Friday was the hottest day of 2026 so far in many places in the San Joaquin Valley, but this weekend should be just a little less hot – subtropical moisture will be moving in, bringing us clouds and possibly even a shower or thunderstorm. That moisture is part of the North American Monsoon, the weather pattern that brings Summer thunderstorms to the Desert Southwest, and often gets a boost from a developing El Niño – like the one we have brewing in the Pacific right now.
Clouds should stream into California Saturday afternoon and night, and could lead to a brief shower or even thunderstorm by Sunday afternoon and Monday. Unfortunately, dry lightning will also be a threat – those are thunderstorms without the rain – so fire danger will be high in the Sierra Nevada.
A warmer Pacific Ocean and Gulf of California can lead to an increase in Pacific hurricanes and Summer moisture surges into Southern California, and the Pacific continues to warm as El Niño continues to develop. The Climate Prediction Center is now giving this upcoming El Niño an 81% chance of being a Very Strong (or “Super”) one.…