HELENA, Mont. - Crews and residents frustrated by a week of major flooding across Montana cleared debris from roadways and some muddied homes on Saturday, even as they braced for more heavy rainfall expected over the Memorial Day weekend.

A respite in weather that has brought as much as 8 inches of rainfall over a span of a few days to some areas of the state had allowed waters to recede slightly in several flooded communities, giving emergency crews the chance to fix water-damaged roads, although they said some would not be repaired before the water is expected to rise again.

But the break in the rain looked to be brief with the National Weather Service predicting up to 3 inches of rainfall from today to Monday, and meteorologist Keith Meier warned the moisture would raise flood waters. High temperatures and melting snow next week would likely swell rivers for even longer, he said.

"Take a little time to breathe today, figure out what you need to do but don't let your guard down," said Cheri Kilby, Disaster and Emergency Coordinator for Fergus County.

Authorities have already started releasing massive volumes of water from overburdened reservoirs. The releases coupled with the floodwaters are predicted to move downstream and causing flooding in the Dakotas, and possibly in Iowa, Nebraska, Kansas and Missouri.

In Bismark, N.D., where the Missouri River was at a flood stage of 16 feet on Saturday, Mayor John Warford said rain and increased water releases from the Garrison Dam had altered flooding models for the region, but he doesn't know how much.

The mayor said the Army Corps of Engineers is recalculating its flooding forecast and was expected to release it early Saturday night. Officials are building levees to protect the city to 21 feet.

North Dakota Gov. Jack Dalrymple also said Saturday that the Federal Emergency Management Agency had expanded its federal emergency declaration to include seven state counties and an Indian reservations fighting rising water on the Missouri River.

FEMA issued an emergency declaration in early April for 14 counties hit with flooding.

In Montana, state of emergencies have been declared in 51 Montana counties, towns and Indian reservations, and the governor deployed Montana National Guard soldiers to the Crow Reservation, one of the hardest hit areas, a day after touring the area.

The guardsmen were setting up unarmed security checkpoints on the Crow Reservation Saturday afternoon to help with emergency response. Crow Tribe officials earlier in the week requested National Guard aid after heavy rainfall put much of the reservation under water and left residents stranded.

Crow Chairman Cedric Black Eagle said the tribal government is helping pump water out of flooded basements and clear off roads so families can return and start to repair their homes.

But Black Eagle said he realizes the waters are still high and people may have to leave the reservation again if waters rise.

To the northwest, continued high waters in Roundup were taking their toll.

The small agricultural community seemed to be retaining much of its flood water and the Musselshell River level was hardly declining, said emergency officials. Road closures have cut the town off from all directions but the north.

Director of Disaster and Emergency services for Musselshell County Jeff Gates said people are still stranded around the town. Gates said there is little emergency crews can do at this point but provide people with supplies they need and wait for water to go down.

Gates said that doesn't look to be likely for quite a while.

He is concerned about the town running out of freshwater and residents are being told to conserve as much as they can.

Businesses are having a hard time getting supplies and residents are mostly helpless to do anything about several feet of water on the southern side of town.

The businesses that have managed to stay open have seen quite a few customers, frustrated with nothing else to do but wait out the water.

Everett Reaves, owner of the Keg Bar in Roundup said a number of people are coming out to his bar.

"When things are down, people go to places like this to forget about it," he said.

Blaine Tull, who runs the Pioneer Cafi in Roundup with his wife, had a different take on the situation and the water conservation.

"Ain't no sense in getting frustrated with something you can't change," he said