San Diegans are feeling the heat this week as temperatures soar to record highs in the Coachella Valley and surrounding areas. According to NWS San Diego, the afternoon highs are expected to reach near 110°, approximately 5 degrees above the usual for this time of year. The extended forecast suggests slight cooling on the horizon through Friday, with an uptick in night and morning coastal low clouds.

It's so hot, it's the heat 🌡️ 🪭

Here's what you can expect today, Coachella Valley 🔽 Highs will reach near 110° by the afternoon, about 5 degrees above normal for this time of year. #CAwx pic.twitter.com/hhUHKcsTkD

— NWS San Diego (@NWSSanDiego) June 26, 2024

A "weak coastal eddy" is prompting these low clouds to become more widespread, creeping further into the valleys as the weekend approaches. National Weather Service San Diego reports that while the coast and valleys will drop a few degrees today, the general cooling trend will persist into Friday and some drying late in the week.

However, the reprieve fades this coming weekend, leading to a scorching forecast. "High temperatures will warm for Saturday and Sunday with Sunday high temperatures around 5 to locally 10 degrees above average, to around 115 in the lower deserts and around 100 for the far inland valleys," NWS San Diego stated. Given the expected dryness and resultant cooler overnight temperatures, the heat risk for the deserts may ease slightly, potentially staying just below Excessive Heat Warning criteria for the tail end of the week.

But, as temperatures climb over the weekend, excessive heat is predicted to return to the desert regions on Sunday and could persist into the following week. This trend of elevated warmth corresponds to an interesting note regarding precipitable water values, which have recently soared to near-record heights for June. The climatological records, dating back to 1956, had been challenged with soundings from San Diego showing "PW values of 1.7, 1.7, 1.69, 1.68, and 1.65 inches," a marked increase in humidity that maintains warmer overnight temperatures. In fact, "over the past three days, there have been 28 daily records tied or broken for warmest low temperature," according to NWS San Diego's analysis.