June 9, 2020 – Dry weather with a warming trend through mid-week. Cooler temps and possible precipitation chances return by the weekend.
Discussion
Other than a few high clouds drifting across the far northern portion of the state, skies are clear across the region early this morning. Winds are lighter compared to 24 hours ago, and current temperatures are a mixed bag with some areas cooler while others are significantly milder. Current readings range from the mid 30s in the colder mountain valleys, to the upper 50s to mid 60s across the Central Valley and Sierra foothill thermal belts.
Mid/upper ridging builds over NorCal today into Wednesday before shifting east on Thursday as another trough approaches from the Gulf of Alaska. Areas of moderate heat risk will be possible in the valley and foothills as the heat peaks on Wednesday and Thursday with highs returning to the mid 90s. This may pose a risk to groups sensitive to heat including outdoor workers. Low temperatures do drop into the lower to mid 60s which will provide some relief to the heat.
Cooler temperatures return Friday as onshore flow increases and synoptic cooling from the trough begins to impact the area. Best chance of showers will be across the northern third of the forecast area on Friday.
Extended Discussion (Saturday through Tuesday)
Guidance remains favorable for the long wave trough this weekend, leading to cooler weather and the chance for mountain and foothill showers on Saturday. Precip in the northern Sacramento Valley is possible as well; however, the best chances are currently tied to the terrain. Behind this trough, weak ridging builds over the West bringing warmer and drier weather back to interior NorCal. Valley temps are forecast to be in the upper 70s and 80s this weekend, with the low 90s returning for early next week.