The heat wave officially begins and lingers into early next week

Posted at 4:44 PM, Jul 13, 2023

Interior temperatures have warmed this week but a larger jump in temperature took place today and it's just the beginning. Most of the interior of San Luis Obispo and Santa Barbara County spent the day in a heat advisory. This is the lower-level advisory relating to this heat wave.

The same area is elevated to an excessive heat warning Friday morning into Monday morning. The excessive heat warning is the highest elevation warning that can be issued relating to heat. In this case, it refers to not only the daytime highs reaching 100 to 110 degrees or more but also the concern that overnight lows may not offer much relief to some. The Santa Ynez Valley will enter a heat advisory Friday morning until Sunday at 10:00 PM. All the advisories are to heighten your awareness of the heat and urge you to take precautions against it not only for yourself but for others and for any animals you may tend to.


This heat wave inland is caused by a ridge of high pressure which is still amplifying over the western United States. The highest amplitude of the jet stream ridge takes place over the weekend and correspondingly we will see the highest temperatures.

It is important to note that not all locations will experience a heat wave. Beaches and near coastal valleys we'll still have some access to marine cooling though that cooling may diminish a little during the anticipated warmer weather inland. Coastal valleys will ultimately warm into the 80s to near 90 degrees though some coastal valleys will remain in the upper 70s with the South Coast of Santa Barbara County also seeing temperatures in the upper 70s and low 80s. Night and morning low clouds are possible in these areas and even if those clouds burn off or are mixed out submarine cooling will still take place. All these locations are places to beat the heat during this heat wave.


The ridge of high pressure over The West takes a dent from a trough moving into the Pacific Northwest early next week.

Wednesday and Thursday interior temperatures probably drop under 100 degrees but quickly return two hot temperatures to close the week as another heat wave is anticipated. The climate prediction center expects the second half of the month to be warmer than average.