I'm behind Lake Morena. It's almost full and I'm on the road hearing 6 to 10 inches of rain. 9 inches is our average annual rainfall. They say it's been 84 years since we've had a storm that size. The lower lakes are full too. I saw them all spill over in The 70's. Sweet Water Dam broke in 1910 which means the concrete's over 100 years old. They were supposed to rework Lake Morena Dam beginning 2018 but have procrastinated. It was down to 33% due to the drought then for the sake of some sort of sporting event at Otay Lakes the City with water rights drained 30% of the 33% full Lake Morena. At that time it was a brilliant opportunity for the County to easily fix the damn as scheduled. Anyway, I've been told mission valley has had water rise halfway up the side of Mission Valley. I guarantee you it will flood coz it often does. How much remains to be seen. The odds are good the lakes will fill faster than the dam spillway can let the water out so they all have potential to overflow. Most people don't know the rivers ran wild through San Diego making much of it uninhabitable prior to the Army Core of Engineers building the Lake Morena reservoir along with a lot of concrete channels in key places coming down the mountain. That was built in the late 1800's. Ever since the Katrina fiasco I've been watching the same recipe for disaster being ignored so stay far away from Mission Valley and an obviously low corridors if any of the dams get close to the top and learn to swim ;-) :-D
Of course they're also terrible at predicting these big storms so watch it Peter out on the way., LOL. They usually come as a surprise.