Red Bluff is not arid and hit 121°F in August 1981. I could see a black swan heat event getting to 125-127°F in the Sacramento Valley.
It’s an interesting paradox where places like Lytton, Pasco, and Redding being in the temperate zone actually increases their upper end heat potential in heatwaves in terms of departure from average compared to a subtropical location like Palm Springs or Lake Havasu.
Yesterday, the city of Hami, China had a max temp of 44.7°C and a low temp of 36.7°C, the highest low temp ever recorded in China.
Average July low there is 19.3°C only. So a really extreme +17.4°C anomaly. And also the hottest night ever recorded ANYWHERE ON EARTH above 40°N and 700 m.
Turpan also tied its July record with 49.1°C.