When it comes to heat, it's all about location
When I moved up from the Bay Area several years ago, I was shocked that the hottest part of the day was around 5 p.m. In the Bay Area, the hottest time of the day was around 2 p.m. I know the fog plays a role in moderating temperatures down there, but the fog didn’t always blow in, and temperatures usually subsided by mid-afternoon. What’s going on around here?
— Tim M., Medford
Actually, Tim, there’s a pretty easy explanation for the difference in weather between Medford and the Bay Area, according to the National Weather Service.
The Bay Area is right next to one of the biggest air conditioners in the world, the Pacific Ocean.
Even if the fog doesn’t roll in, an afternoon sea breeze cools things off substantially. Just go out to the Oregon Coast and you’ll see the same sort of breeze.
The land heats up faster than the ocean, creating low-pressure compared to the coast in the Bay Area. The relatively higher pressure over the ocean and cooler temperatures are sucked into the lower pressure.
Unfortunately, we’re too far inland with many more mountains in between to take advantage of this natural air-conditioning system.
According to the National Weather Service, this cooling effect can be felt in some big cities such as Dallas, Texas. Because it’s relatively flat from Dallas to the Gulf, the cooler air makes its way inland hitting the city late at night, even though the city is far away from the sea.
The Medford area is subject to other forces of nature because of our location and the surrounding topography.
For instance, this week, we started seeing smoke in the valley from fires burning in Northern California.
Because of our location, our summers are typically hot and dry, with the occasional thunderstorm.
Tim, you better learn to love the summer heat in the Rogue Valley. On the other hand, our winters are generally much colder than the Bay Area.
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