November 29, 2018 - The National Weather Service Hanford office reports a few severe thunderstorms in Mariposa County, Madera County and the Central Valley are possible today.

  Area Forecast Discussion 
  National Weather Service San Joaquin Valley - Hanford CA 
  423 AM PST Thu Nov 29 2018 
   
  .SYNOPSIS... 
  Gusty southeasterly winds will impact the northwestern portion of 
  the San Joaquin Valley this morning. Heavy snow is expected in  
  the higher elevations of the Sierra Nevada today into tonight,  
  while moderate to heavy rain at times will fall elsewhere.  
  Mud/rockslides or debris flow is likely in portions of the Sierra  
  Nevada Foothills today and tonight. Isolated thunderstorms are  
  possible today and this evening.  
   
  && 
   
  .DISCUSSION... 
  A myriad of issues are on the table this morning as an Eastern 
  Pacific storm system approaches Central California. Inflow into 
  this low pressure system is evident in the northwestern portion  
  of the San Joaquin Valley, where about a half dozen reporting  
  stations in Mariposa and Merced Counties are observing  
  southeasterly wind gusts in excess of 35 miles per hour. A Wind  
  Advisory is in effect for this area until noon. As the 
  aforementioned storm system pushes eastward through the northern 
  half of California, gusty west to northwest winds will develop in 
  the Indian Wells Valley and Kern County mountains and desert. Wind 
  Advisories are in effect for those areas until 9 pm PST. The Wind 
  Advisory for the Kern County mountains and desert will likely need 
  to be extended beyond that time.  
   
  Hydrologic concerns exist as well. Heavy rainfall moving over the 
  Ferguson burn scar this morning has resulted in the issuance of a 
  Flash Flood Warning. Around an additional foot of snow is expected 
  in the higher elevations of the Sierra Nevada today into tonight. 
  A Winter Storm Warning remains in effect for this area. A Flash  
  Flood Watch remains in effect for the Sierra Nevada Foothills.  
  Mid-level lapse rates should steepen and cooling should take place 
  aloft today. Atmospheric instability may be sufficient for 
  isolated thunderstorms to develop in the San Joaquin Valley and  
  in the Sierra Nevada Foothills today and this evening.  
   
  An upper-level area of low pressure will approach the Pacific 
  Northwest Friday, before moving onshore Friday night. This area  
  of low pressure aloft will open into a trough of low pressure and 
  dig southeastward into northwestern Nevada Saturday. A more due  
  eastward trajectory is expected through the Great Basin Saturday  
  night. A ridge of high pressure between longitude 140 West and 130 
  West will approach California late in the upcoming weekend into  
  early next week. Another Eastern Pacific storm system may begin to 
  impact California by the middle of next week.  
   

Source: NWS