Total for this storm: 14.71 (single-storm record)
Total for Sept. 2013: 14.74 (new record for month)
Total for 2013: 27.70
Total for 24 hours ending 6 p.m. Fri.: 2.44
Highest reading for 24-hour period during this storm: 9.08 (6 p.m. Wed. to 6 p.m. Thurs.
Prev. record for one storm: 7.37 in May 5-8, 1969
Prev. record for Sept.: 5.50 in 1940
Record for one year: 29.93 in 1995
Prev. record for any single month: 9.59 in May 1995
Source: meteorologist Matt Kelsch
The Boulder area can breathe a sigh of relief under sunnier and drier skies Saturday, but that respite will be followed by a return to wetter and cooler conditions Sunday.
"It looks like there is a chance of some heavy rain Sunday, and a continued risk of flash flooding. And then we finally dry out on Monday," said National Weather Service meteorologist Jim Kalina.
That would be rain that absolutely is not needed, after Boulder -- between Monday evening and 6 p.m. Friday -- had registered a record-shattering 14.71 inches of rain. In the 24-hour period ending 6 p.m. Friday, 2.44 inches fell.
"I know 2.44 doesn't sound like a lot, but that's an impressive one-day total, even though it pales in comparison to the last few days," said meteorologist Matt Kelsch, who noted that this week's rain event would have been remarkable even in New Orleans.
Kalina said Saturday poses a 30 percent chance of showers, with temperatures in the mid- to upper 80s and the rain possibility ticking up to 40 percent into the evening.
Then comes an overnight cold front, according to forecasters, which will pull temperatures back down into the mid-60s for Sunday. That will bring with it a 60 percent chance of rain fueled by more southerly moisture in the daytime, then decreasing to a 50 percent likelihood in the evening.
And although Saturday night's chance of showers is lower, Kalina said, "We could still have some isolated areas of heavy rain, and if we get the heavy rain in certain spots, we could get some more flooding issues."
Even as Boulder starts seeing decreased rain possibilities in its forecast, it is still not cause to completely relax.
"We have saturated ground in a lot of places; we have rivers and creeks that are over their banks," said National Weather Service meteorologist Kari Bowen. "We can't take a whole lot of rain without more flooding and flash-flooding potential. If we feel the need to put out a warning, we will do that."
A U.S. Geological Survey expert Thursday declared the event for Boulder has a one-in-100 chance of occurring in any given year. That translates to what many people term a 100-year flood, although the USGS no longer uses that term.
In fact, a USGS gauge on Boulder Creek at North 75th Street on Friday morning measured a flow rate even higher than that which the 100-year ranking was based on.
The flow Friday morning was measured at 5,200 cubic feet per second, substantially higher than the 4,500 cfs rate previously measured. By 4:15 p.m. Friday, it had slipped back down to 4,460 cfs.
That gauge has only been in place for 26 years, but its previous highest flow rate ever measured was 2,050 in May 2003.
"We're looking at levels in Boulder Creek which we probably have not seen since the late 1930s," said Robert Kimbrough, associate director of the USGS Colorado Water Science Center. He did note, however, that Boulder Creek did not have a gauge that the USGS can depend on from 1955 to 1979.
A final determination on whether the ranking of the flood of 2013 will be adjusted, potentially to a status even rarer than one in 100, will take some time. That is, in part, due to the fact that some USGS gauges -- including one on the St. Vrain Creek and another on the Big Thompson River in Loveland -- were washed away or at least stopped working.
"When we lose a gauge, that means we're going to have to go in with surveying equipment and compute a peak discharge for the event based on surveying and examining high water marks left by the flood crest," Kimbrough said. "That's a labor-intensive exercise, and that takes a minimum of a couple of weeks to collect that information and come up with a peak flow value at that site."
Contact Camera Staff Writer Charlie Brennan at 303-473-1327 or firstname.lastname@example.org.