engineers and the Coast Guard, which oversee river navigation, are closely monitoring water levels.

Right now the below-normal flows aren't causing issues, Corps spokesman George Stringham said Thursday. And if conditions worsen, dredging teams can deepen the river bed and the Corps can narrow the waterway to increase flow.

There are currently no plans to limit travel on the Mississippi, according to Petty Officer Monika Spies of the Coast Guard's St. Louis office. But low water levels might deter some mariners and therefore lighten boat traffic, she said.

Below-average water levels can also make it difficult to load barges, said Lee Nelson of Upper River Services in St. Paul. Barge loads are measured by how far the vessel sinks into the water under a load's weight. If the barge is resting on the bottom of the river bed, it's impossible to tell whether the load is too light, too heavy, or just right.

Some loading terminals have had to call in dredgers because there isn't enough clearance to load properly, Nelson said.

While the current dry weather may feel extreme, the state is nowhere close to the drought conditions it experienced in 2012, 2007 and 1987, said Assistant State Climatologist Pete Boulay.

"We have some ways yet to go with this drought to get to that level, and we're certainly on our way, but we're not there yet," he said.

Boulay cautioned that river "low water records" listed on the NWS website are incomplete and likely don't reflect the actual historic lows.

Consistent precipitation is the only way to raise water levels and navigate out of this drought, river and weather watchers say.

The best chance of rain will come Sunday night, when a cold front moves through the state. Hewett estimated that parts of the state could get up to half an inch of rain, and said temperatures then should return to near-normal levels for the rest of the month.

The northern half of the state will likely remain drier than the southern half for the foreseeable future, he said.

Hopes for more June rain remain alive, but this far into the month that is usually Minnesota's rainiest, "nothing that would be a drought-buster by any means," Hewett said.

Maya Miller • 612-673-7086