UPDATE | 3:25 a.m. — Rainfall ended in Phillips County and a station southeast of Holyoke recorded 8.04 inches of rain and about 3.26 between just 5 and 6 p.m. The radar estimated about 9 inches in spots nearby, according to the National Weather Service.
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DENVER — The National Weather Service has reported 4 to 8 inches of rain has fallen in Phillips County, and more rain is expected overnight.
A flash flood warning expired at 10:45 p.m. in Phillips County, but NWS reissued the warning until 3 a.m. An additional 2 inches could fall overnight, further exacerbating any flooding that has already occurred.
NWS said the most significant impact is in the southeast portion of the county.
There are reports of water running over the road on Highway 6 east of Holyoke near the Colorado/Nebraska border.
A considerable Flash Flood Warning was reissued for Phillips County. 4-8" of rain have already fallen with up to 2" of additional rainfall possible. Turn around, don't drown! #COwx https://t.co/s7iRmBgYMz
— NWS Boulder (@NWSBoulder) August 20, 2021
Yuma County has received one to three inches of rain, and a flash flood warning remains in effect until 12:45 a.m. Friday. NWS anticipates Highway 385 between mile markers 257 and 269 could be affected by flash flooding.
NWS warned drivers to be careful, especially because it can be difficult to identify hazardous conditions at night. It's possible some roads may wash out, NWS said.