Parked vehicles sit partially submerged near Greeley, Colorado, on Saturday, September 14. Flooding in Colorado has washed away roads and bridges and flooded homes. Authorities warned more rain was on the way, threatening more flooding. At least four people have been killed and hundreds are unaccounted for, officials say. 
Brother and sister Eli and Noe Sura play in the mud around their Boulder, Colorado, home on September 14. 
A National Guardsman stands at South Main and Missouri streets in Longmont, Colorado, on September 14. 
Flood waters swamp Longmont, Colorado, on September 14. 
Dave Jackson closes a mailbox with his foot after delivering the mail to a home surrounded by water from the flooded Cheyenne Creek in Colorado Springs, Colorado, on Friday, September 13. 
Rescue personnel search for flood victims near Fort Collins, Colorado, on September 13. 
Chris Rodes helps Fred Rob salvage a friend's belongings after floods left homes and infrastructure in a shambles in Lyons, Colorado, on September 13. 
During a break in the rain, a woman walks over a footbridge past the raging Boulder Creek in Boulder on September 13. Boulder County is one of the hardest-hit areas. 
Suzanne Sophocles hugs her dogs after they were rescued from her flooded home on September 13 in Boulder. Thousands of people stranded by the flood waters in Colorado were finally able to come down by trucks and helicopters, two days after seemingly endless rain turned normally scenic rivers and creeks into coffee-colored rapids that wrecked scores of roads and wiped out neighborhoods. 
Residents look at the flood damage along Topaz Street in Boulder, on September 13. 
Will Pitner gets rescued by emergency workers and neighbor Jeff Writer, on September 13 after he spent a night trapped outside above his home at the base of Boulder Canyon. 
Water rushes where a bridge collapsed in a flash flood in Lyons, on September 13. 
A man runs through the flood waters in a yard in Boulder on September 13. 
Topaz Street resident Jake Koplen stands at the edge of his driveway after the street in front of his home was washed away in Boulder on September 13. 
Brother and sister Patrick Tinsley and Mary Kerns head to Boulder from the mountain community of Magnolia, Colorado, on September 13. 
Samantha Kinzig of Longmont, Colorado, and her 5-year-old daughter Isabel take a closer look at the damaged bridge on Weld County Road 1 on September 13. 
A rubber ducky floats down Ninth Street alongside North Boulder Park in Boulder, on Thursday, September 12. 
Highway 7 is completely blown out from the South St. Vrain River as a torrent of raging water rips through it about 12 miles west of Lyons on September 12. 
A woman looks at the flooded Boulder Creek on September 12. 
Three vehicles crashed into a creek after the road washed out from beneath them in Broomfield, Colorado, on September 12. Three people were rescued. 
Nicky Toor, 15, floats on the flooded lawn of North Boulder Park in Boulder on September 12. 
Joey Schusler rides through flooded Canyon Boulevard in Boulder, on September 12. 
Residents view a road washed out by a torrent of water after overnight flash flooding near Left Hand Canyon, Colorado, on September 12. 
A city worker talks on his phone while surveying high water levels from Boulder Creek after flash flooding in downtown Boulder, Colorado, on September 12. 
Flash flood waters rush over a walking path in downtown Boulder on September 12. 
A police officer blocks off a road in Boulder on September 12. 
A man walks past the swelled Boulder Creek in Boulder on September 12. 
People stand at the edge of floodwaters in Boulder on September 12. 
A dive rescue team moves toward floodwaters in Boulder on September 12. 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
- NEW: Official: Clouds could hamper rescue efforts
- Boulder spared Saturday evening but faces rain Sunday
- Sheriff says authorities should be "realistic" about the chances the death toll will rise
- Missing woman is presumed dead, in addition to four confirmed dead
Are you there? Share photos and video if you can do so safely.
Boulder, Colorado (CNN) -- Colorado residents are keeping a wary eye on the sky as more rain is forecast for Sunday. As dawn broke, officials worried about continued rescue operations.
"We're going to be in for some steady rain over the next 12 hours," said Kim Kobel, a spokesperson for Boulder's Office of Emergency Management. It shouldn't total more than 1 to 2 inches though. "So that's the good news," Kobel said.
Still, authorities worry that any additional water on ground that's already soaked by up to 15 inches of rain will cause more flooding and dislodge mud and debris. Also, the omnipresent clouds pose a problem for aerial rescue efforts. "It's unlikely at this point that we'll be able to reach those who are stranded in the hard-to-reach areas," Kobel said.
Hundreds unaccounted for
At least four deaths have been blamed on the flooding, and a fifth person is presumed dead. More than 500 were unaccounted for, although authorities cautioned that designation included people who simply have not yet contacted concerned relatives elsewhere.
Members of the Colorado National Guard help Boulder County authorities evacuate residents of Lyons, Colorado, to Longmont, Colorado, on Friday, September 13. Flooding has hit the area hard, washing out roads, damaging bridges and destroying homes. 
The guardsmen are using Light Medium Tactical Vehicles, or LMTVs, which can transport about 16 people with luggage, to assist the evacuation. The LMTVs can navigate through rubble and flooded areas that otherwise could not be reached by rescue personnel. 
Dick and LaRue Vodime, temporary residents of Lyons, witness some of the destruction from the floods as they are evacuated to Longmont on September 13. 
Colorado Army National Guard Sgt. David Wilson carries Ezra Villa while escorting Thomas Walter and Melinda Villa to the flood evacuation area in Lyons on September 13. 
Residents ride in the back of an LMTV while being evacuated to Longmont on September 13. 
A Colorado Army National Guard helicopter takes off from the the Boulder Municipal Airport in Boulder, Colorado, on September 13. 
Guardsmen help residents and their pets off a Colorado National Guard Chinook helicopter at the Boulder Municipal Airport on September 13. 
Colorado National Guardsmen assist residents in unincorporated areas of Boulder County, Colorado. Residents were evacuating the area on Thursday, September 12. 
The guardsmen brought in high-clearance vehicles to take people out of the flooded areas. 
People, as well as pets, were loaded onto National Guard vehicles. 
The rains sent virtually every waterway in Boulder County coursing out of its banks, and massive water flows washed away roads and bridges, flooded homes and stressed numerous other bridges. 
Authorities reported between 25 and 30 roads were closed as of Thursday afternoon in Boulder County. Some of them had been washed out entirely. 
Friday's forecast calls for three more days of rain for the area. 
1
2
3
4
5
6
7
8
9
10
11
12
13
National Guard evacuates flood victims 
Colorado residents battle flooding 
Floods pose threat for first responders 
Colorado flooding turns deadly Elected officials were looking past the crisis to plan the recovery.
Gov. John Hickenlooper said he spoke by phone with U.S. Transportation Secretary Anthony Foxx, who "was adamant that the $5 million that was released Friday was just the beginning" of federal assistance.
"We're going to come back and rebuild better than it was before," the governor said.
Hickenlooper said experts from Vermont will arrive next week to share lessons about improved road-building learned in the wake of Hurricane Irene.
Damage worth millions
Boulder County alone will need an estimated $150 million to repair 100 to 150 miles of roadway and 20 to 30 bridges, county transportation director George Gerstle said. The repair bill will be "10 to 15 times our annual budget," he said.
A helicopter surveillance mission Saturday carrying Hickenlooper and members of Colorado's congressional delegation was diverted twice to pick up people waving to be rescued.
After the officials' delayed arrival at a Boulder airport, U.S. Sen. Mark Udall promised a bipartisan push in Congress for federal aid for flood recovery. "That dog and the cat and those seven people on those two helicopters didn't ask us whether we were Democrats or Republicans," Udall said.
President Barack Obama signed a major disaster declaration for Colorado on Sunday and ordered federal aid to supplement state and local recovery efforts in Boulder County.
More rain
Some storms appeared Saturday slightly east of the most flood-damaged areas, pounding southeast Denver with 1.73 inches of rain in less than 30 minutes.
But skies were clear for much of the day elsewhere, allowing rescues and a more complete count of those not yet located.
The Larimer County sheriff's office said that about 350 people were unaccounted for in the county. That number jumped sharply Saturday afternoon as rescuers reached more empty homes, even though authorities believe those residents got to safety.
In neighboring Boulder County, 231 people were on the "unaccounted for" list as of 7 p.m., said Gabrielle Boerkircher, spokeswoman for the county Office of Emergency Management. She said that number was fluctuating as some people were found safe even as the county received new requests to locate people.
Death toll may rise
Boulder County Sheriff Joe Pelle said authorities have to be "realistic" about the chances that the death toll will rise as rescuers penetrate farther into isolated areas.
No new deaths were confirmed Saturday, but Larimer County officials said a 60-year-old woman was presumed dead after witnesses saw her being swept away by floodwaters that demolished her home. Neighbors tried unsuccessfully to rescue the woman, said Nick Christensen, executive officer of the sheriff's office. Her body had not been recovered.
Teens swept away
The four confirmed deaths included a man and a woman, both 19, who were swept away after leaving their car Thursday in Boulder County. Authorities said the woman left the car first, and the man jumped out to try to save her. Authorities recovered both bodies.
Another body was found in a collapsed home in Jamestown in the same county. Rescuers recovered another body on a roadway in Colorado Springs in El Paso County.
CNN's David Simpson reported and wrote from Atlanta; Nick Valencia reported from Longmont, Colorado. George Howell reported from Boulder. Ana Cabrera reported from Lyons. CNN's Jack Hannah, Janet DiGiacomo, John Branch and Emma Lacey-Bordeaux contributed to this report.
