A storm out of the Gulf of Alaska will drop about a tenth of an inch of rain along the San Diego County coastline early Friday, 0.30 inches across inland valleys and foothills and 0.50 inches to 0.70 inches in the mountains, the National Weather Service said. The county’s highest peaks also could receive about a half-inch of snow from the storm, which will bring unusually cold air to the entire region. The temperature at and near the coast will drop to about 50 degrees before dawn Saturday and into the mid-40s before dawn Sunday. Inland valleys and foothills will drop into the low 40s and upper 50s on both of those days. Ramona could slip to 31 degrees early Sunday. It also will be quite chilly during the day. Forecasters say the temperature will only rise to 61 in San Diego on Friday and Saturday, which is 10 degrees below average. The storm will clear off to the east by noon by Saturday. But forecasters are expressing concern about the moderate to strong Santa Ana winds that are expected to arrive late Monday and last into Thursday. Concern is high because the region has received very little rain of late. San Diego has recorded only 0.10 inches of precipitation since Oct. 1, when the new rainy season began. That’s 0.66 inches below average. Friday’s storm “isn’t going to be a fire-season ender,” said Alex Tardy, a weather service forecaster.