LEWISTON — They don’t put out flood warnings for nothing.

As promised, hard rain in the early evening Thursday left roads flooded in several cities and towns, and crews were scrambling to keep up.

In the Lewiston-Auburn area, the intensity of the rain began to pick up at about 6 p.m. Two hours later, it was still pouring and most streets and side roads had at least one trouble spot.

Lewiston was particularly hard-hit, with several streets washed over. South Avenue, near the corner of Lisbon Street, was covered with water by 8 p.m. The driver of a tractor-trailer plowed through it, but the drivers of other cars turned around and found alternate routes.

Several areas along Lisbon Street were partially flooded, causing traffic to slow to a crawl as drivers crept their way to destinations. Crews were keeping an eye on East Avenue, where massive puddles had formed along some stretches.

Downtown, water was reported over Maple Street, near The Public Theatre, and similar conditions were making travel perilous on Lincoln and Canal streets.

Several streets around Bates College were flooded in spots, including White Street and sections of College Street and Campus Avenue. The problem was exacerbated in some areas by leaves clogging roadside drains.

It was all right on schedule: The National Weather Service had posted flash-flood warnings much earlier in the day. At about 8:15 p.m., those warnings were reissued as weather observers said two inches of rain had already fallen in some areas.

In addition to the Twin Cities, Lisbon, Greene, Leeds, Monmouth, Durham and Minot were expected to have water problems by the end of the night. Weather forecasters said 4 inches of rain might fall before the storm was over.

The NWS online watches and warning page contained ominous advice.

“Move to higher ground now,” one warning stated. “Act quickly to protect your life. Be especially cautious at night when it is harder to recognize the danger of flooding.”

In Auburn, police, fire and Public Works crews were contending with flooded streets and basements in various parts of the city. Police Lt. Laurie Woodhead said they were responding to one report after another and notifying the Auburn Highway Department.

“Trouble spots everywhere,” Woodhead said.

Local and county officials were keeping an eye on Route 136 between Auburn and Durham, a frequent problem area for flooding.

The flood warning was to stay in effect into early Friday morning before clearing was expected.