Temps push down the next few days before another inland heat spike

Avila Beach with marine clouds
Posted at 4:53 PM, Jul 11, 2022

Marine clouds near the coast will be a big factor over the next few days as temps look to cool, especially inland. There are several key factors this time of year: marine depth, wind speed, and wind direction.

Marine depth only references how much vertical extent there is to cool marine air. Due to local topography, a marine layer depth of more than 1500 feet is important in that it allows more cool air to get into the interior valleys. If the marine layer is lower than that inland valleys temps get hot.

The latter was the case over the weekend, but Tuesday and Wednesday will likely see some big cooling inland with improved depth to the marine layer.

At the coast, the other factors are more important. Winds have slowed quite a bit. This reduces the rate that marine clouds mix out. When you know the winds are lighter and weakly onshore you can expect some stubborn clearing. And remember that clouds clearing doesn't necessarily mean warm weather, marine layer is often co-mingled with marine clouds. You can have the first without the second. I expect beaches to be in the 60s the next few days with some stubborn clearing, perhaps incomplete. Coastal valleys likely see early clouds with clearing but will stay cool in the lower 70s. Inland temps will drop into the 80s and lower 90s.

This cooler weather doesn't last long. Inland temps quickly shoot back into the triple digits Thursday to Sunday (and perhaps even next Monday). A trough in the jet stream is the reason we'll see improved marine depth but it lifts out later in the week and a heat dome over the Central U.S. edges west to crank inland temps. A little wamrer at the coastal valleys as well but just by 5 degrees or so. Beaches remain in the 60s due to ample marine presence.

The 8-14 day outlook from the Climate Prediction Center offers some hope for interior areas, the outlook is for roughly average heat (which is still 90+). Long runs of extreme heat would be a concern with drought conditions and also elevated fire risk.