A warm, dry and sunny Fourth of July weekend will determine whether Utahns escape the 2011 snowmelt crisis without major flooding — or find themselves once more shoring up sandbag levees along overflowing waterways.

Temperatures Friday settled in the mid-80s for northern Utah and 90s to low 100s in the south. But with highs expected to climb toward the high 90s Saturday and Sunday in the north and upper 90s to near 110 degrees in southern Utah, the National Weather Service issued fresh flood warnings for several of the state’s swollen rivers and creeks.

In Salt Lake County, Little Cottonwood Creek once more was a worry. A flood warning was in effect into early next week, and forecasters warned that the creek could remain near flood levels through Monday.

At dawn Friday, Little Cottonwood was rushing along at 775 cubic feet per second, just below its 800 cfs flood stage; the creek had peaked at 865 cfs just before midnight Thursday and was expected to reach the tops of its banks again early Saturday, as well as Sunday and Monday nights, the NWS said.

Also under flood warning Friday was the upper Weber River in southwestern Summit County. Measured near Oakley, the Weber began the day at 3,133 cfs and 9.71 feet — well above its flood stage levels of 2,510 cfs and 9.2 feet. The river had topped 3,3390 cfs and 9.9 feet earlier Friday morning.

Forecasters predicted the Weber would remain near or over flood stage through the holiday weekend.

Summit County officials were on guard entering the weekend for release of excess water from Wanship Dam into the Weber. It was feared that the spillage could boost flow by up to 10 percent, possibly threatening properties downstream in the Wanship, Echo and Coalville areas.

Also earning flood warning status midday Friday was the Logan River, well above flood stage (1,350 cfs and 5 feet) where it flows through central Cache County. At noon, the Logan was at 1,575 cfs and 5.2 feet, and it levels were expected peak possibly higher through Saturday and into Monday, the NWS said.

Indeed, forecasters warned that the Logan could reach its peak high for the year sometime Monday, threatening the Logan Golf Course downstream.

Cache County’s Spring Creek, near Providence, started Friday under a warning as well, though flooding risks were expected to diminish into Saturday.

Northern Duchesne County’s Uinta and Duchesne rivers, as well as Rock Creek, also were causing concern, and the NWS added those waterways to its official flood warnings. Forecasters blamed accelerated snowmelt from the Uinta Mountains for pushing flows above flood stage.

While no specific flood warnings were in effect for Tooele County, commissioners on Wednesday issued a state of emergency declaration. Public works crews there struggled to keep torrents of snowmelt rushing out of canyons surrounding the Tooele and Rush valleys from damaging roads, bridges and some isolated homes.

Alhough damage has reportedly been minor so far, Tooele County commissioners explained they made the declaration as a first step to seeking state financial assistance to defray rising flood control costs.

remims@sltrib.com