The number of people "unaccounted for" in Larimer County has more than tripled, reports the Sheriff's Office.

Sheriff Justin Smith said Saturday evening about 350 people are presently unaccounted for, up from about 100 earlier in the day.

County officials reported Saturday morning a possible fifth flood victim. A 60-year-old woman from the Cedar Cove area is presumed dead after her house was destroyed by flood waters, the Larimer County Sheriff's Office reported.

No other information was released about that case, but the Sheriff's Office said an investigations team was created to collect and track reports of missing people. A hotline was established at 970-498-5500 to collect reports about individuals who are out of contact with family or friends. The list grew to about 100 named by 11:30 a.m.

"We do estimate that potentially there will be other loss of life," said Nick Christensen, executive officer of the Larimer County Sheriff's Office, during a Saturday afternoon press conference.

Boulder, Colorado -- As furious waters flow through flood-devastated northern Colorado, fears and tales of devastation grow.

At least four people have been killed and 218 are unaccounted for, officials say.

The nightmare is far from over as the state awaits more rainfall Saturday, threatening to send swollen rivers gushing through streets choked with debris. The rain is expected to come down heavy Sunday.

It will not be as much as the 15 inches dumped in some spots this week, but it could cause more flooding in areas where water has already receded, forecasters warned.

Emergency management officials on Saturday were trying to reach those who are missing to ensure they are not in danger. The number of missing is expected to decrease as the effort moves forward.

Residents got some relief Friday when rains subsided, giving a clear view of towns turned into abrupt lakes, homes and businesses inundated with muddy water and bridges devoured by raging creeks. Homes dangled off cliffs.

In Larimer County, there were 46 medical rescues on Friday, and teams continued looking for those unaccounted for on Saturday.

"We hope the worst has passed," John Schulz of the Larimer County Sheriff's Office said. "The water levels are receding, and it was a quiet night overall. We are expecting more rain tomorrow, but with the levels receding today we hope tomorrow is better."

Hundreds of residents were evacuated Friday, including 162 people transported by air from Jamestown because roads to the city were impassible, Boulder County EMS spokesman Ben Pennymon said.

Rescuers have retrieved the bodies of the four who died in the waters. Many more people are cut off by devastated roadways, and authorities don't know how long it will take to reach them.

'My mom's house is gone' Colorado flooding turns deadly Flood victim family: We made it

Gov. John Hickenlooper warned an extensive recovery is ahead for the affected area from the state's center into the northeast.

"This is not going to get fixed in a week," he said. "We have lost a great deal of infrastructure."

People who find themselves caught outside during electrical storms are cautioned to stay away from tall trees, and the accompanying footage provides explosive visual proof of why this is potentially life-saving advice.

A security camera in North Jackson, Tennessee, captured the violent strike Tuesday afternoon. We've provided a red arrow in the top image, pointing to what looks to be a lightning bolt running the down length of a large tree trunk (watch the footage carefully between 4 and 5 seconds).

Two tornado-like water spouts formed on Lake Michigan Thursday, posing little danger but prompting questions from curious onlookers. The waterspouts, funnel clouds that often form on the Great Lakes in the fall when cold air blows over warmer lakewater, are usually much weaker than land tornadoes.

Thursday's, which appeared off the western coast of Lake Michigan, north of Chicago, lasted about 15 minutes and caused no damage. "We did get a number of calls from people who wanted to know what was going on," said Kenosha, Wisc., Police Capt. Tom Hansche. Students in Kenosha Unified School District began emergency weather precautions but returned to class after about 20 minutes.

Federal officials and the head of an air traffic control group says a worker was hurt when lightning struck BWI Airport, shutting down flight operations.

The Federal Aviation Administration said lightning struck the air traffic control tower at 2:21 p.m. Thursday. The FAA suspended arrivals and departures until about 4:45 p.m., according to a BWI spokesman.

John Dunkerly, president of the National Air Traffic Controllers Association, said that he had just left the tower when the lightning strike, which he said hit a runway, occurred. He said a traffic management coordinator who was turning on equipment in the tower was shocked when the electricity traveled to the tower.

Dunkerly says the worker was taken to a hospital. An FAA official said the worker did not appear to be seriously injured.

Authorities have ordered all residents of the town of Lyons, located north of Boulder, to leave this morning as deadly flooding worsened overnight as record rains continued in central Colorado.

The Boulder County Sheriff's Office said officials planed to evacuate the town of about 2,000 around daybreak, according to KDVR in Denver. The Colorado National Guard has been called into to help.

Torrential rain drenched parts of Colorado, washing away homes and causing at least two deaths as officials worked Thursday to evacuate towns and keep people out of the path of the rising water.

The National Weather Service described a "life-threatening situation" in an emergency message issued just after midnight local time for several areas around Boulder, where about 6.5 inches of rain fell in the last 24 hours, according to the National Weather Service.

The first death was reported near Jamestown, according to officials, and was thought to be because of a building collapse. The Colorado Springs Fire Department reported a second death on Thursday morning after a body was recovered near Interstate 25.

John Schulz , Public Information Officer of the Larimer County Sheriff's office in Colo., said a series of dams overflowed and one broke overnight, killing one, and threatening hundreds more.

Authorities found the second body while out patrolling in the I-25 area around 5:30 a.m. local time, Colorado Springs Fire Department spokeswoman Sunny Smaldino told NBC News affiliate KUSA.

Lyons - Flash flooding in Colorado has left two people dead and the widespread high waters are keeping search and rescue teams from reaching stranded residents and motorists in Boulder and nearby mountain communities as heavy rains hammered northern Colorado on Thursday.

The National Weather Service warned of an "extremely dangerous and life-threatening situation" throughout the region as the flooding forced people from their homes, canceled classes and led to mudslides and rockslides in some areas.

"Move to higher ground now. Act quickly to protect your life," the Weather Service warned in numerous bulletins that went out throughout the morning.

Where are all the hurricanes Al Gore, Bill McKibben, Joe Romm, and Brad Johnson say are supposed to happen due to global warming? Article includes most recent forecast from Klotzbach and Gray

Bloomberg News: August is about to end without an Atlantic hurricane for the first time since 2002, calling into question predictions of a more active storm season than normal.

Six tropical systems have formed in the Atlantic since the season began June 1 and none of them has grown to hurricane strength with winds of at least 74 miles (120 kilometers) per hour. Accumulated cyclone energy in the Atlantic, a measure of tropical power, is about 30 percent of where it normally would be, said Phil Klotzbach, lead author of Colorado State University's seasonal hurricane forecasts.

"At this point, I doubt that a super-active hurricane season will happen," Klotzbach said in an e-mail yesterday.

The most active part of the Atlantic season runs from Aug. 20 to about the first week of October. The statistical peak occurs on Sept. 10, according to the National Hurricane Center in Miami.

A huge waterspout has been spotted off the coast of the Croatian city of Dubrovnik.

Amateur footage captured by a passerby from a nearby cliff face shows a whirling column of air and water travelling across the ocean.

Funnels and waterspouts are caused by unstable weather conditions and are becoming increasingly common in this part of Adriatic Sea.