Projected rainfall totals for Mariposa: 0.50" to 1.00"
Projected rainfall totals for Oakhurst: 0.50" to 1.00"
Projected rainfall totals for Yosemite Valley: 1.00" to 1.50"
March 18, 2021 - The National Weather Service Hanford Office reports a storm system will impact Central California this evening through Friday night.The majority of precipitation associated with this storm system will fall Friday.
Snow levels will start at around 6,000 feet this evening, before falling to about 5,000 feet Friday evening.
Area Forecast Discussion National Weather Service Hanford CA 401 AM PDT Thu Mar 18 2021 .SYNOPSIS... A warming trend is expected through Thursday. A trough of low pressure will pass through Northern California Thursday night and Friday. Precipitation associated with this trough of low pressure will trend lighter from northern areas to the southern locales in central California. Temperatures will be below seasonal values this weekend. Strong, gusty winds and increased chances of precipitation are possible in Central California early next week. && .DISCUSSION... A low pressure system originating from the Gulf of Alaska currently centered over the eastern Pacific at 37N 138W per current satellite imagery will continue moving eastward into the Pacific Northwest. The associated cold frontal boundary is draped southward and currently beginning to transit into northern California and will move into central California later this morning bringing increased clouds and a breezy conditions along with showers and moderate rainfall at times through this evening. Precipitation amounts will trend higher in the northern parts of the CWA and lower southward into Kings, Tulare, and Kern Counties. Storm totals for the San Joaquin Valley will run from about a third of an inch in the Merced area to less than a tenth in the southern parts of the SJV. Higher elevations will see greater accumulations with around 1.25 inches in the Yosemite area to less than a tenth of an inch in the far southern Sierra and Kern County mountains. Snow levels look to start out about 6000 feet later this morning and increase to almost 8000 feet by late evening today and hover around that elevation through Friday night. Snow amounts will mostly range from 2 to 6 inches in the Yosemite area above 6000 feet with higher amounts from 6 to 12 in the highest elevations with localized heavier amounts possible in the far northern parts of the Sierras near Yosemite. A winter weather advisory has been issued above 6000 feet from Sequoia National Park northward to Yosemite National Park from 11 AM today until 5 AM Saturday to address this threat. Mountain areas above 6000 feet from Fresno/Tulare county line southward will only see a trace to a couple inches of snowfall at most. Late Friday into Saturday the frontal boundary will transition to a more easterly to westerly orientation as the trough axis flattens out with the assoicated system weakening from a closed system to southerly moving hanging trough that will sit over central California. This will allow for unstable conditions and increased clouds to persist through Sunday. However, precipitation amounts will be minimal to non-existent. Any precipitation will be highly scattered and very light. Late Sunday the trough axis/frontal boundary will again begin moving southward and will once again increase light precipitation chances and breezy to gusty winds will be possible with the strongest winds in the pass areas and the Kern County mountains and desert areas. Weak ridging will move into the region on Monday giving us a break in precipitation and allow for a small warming trend to near normal levels. However, another system, this time an inside slider looks to move southward into the region but may skirt just eastward of the area and the main impact would only be increased clouds and winds. But, confidence is lower with the exact system placement and the devil is in the details, because if it tracks further westward it would create not only winds but increase the precipitation chances to the area. This will be monitored in subsequent shifts.
Source: NWS
