[quote=Tin369] Is Rancho penesquitos really 10 degrees hotter than the coast?
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First, there’s really only a significant temperature difference when there’s a cool seabreeze. Which is most of the spring and summer and I’d say sometimes in the fall. On some days the marine layer goes all the way to the mountains and stays all day. On those days the temperature difference isn’t so great. Those days are pretty common in May and June (although not this year).
Penasquitos is a couple miles in width. So the very east parts of RP will be probably two degrees warmer than the western parts.
And “the coast,” temperature wise, really means right at the coast. Within, maybe, a quarter mile. That first mile is the biggest, then the gradient shallows (but is still significant). There are lots of days in the summer when the coast doesn’t get above 68.
But, yes, I would guess that the very eastern parts of RP average about 8 or 10 degrees hotter than the immediate coast in the summer (on days when the marine layer doesn’t cover RP all day). The western parts a bit less.
This is all just my (fairly close) observations over the years, but others might have other information.
Edit:
RP is actually about 4 miles wide. The closest part of it is about 5 1/2 miles from the ocean and the farthest about 9 1/2 miles. But the bulk of it is 7-9 miles from the ocean. Those are the areas I was using. But if you live in the very western part, you might only be 5 to 7 degrees warmer than the coast.