Storm brings chance for rain starting Thursday

Warm and dry conditions will persist through Wednesday. On Thursday and Friday, a low pressure system will bring some rain, snow and even a slight chance of thunderstorms to the area. A chance of showers will persist Saturday and Saturday night. Dry and warmer conditions are expected early next week.

Ridge will be on its last legs Tuesday night/Wednesday then a low will move towards/across the area on Thursday/Friday. Weak diurnal flow will prevail tonight/Wednesday with moderate west to northwest flow on Thursday and Friday. With the above pattern, a bit of weather whiplash will be on tap for the area.

For Wednesday, the lingering upper level ridge and weak offshore gradients will allow for one more warm day. There will be some cooling with temperatures dropping into the 70s, from the mid 80s.

During the day, high clouds will begin to increase as the upper low approaches the area. As for winds, any offshore winds in the morning will be localized with speeds below advisory levels. For Thursday/Friday, the pattern changes noticeably. An upper low will develop off the Central Coast on Thursday then will move inland over the area Thursday night and Friday. This low will have some moisture to work with, bringing some measurable rain to the area. Rain will start across the Central Coast Thursday afternoon then will spread south and east Thursday night and Friday. Current rainfall estimates are expected to generally range between 0.25 and 0.75 inches. Also with a rather impressive cold pool moving overhead Thursday night/Friday, will be adding a slight chance of thunderstorms for all areas. Brief heavy downpours and small hail will be the likely threats. Snow levels on Thursday will generally be above 6000 feet, but will drop to the 4500-5000 foot range Thursday night and Friday. So, some accumulating snowfall will be likely at the higher elevations. Along with the precipitation, much cooler conditions will develop with temperatures in the mid 50s to lower 60s by Friday. As for winds, expect some gusty southwesterly winds as the onshore gradients increase and could flirt with advisory levels across the mountains and interior sections. 

For Saturday/Sunday, cyclonic flow over the area with a couple of impulses forecast to sweep across the area. Models differ in timing of the impulses and the rain chances. However, looks to be enough there to include a threat of precipitation Saturday and Saturday night. Any rain with this scenario looks to be less than the Thursday/Friday situation, with the area expected to get additional amounts of 0.25 inches or less. With the cyclonic flow and unsettled conditions, temperatures will remain on the cool side in the mid 50s to lower 60s. Gusty west to northwest winds will likely continue.