Dry weather with areas of smoke and near-normal temperatures are forecast through the weekend. Gradual warming trend will begin next week.


Upper low that brought gusty winds to ongoing fires has shifted northeast over Idaho. Trough extends south through Nevada with winds beginning to turn north downvalley tonight with downslope winds draining out of the mountains.

Big question is how much smoke will drain west and south from fires, at 4 am all sites from Redding to Stockton have good visibilities with no smoke reported. This already shows that smoke forecast from HRRR is off, as it would have under low vis at Redding and Red Bluff at present.

It appears most of the smoke is elevated shown in periodic ceiling reports of 4000 feet at Redding and Red Bluff. Most of the smoke forecasted to come down the west part of the Sacramento Valley seems to be coming from the McFarland fire and a good bit of this seems elevated, which throws a lot of uncertainty in just how much smoke will affect the area today.

Would anticipate smoke from the Dixie and River fires to be more surface based, causing more impacts over foothill locations with west and northwest drainage likely through mid morning. Northwest winds over the Sacramento Valley may keep most of this smoke in the foothills say above 1000 feet, we will have to see how this plays out this morning. Will keep widespread smoke in the forecast given uncertainty.

North winds should not be long lasting, as at least weak onshore flow resumes this evening into Saturday and could provide some smoke improvement for Valley locations. However, smoke is likely to remain over the foothills and mountains, where downslope drainage occurs the next few nights and onshore gradient will not be strong enough to clear things out. High temperature forecast will be highly variable given smoke, but any brief clearing could allow temperatures to warm quickly during the late afternoon with 850mb temps rising quite a bit today. Valley areas outside of smoke could see readings near 100 degrees.

Weak onshore flow pattern should continue into early next week, as trough passes through the Pacific Northwest, keeping temperatures near normal warming to slight above normal by mid-week.

Extended Discussion (Tuesday through Friday)

Dry with a warming trend over interior NorCal through the extended forecast period as heights slowly increase. Triple digit heat in the northern and central Sacramento Valley Tuesday, expands throughout most of the Central Valley by the end of next week.