The National Weather Service has issued a Flood Warning for the Merced River at Pohono Bridge from late tonight until further notice or until the Warning is cancelled.
Rainfall forecast for today and early Saturday combined with warm temperatures is expected to bring sharp rises to high elevation basins where rain-on-snow will add additional runoff. Therefore, the heavy rainfall forecast for early Saturday is expected to cause sharp stream rises throughout the region.
At 8:00 AM Friday the stage was 5.5 feet. The river is forecast to fluctuate near 5.5 feet through late this morning then expected to rise above flood stage of 10 feet early tomorrow then forecast to rise to near 13 feet tomorrow morning with continued rise expected.
Potential Impacts include:
* Near 6.5 feet, the River is closed to rafters and flotation.
* Near 9.0 feet, Chapel Meadow (south side of river) and Cooks Meadow (north side of river) begins to experience overflow.
* Near 9.5 feet, Portion of Lower Pines Campground becomes flooded. Limited site-specific evacuations begin at Housekeeping Camp located along the south-facing bank of the Merced River (Upstream from Sentinel Bridge and downstream from Stoneman Bridge).
* Near 10.0 feet, Western portion of North Pines Campground located at the east end of Yosemite Valley between the confluence of the Merced River and Tenaya Creek begins to flood. Water rises to the base of the swinging bridge downstream from Chapel Meadow.
* Near 12.5 feet, Northside Drive and Southside Drive, which are the main roads in Yosemite Valley, become flooded and are closed to traffic.
Unlisted forecast points are expected to remain below monitor stage.
All those affected by river conditions should remain alert for rapid changes and for possible forecast revisions.
Additionally, the National Weather Service has issued a Flood Watch for the Mother Lode, the Sierra Nevada and the Northern San Joaquin Valley from this afternoon through Sunday morning.
Three to seven inches of total rainfall is expected in the Sierra Nevada. One to three inches of rain is likely in the Central Valley.
Snow levels will remain mostly above the 12,000 foot elevation.
Heavy rainfall, in addition to snow melt, will create excess runoff and bring a threat of localized flash flooding, mud slides, rock slides and debris flows.
Moderate rises will occur on mountain rivers, streams and some weirs. Stream and creek levels are expected to rise and could cause local flooding. Ponding on roads is also a possibility. Some roads may become impassable or become washed out.
A Flood Watch means there is a potential for flooding based on current forecasts. You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.