The Rex Block that has been presenting weather disturbances from moving into our region, will break down today. This is going to change the weather in the incoming days, bringing more cloud cover to Northern California. At this point, it looks like enough moisture is going to wrap around the southern portion of the Rex Block – an area of low pressure, and allow for thunderstorm development Thursday and Friday afternoons. This will be isolated and just over Siskiyou and Modoc Counties.
The heat will continue into the weekend until a closed low begins shifting eastward. By Saturday, cloud cover, moisture and instability will all be on the rise. Isolated thunderstorms will then become a threat for Southern Oregon through Sunday.
This will mark the start of a new weather pattern, a wetter and cooler transition from what’s in place now. Afternoon highs are expected to drop below normal—much different from the 10-15 degree above average temperatures we are seeing currently!
Meteorologist Alyssa Caroprese