July 26, 2018 – Excessive heat continues through Friday for the northern Sacramento valley and surrounding foothills and portions of the northern San Joaquin valley. A bit cooler this weekend through the middle of next week but still warmer than normal.
Discussion (Today through Saturday)
A strong ridge of high pressure is going to remain over NorCal on Thursday and that will bring another day of dangerous heat. Highs are going to be similar to what we saw on Wednesday pushing between 103 to 112 for the valley. Highs should remain below record levels. We will see some mid level moisture ride along the apex of the ridge and that may kick off an isolated t-storm in the afternoon but the threat looks to stay just north of our CWA.
An isolated storm may pop up in the far southeast part of the CWA over the Sierra but with a lack of forcing the threat will remain minimal.
The ridge will slowly move south on Friday and that will bring more of an onshore flow to southern part of the Sacramento Valley and northern San Joaquin Valley. Temperatures will be a bit cooler in those areas but still will push above the century mark.
Highs will be as hot as 111 in northern Sacramento Valley and the heat products will remain in effect through mid Friday evening. The ridge will remain in place over the SW for the weekend and we will stay hot but temperatures look to be cool enough to not need any heat products. If the ridge happens to push back north and west we may need look into extended products into the weekend.
Extended discussion (Monday through Thursday)
A ridge of high pressure over the southwest U.S. will dominate the weather pattern through the extended period. Stable west to southwest flow will keep any significant afternoon convection or thunderstorms out of the forecast.
A series of weak troughs moving through the Pacific northwest will suppress the ridge a bit bringing slightly cooler temperatures through the extended period than during the short term. Even with the cooling, however, daytime highs will remain several degrees above normal.