May 9, 2019 - The National Weather Service reports a Winter Weather Advisory is in effect for the Southern Sierra Nevada from Yosemite to south of Sequoia National Park above 8,000 feet from 11:00 A.M. this morning through 11:00 P.M. Friday.
Motorists should anticipate additional snow covered and closed roads above 8,000 feet.
If you plan to travel in the mountains, remember to carry tire chains, plenty of food, a good deal of water, and warm clothing in your vehicle.
Visitors to the Sierra backcountry can expect adverse weather conditions with the additional accumulating snowfall and gusty winds.
For information on road conditions, including closures or delays, call Caltrans at 1-800-427-7623 or visit http://www.dot.ca.gov/cgi-bin/roads.cgi.
Area Forecast Discussion National Weather Service San Joaquin Valley - Hanford CA 345 AM PDT Thu May 9 2019 .SYNOPSIS...A low pressure system will drop southward from the northern Rocky Mountain region into our area by this evening and bring unsettled showery conditions to our area by this afternoon and much cooler temperatures by Friday. Thunderstorms will be possible across our area today and again on Friday. && .DISCUSSION...Upper shortwave currently dropping southward through southern NV has brought some mid/high clouds to our area overnight. These clouds are continuing to push southward and will be out of our area by later this morning as the shortwave moves into northern AZ. A dry northerly flow will prevail over our area today and once again a mostly sunny morning is in store for our area today and temperatures will be near seasonal normals. Meanwhile, an upper low center over the northern Rocky Mountain region is progged to drop southwest toward central CA today. The approaching low will destabilize the atmosphere over our area by late this afternoon providing for increased chances across the mountains and Kern Deserts by this afternoon and into the San Joaquin Valley by this evening. Isolated thunderstorms will be possible throughout our area by late this afternoon as the 06Z WRF is indicating LI`s between -4 DEG C and -1 DEG C and CAPES between 800-1200 J/KG across the San Joaquin Valley with higher amounts over the mountains. RH progs are indicating that this low is moisture deficient and any precipitation over our area will be more dependent on afternoon and evening convection. QPF amounts will be very difficult to pinpoint due to the convective nature of the precipitation that is expected, but locally heavy rainfall is possible in stronger thunderstorms this evening. The low is progged to move over our area tonight then drop southwest to off the Socal coast on Friday providing for increased clouds and unseasonably cool temepratures on Friday as well as a continuation of unsettled weather conditions through Friday with the likelihood of showers remaining high tonight and Friday. Isolated thunderstorms will once again be possible throughout our area Friday afternoon and evening. Any thunderstorms that develop today and Friday have the potential to produce heavy rain, dangerous lightning, gusty and erratic winds, as well as small hail. In addition, snow showers will be likely above 8000 feet in the Southern Sierra Nevada. Have issued a Winter Weather Advisory for elevations above 8000 feet from midday today through Friday evening as winter weather becomes less frequent this time of the year. Many locations above 8000 feet are expected to pick up between 4 and 8 inches of now snow by Friday evening with locally higher amounts possible near ridge tops. Below the snow line, hydrological concerns might become an issue in the southern Sierra Nevada and adjacent foothills tonight and Friday as heavier showers could combine with snowmelt runoff. The low is progged to drift eastward into northern Baja by Saturday, but the models often have problems with cutoff lows so am not very confident of that happening. The upper flow will be east to northeast this weekend, but wrap around moisture will provide for a continuation of showery weather over the mountains and chances of showers over the Kern County Deserts and southern and eastern portions of the San Joaquin Valley. The medium range models are indicating the low moving east along the US/Mexico border on Sunday and Monday which would give way to a clearing, drying and warming trend. However, am not too confident on that happening as cut off lows seem to have a mind of their own. Am trending temperatures upward, cloud cover downward and showers less prevalent each day Sunday through Tuesday, but confidence is low. A Pacific trough is progged to reach the western Conus coast by the middle of next week which may bring another round of cooler temperatures and unsettled weather to our area.Source: NWS
