Public Information Statement National Weather Service HANFORD CA ...A new river forecast point to enhance Hydrologic Services in Yosemite National Park begins December 1st... The Happy Isles gage on the Merced River in Yosemite National Park will operate as an official river forecast point and will be added to the National Weather Service (NWS) Flood Warning Program on December 1, 2018. This will be implemented through a collaborated effort between the NWS San Joaquin Valley, the California-Nevada River Forecast Center (CNRFC), the United States Geological Survey (USGS) and the National Park Service (NPS). With this new capability, Yosemite National Park officials will have an improved resource to utilize during heavy rain and Spring snowmelt events to help make critical decisions along the Merced River within the park. The gage at Happy Isles, which is owned by the USGS, has been in existence since 1915. Happy Isles will become the second forecast point along the upper Merced River in Yosemite National Park, upstream from the current river forecast point at Pohono Bridge. The forecast information will be utilized to provide flood impacts and warnings along the upper Merced River. Information and services provided by the CNRFC of forecasted river stages at Happy Isles will assist emergency officials with their strategic planning to evacuate downstream areas that would be impacted by flooding. Part of the warning services program includes public accessible graphical forecasts from the CNRFC and the NWS San Joaquin Valley web pages. These graphical forecasts include observed river stage and flow data for the previous five day period from the USGS, forecast data for the next five days from the CNRFC, a description of documented impacts for the location, and a map of the gage. Additionally, the NWS San Joaquin Valley website will be updated hourly to include the latest river stages for Happy Isles. The forecast portion of these graphics will originate from the CNRFC hydrologic model and will be updated one to four times daily, based on river conditions. This is a great example of organizations working together for the improved safety and the protection of life and property of residents, tourists and campers within Yosemite National Park. Again, the Happy Isles stream gaging site will become an official river forecast point on December 1, 2018. Please contact Kevin Durfee (559-584-0583) or Cindy Matthews (916-979-3041) of the National Weather Service for any questions or feedback on the establishment of this new river forecast point.

November 2, 2018 - The Happy Isles gage on the upper Merced River in Yosemite National Park will officially become a river forecast point on Dec 1, 2018. NWS flood warnings issued for Happy Isles will help park officials decide when to evacuate downstream locations during heavy rain and Spring snowmelt events. This is a great example of organizations working together for the improved safety and life protection of residents, tourists, campers and hikers within Yosemite National Park.Source: NWS Hanford