Wednesday forecast for San Joaquin Valley: Hot with a cooldown soon to come
Today’s forecast: Another average-to-hot day
We said it yesterday: Wednesday will be a repeat of Tuesday with high temps into the 90s for the Central Valley. For Fresno and areas further south, temps in some spots will rise again into the triple digits. The temps in the Modesto area are close to average for this time of year, and slightly above average for Fresno, so nothing out of the ordinary.
But ordinary never lasts forever. As we have been previewing, a strong trough is developing over the Gulf of Alaska that will push into the western U.S. over the coming days with cooler temps, occasional clouds, and generally unsettled weather. More on that in a moment, but here is your forecast for the next two days ahead to round out your work week:
Fresno: High temps may actually be a slight bit cooler than yesterday thanks to higher pressure already backing off just a tad. Still the numbers will be marginal. Expect another warm morning with temps nearing the 90s by lunchtime and into the upper 90s soon after. Some spots in the San Joaquin Valley will breach 100 degrees. A touch cooler in the mid-60s overnight and for Thursday morning, but Thursday is otherwise a repeat of Wednesday.
Modesto: After a morning in the low 60s, temps will rise in the afternoon again to the mid-90s. The evening Delta breeze, just like in Sacramento, will be palpable. Thursday is a touch cooler with highs closer to 93 degrees, but the real change arrives this weekend.
Sacramento: High temps return to the low to mid-90s again today, with folks closer to Folsom feeling temps closer to 95 and those in Sacramento closer to 92. For planning purposes, just call it another June day. The evening Delta breeze will again be decent, so you can look forward to temps quickly backing off as the sun sets. Thursday is a touch cooler still, and don’t be surprised to see some clouds approaching Thursday evening — they herald the cooler weekend on the way.
Friday and the weekend: cooler temps and occasional shade arrive
About the cooler weather to come: It helps to compare our baseline now versus where we will be this weekend. Currently, our upper atmosphere, at the altitude where planes fly, is dominated by high pressure across the western and southwest United States. This high pressure “ridge” promotes stability, sunny skies and hot temps.
Between now and Saturday, a “trough” of lower pressure slides in from the Gulf of Alaska and parks over the Pacific Northwest for the weekend. For folks in Oregon and Washington, this means much colder temperatures alongside occasional clouds and showers. For California, it first means a brief injection of clouds across the northern half of the state and even a few stray showers here and there, alongside cooler temperatures and gusty winds.
Watch for clouds passing by Friday morning through the early afternoon — that is a cold front that marks the arrival of our cooler weekend. Along the front there will likely even be a few small and brief rain showers for folks in Sacramento and further north. High temps in Sacramento will dip into the mid-80s on Friday and into the low 80s on Saturday.
As the trough continues to deepen over the weekend, you might find it a bit breezy for whatever outdoor plans you have by then. It won’t be outright windy, but just enough that to be noticed. This will be especially true for the coast and the mountains, where wind gusts could exceed 30 mph. Wind gusts through the weekend, and a prolonged north wind early next week, will bring an elevated concern for fire risk that will be continued to be monitored.
Speaking of next week: The trough and its cooler temps will depart, but exactly how quickly and in what manner depends on the strength of a developing ridge across the southeastern United States. Given that, an immediate return to widespread 90-degree temperatures by Monday is not anticipated, but temperatures are expected to reach those highs sometime later in the week. And even then, that heat would be short-lived if the trough lingers around with cooler air to come.
This story was originally published June 24, 2026 at 5:00 AM with the headline "Wednesday forecast for San Joaquin Valley: Hot with a cooldown soon to come."
