Dry and mild with above average temperatures today. Scattered showers and mountain snow Thursday into Saturday.
Discussion
Satellite imagery shows the wide plume of clouds and deeper moisture over the eastern Pacific moving up from the southwest ahead of the approaching trough. Current temperatures are mild ranging from the mid 40s to mid 50s across the Central Valley. Appears we’ll see more high cloudiness over the area today as the upper ridge moves gradually east.
Temperatures in most areas will be down a few degrees compared to Tuesday due to the cloud cover despite little change in overall airmass.
Models have been struggling with the digging trough over the Pacific and they have trended slower and further west with the first short wave the trough begins to split. The first wave digs south off the coast tonight and Thursday before moving into SoCal Thursday night. Shower chances will be mainly confined to areas closer to the coast, though western portions of the forecast area may see a little precipitation.
Another short wave trough will dig out of the Gulf of Alaska on Friday and push over CA. We should see better forcing and more impacts over our area with this trough. There is some variability with this trough also but overall seems less than the first trough but we still could see it shift west or slow down. The best chances for showers will come in the afternoon and evening which isn’t great timing for those planning to head up into the mountains for the weekend.
Snow levels will start out around 7000 ft early Friday but will lower to around 4500-5500 ft Friday evening. Snow levels will continue to lower Friday night into early Saturday getting as low as 2000 ft Saturday morning. Light accumulation possible down to 2000 feet.
The majority of the snow accumulation will be above 4000 feet with 5-11 inches, with higher amounts over some of the higher peaks. Travel impacts will be possible, and a Winter Weather Advisory may be needed.
For QPF its looking to be 0.50-1.50″ over the higher elevations with 0.10-0.50″ over the Valley. Sacramento tied its record yesterday for the number of consecutive dry days during the wet season with 52 days (old record 2013-2014). Rain either Thursday or Friday means the new record may stop at 54 or 55 days.
Extended Discussion (Sunday through Wednesday)
Upper low progged to dig through CA Sunday although models differ on westward extent of this feature and amount of available moisture. NBM leaning towards a drier solution with a few afternoon snow showers possible over higher terrain of the Sierra Nevada. EPAC upper ridge progged to build inland over interior NorCal early next week. This will result in dry weather with warming temperatures and some locally gusty north to east wind.