San Diego will be drenched with days of rain that could lead to dangerous flash flooding and gusty mountain winds as the heaviest downpours move in Thursday.
NBC 7 Meteorologist Dagmar Midcap said light showers will turn into heavy rains at around sunrise Thursday.
Breezy and windy conditions will pick up in the late afternoon as the heavy rain weakens to isolated showers throughout the county.
48-hour rainfall totals are as forecasted:
San Diego: 2.17"
El Cajon: 3.32"
Chula Vista: 2.63"
The storm system will also bring gusty winds to the region.
A high wind warning went into effect at noon Wednesday until 10 p.m. Thursday.
Coastal and inland areas will see winds average 25 to 35 miles per hour. In the mountains, winds will be much more severe. Gusts of up to 65 mph are possible, Parveen said.
"Don't think it's not going to rain. Take the umbrella before you leave," NBC 7 Meteorologist Sheena Parveen said.
NBC 7 Meteorologist Llarisa Abreu was in Alpine Wednesday afternoon, seeing temperatures as low as 37 degrees.
Light rain and winds blew through San Diego's eastern region, as Abreu noticed large semi-trucks driving below the speed limit along Interstate 8 for safety.
Abreu spoke with the owner of Laguna Lodge on Sunrise Highway in Mt. Laguna about the storms. He said the rain has been good for business, but fears strong winds that could pick up and cause damage.
Ahead of the brunt of the storm, the National Weather Service on Wednesday issued flash flood warnings for the area near the San Diego River at Fashion Valley and the area near the Santa Margarita River at San Juan Capistrano.
A flash flood watch for all areas was set to take effect at 4 a.m. to 10 p.m. Thursday.
The heavy downpours are due in part to a subtropical jet stream that pulls tropical moisture into the region. Combined with the storm system, it creates an atmospheric river, Parveen said.
Both the morning and evening commutes will be wet and visibility will be poor, Parveen said.
After 6 p.m. Thursday, heavy downpours will start to taper off with light showers lingering into Friday morning.
In total, the storm could bring 2 to 3 inches of rain to the coast and inland valleys; in the mountains 6 inches or more of rain is possible and in the deserts, less than a half-inch is expected.