Incoming storm to bring heavy rain across Southern California: See an updated timeline

Weather Forecast: Tuesday, Nov. 11

The latest forecast and air quality conditions for the greater Los Angeles area, including beaches, valleys and desert regions.

LOS ANGELES - Southern California is bracing for a significant weather pattern change this week, transitioning from warm, above-average conditions to much cooler temperatures and a chance of rain by Thursday, according to the National Weather Service.

When will the storm peak?

Timeline:

The peak of the storm is expected Thursday into Friday, with storm totals through that time ranging from 1 to 2 inches, with 2-4 inches in the mountains and hills. 

Weather Forecast for Tuesday, Nov. 11

The latest forecast and air quality conditions for the greater Los Angeles area, including beaches, valleys and desert regions.

Tuesday

 Cooler conditions begin, though highs remain slightly above average. Coastal areas will reach up to 80 degrees.

Mid-week

The marine layer deepens, reducing the chance of coastal fog and spreading cooler conditions inland. High temperatures west of the mountains will return to near-normal levels by Wednesday.

Thursday through next weekend

Temperatures across the region will drop substantially, and a chance for rain will develop. This is also when the best chance for snow will unfold, with snowfall totals likely to be from one to two feet at elevations of 7,000 or 8,000 feet and above. 

According to the National Weather Service, weak Santa Ana winds are contributing to the warmth in Southern California but are not expected to significantly heighten wildfire risk due to higher humidities.

Forecasters suggest there could be off-and-on rain chances into Saturday afternoon.

Where will it rain the most?

What we know:

Here's a breakdown by county on rain chances and timing: 

Los Angeles County

• Wednesday night: 0-10% chance
• Thursday morning: 10-30% chance
• Thursday afternoon: 10-30% chance
• Thursday evening: 50-70% chance
• Friday: 50-70% chance, 10-20% chance
• Saturday: 50-70% chance
• Sunday: 30-50% chance

Santa Barbara County

• Wednesday night: 10-30% chance
• Thursday morning: 30-50% chance
• Thursday afternoon: 70-100% chance, 10-20% chance of thunderstorms
• Thursday evening: 70-100% chance, 10-20% chance of thunderstorms
• Friday: 50-70% chance, 10-20% chance of thunderstorms
• Saturday: 30-50% chance
• Sunday: 10-30% chance

San Luis Obispo County:

• Wednesday night: 10-30% chance
• Thursday morning: 30-50% chance
• Thursday afternoon: 70-100% chance, 10-20% chance of thunderstorms
• Thursday evening: 70-100% chance, 10-20% chance of thunderstorms
• Friday: 50-70% chance, 10-20% chance of thunderstorms
• Saturday: 10-30% chance
• Sunday: 10-30% chance

Ventura County

• Wednesday night: 0-10% chance
• Thursday morning: 30-50% chance
• Thursday afternoon: 30-50% chance
• Thursday evening: 70-100% chance, 10-20% chance of thunderstorms
• Friday: 50-70% chance, 10-20% chance of thunderstorms
• Saturday: 50-70% chance
• Sunday: 10-30% chance

Orange, Riverside, and San Bernardino counties

Graphic courtesy National Weather Service

Graphic courtesy National Weather Service

What we don't know:

The NWS said there is still some uncertainty regarding the storm. The latest models predicting future weather are presenting a range of possibilities for the total amount and exact timing of the rain, and the projects could change in the coming days, forecasters warned.