Tuesday evening forecast May 11
A May gray pattern is here to stay, as the marine layer will persists from night to morning but expected to become less extensive each day through Thursday. Due to a ridge of high pressure aloft this will allow onshore flow to decrease and then prompt warmer temperatures across the interior valleys, with inland highs staying above average until Thursday. A cool down arrives through the weekend, as a trough sweeps across the area allowing onshore flow to strengthen.
Coastal clouds and areas of fog will clear faster each day, prompting more sunshine and inland warming. Daytime highs along the coast will reach the 60s to 70s, while valleys warm in the 80s to 90s. A warm air mass will start to weaken and shift east by Thursday as the next trough arrives over the Pacific Northwest.
The trough will develop into a cut off low by the time it arrives in California on Saturday. This are of low pressure will stay parked over the weekend, prompting cooler temperatures and more cloud cover. With stronger onshore flow this will also create a deeper marine layer, with the chance of drizzle or light rain especially across foothills. Otherwise conditions are likely to remain overcast, with little to no clearing at all. Temperatures this weekend will warm 50s to 60s along the coast and 60s to 70s inland.
The trough will shift east late Sunday with a slight warming trend on Monday and Tuesday. The marine layer is likely to clear quicker as the low should have shifted more easterly. Along with warmer air moving along the western portion of our state.
