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Comite River is pictured as Tropical Storm Barry approaches on Saturday, July 13, 2019.

National Weather Service forecasts for river flooding in the Baton Rouge region remained alarmingly high Saturday afternoon even as predictions of rainfall for the region fell with Hurricane Barry's path slipping farther west than expected.

But, with a fairly dry start to Saturday, some local officials speculated that forecasts might drop from projections that suggested flooding from Barry would approach, or even exceed, what happened in August 2016.

In the days leading up to Barry's arrival as a Category 1 hurricane, the National Hurricane Center put out potential rainfall maps that appeared to show the Baton Rouge area would likely receive between 10 and 20 inches of rain, and possibly more in isolated areas.

Those estimates helped inform equally troubling river forecasts.

Perhaps most shocking on late Friday was the sharply reappraised flood crest for the Comite River at Joor Road at 34.5 feet on Monday, which would surpass what the river reached in the devastating August 2016 flood by three-tenths of a foot.

But the latest rainfall maps Saturday afternoon from the hurricane center have dropped the rainfall range to 6 to 10 inches for the Baton Rouge area.

Rick Webre, the Ascension Parish homeland security director, suggested Saturday that river level forecasts would drop in the next 24 hours if rainfall remained less intense than initially feared, even as officials continued to warn residents to stay vigilant Saturday.

Still, observers warned there was still plenty of uncertainty about what effect Barry would ultimately have until forecasters have a better sense of how much rain actually falls on the Baton Rouge area.

Bob Jacobsen, a hydrologist for the Amite River Basin Commission, noted that the early river forecasts are made from rainfall forecasts, essentially a forecast from a forecast. 

He said he doesn't know if the river forecasts will change soon but said he would not be surprised if they do drop at some point because rainfall forecasts seem to be lessening also.

"But, on the other hand, if we get hammered between 4 o'clock this afternoon and midnight tonight, you know, we'll all be saying, 'Well, you know, gosh, why did they dial it back,' you know, so," Jacobsen said on Saturday afternoon. "If I was a forecaster, I would just say, 'Hey, it is what is at this point. I'm giving you guidance.'"  

In a tweet Saturday, Steve Caparotta, a meteorologist with WAFB-TV in Baton Rouge, likewise noted that forecasters might be hanging on to their river predictions for the time being just in case some of Barry's potent pockets of rain, known as rain bands, lock in on one area and dump plenty of precipitation.

"The concern is that one well placed, stationary rain band could still produce big time rains," Caparotta wrote.

Kevin Gilmore, a meteorologist with the National Weather Service office in Slidell, said that if river prediction changes are going to come, they'll likely come even sooner than 24 hours, by Saturday night.

Several weather experts have noted the rainfall maps from the hurricane center denoted "potential rainfall" and aren't necessarily an indication that the maximum amounts depicted will fall uniformly across an entire area but could reflect spots that receive more or less rain.

Jacobsen added that the Weather Service forecasts tend to become really "tight" once officials have enough rainfall data to show what a storm has actually dropped. 

"We’re all going to keep an eye on how much rain hits the ground," he said.

Email David J. Mitchell at dmitchell@theadvocate.com

Follow David J. Mitchell on Twitter, @NewsieDave.