Rain ahead of winter storm leads to flood watch
Before turning to sleet, ice and snow Friday night, enough rain is forecast to fall Thursday into Friday that the National Weather Service has issued a flood watch for the area.
The watch is in effect from 7 p.m. Thursday through Saturday afternoon. It covers all of southwestern Pennsylvania.
Rainfall is expected to start around 5 p.m. and last until mid-day Friday before changing to a wintry mix.
Up to 2 inches of rain, combined with melting snow from the warm temperatures, may result in localized flooding.
Rises from rainfall and snow melt will result in movement and break-ups of ice on area rivers and streams, which could lead to ice jams and flooding, the watch states.
However, a meteorologist said there is more of a concern for flooding on smaller streams and creeks, which could lead to localized water issues. There's not as much concern about river flooding.
With temperatures rising into the 60s, ice is dissipating and getting flushed out ahead of the rain.
Flood Watch issued for tonight into Saturday. 1.25-2' of rain expected, which when combined with snowmelt could cause localized issues. River ice will move/break up too, with possible ice jams. pic.twitter.com/hqkkdAjhl9— NWS Pittsburgh (@NWSPittsburgh) January 11, 2018
Ian McKelvey, operations specialist for the Allegheny River with the Army Corps of Engineers, said there isn't much concern about ice conditions on the Allegheny.
The river is "fairly clear" from the Highland Park Bridge up to Ford City. Ice is thicker above Ford City, but was melting and breaking up in the warm weather.
The ice has room to flow out, he said.
"We'll just continue to monitor it," he said. "Right now we're not too concerned about it."
A year ago, almost to the day, heavy rain north of Pittsburgh combined with snow melt to push the Allegheny River to near or over flood stage in several locations. There had been flooding in several Armstrong County communities, some roads were flooded and closed, and some basements flooded.
A flood watch means there is a potential for flooding. Those living in areas prone to flooding should be prepared to take action should flooding occur.
Brian C. Rittmeyer is a Tribune-Review staff writer. Reach him at 724-226-4701, firstname.lastname@example.org or on Twitter @BCRittmeyer.