Includes Eastern Mariposa and Madera Counties and Yosemite National Park
Small hail and wind gusts near 40 miles per hour are a couple of hazards associated with strong thunderstorms.
In addition to dangerous cloud to ground lightning strikes, any thunderstorm can produce intense rainfall rates, leading to localized flooding.
Area Forecast Discussion National Weather Service Hanford CA 124 AM PDT Sun May 16 2021 .SYNOPSIS... Low pressure will move southeastward across the region today with showers and thunderstorms a good bet over the Sierra and Indian Wells Valley this afternoon. As the low moves east into the Four Corners region on Monday, left over moisture over the Sierra will allow for some additional afternoon showers and thunderstorms. Temperatures will be below normal today however a warming trend will begin Monday and Tuesday as high pressure becomes reestablished over the West. Another trough of low pressure will bring cooling temperatures beginning Wednesday with below normal values expected later in the week. && .DISCUSSION... Nicely formed area of low pressure is well noted on water vapor imagery spinning around its center over the San Joaquin Valley early this morning. Around the periphery of the low radar shows some snow showers over the Sierra crest from the northern edge of Kings Canyon Park to Yosemite. This low will be the main driving factor today for the development of showers and thunderstorms later today as plenty of colder air aloft will bring instability to the Sierra. Forecast models move the low pressure center southeast across Kern County later this morning and this afternoon and the resulting northerly flow (and the best instability due to cold air aloft) behind the low will likely move and/or form thunderstorms across the Indian Wells Valley this afternoon and early evening. Model forecast precipitation totals will range from zero to as much as 0.50" in heavier showers and thunderstorms. Again most areas in the Sierra and desert won`t receive measurable precipitation however a some will. The remainder of the area will have mainly partly cloudy conditions with much remaining at or just below normal. On Monday, models are in good agreement in moving the low quickly east across Arizona with heights making a quick rise as a short wave ridge edges in from the west. Flow into the Sierra will be from a northerly direction. This will allow for some additional, but not nearly as widespread as today, showers and thunderstorms with the remainder of the area remaining dry and warming up a few degrees. Continuing the warm up, on Tuesday the short wave ridge reaches its maximum heights over Central California Interior thus the warmest day of the upcoming week will occur. No real extremes of heat this week as values on Tuesday will be just slightly above normal. Wednesday will mark the beginning of another cool down as a trough of low pressure pushes into the Pacific Northwest and then on Thursday and Friday a robust area of low pressure moves into the north state and Great Basin. Central California Interior should remain dry, however a cooler than normal period of weather will be the result.Source: NWS
