June 10, 2020 – Dry weather with moderate heat risk thru Thursday. Cooler temps, breezy winds and shower/thunderstorm chances return Friday into the weekend.

Discussion

Clear skies cover the region early this morning as the mid/upper ridge axis moves overhead NorCal. Winds are generally light other than a hint of a Delta Breeze at Travis AFB with 13 kts out of the southwest. Current temperatures are considerably milder across most of the area compared to 24 hours ago and range from the mid 30s to lower 40s in the colder mountain valleys, to the mid 60s to lower 70s across the Central Valley and foothill thermal belts.

Temperatures will continue to climb across interior NorCal today, and much of the region will be around 3-8 degrees warmer compared to Tuesday’s highs. While still hot on Thursday, most areas will see a few degrees of cooling compared to today as the ridge shifts further east ahead of the approaching late-week trough. The result will be moderate heat risk today and Thursday which may impact sensitive groups including outdoor workers.

Onshore flow increases Thursday evening ahead of the aforementioned trough with breezy winds and significantly cooler temperatures expected on Friday and Saturday. Although humidity values will be increasing with this system, breezy winds may create some fire weather concerns by increasing the risk of any fires spreads, especially for grasses and other fine fuels. Chances for showers and storms begin on Friday morning for the northern mountains, spreading southeast later Friday into Saturday.

Extended Discussion (Sunday through Wednesday)

Drier and warmer weather returns for Sunday into early next week. Near to a little below average high temperatures are expected on Sunday, with Valley and Delta highs in the mid to upper 80s. Monday higher temperatures will rise to around 2 to 7 degrees above normal, with Valley highs in the low to mid 90s. Heat Risk will generally be low, locally moderate in the Sacramento area. Temperatures drop a couple of degrees Tuesday and Wednesday as a trough pushes through, with precipitation limited to the Pacific Northwest.