SLO County weather forecast for the week of March 9: Heavy rain is on the way

Since late January, the Eastern Pacific High has been firmly anchored off the West Coast and produced a dry spell. In fact, one of the longest mid-winter droughts since rainfall records have been kept.

Late last week, the Eastern Pacific High moved westward toward the International Date Line, opening the door to a series of low-pressure systems which will produce increasing clouds, southerly winds and rain.

An upper-level trough will produce mostly cloudy skies and scattered rain showers through Sunday morning.

At this time, most areas should receive between 0.10 and 0.25 of an inch of rain. A break in the rain is forecast Sunday afternoon through Monday morning.

However, the break from dry weather will be brief as a cutoff low-pressure system is expected to move southward along the Central Coast and produce increasing southerly winds and periods of rain later Monday through Wednesday.

Precipitation accumulation through Wednesday will range from 0.75 to 2.25 inches, with the elevated terrain along the coastline getting higher amounts.

Temperatures are expected to warm behind this system, with thermometers climbing to above average and snow levels above 6,000 feet.

Mostly dry weather with a chance of a few scattered rain showers are expected on Thursday and Friday, with temperatures remaining seasonably warm.

The long-range models suggest another weather system may move through the Central Coast next weekend, with the possibility of additional precipitation.

Details on strength and timing remain extremely unclear; updates will be given as the forecast evolves.

Overall, it appears that California is in a weak wet weather pattern for the next seven to 10 days with brief breaks in the wet weather expected.

Surf report

A 5- to 7-foot northwesterly (310-degree, deep-water) swell (with an 8- to 12-second period) is forecast along our coastline on Monday into Wednesday. Combined with this northwesterly swell will be 4- to 6- foot Southerly (195-degree, shallow-water) seas (with a 4- to 7-second period) on Monday through Wednesday.

Seawater temperatures will range from 56 and 58 degrees Fahrenheit through Friday.

This week’s temperatures

LOWS AND HIGHS, PASO ROBLES

LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS

PG&E safety tip

Rain after a dry period releases oil, grease and rubber dust that has accumulated on roadways, creating slippery conditions.

Driving too fast is the No. 1 cause of traffic accidents on wet days. Tragically over the years, first responders, such as CHP officers, firefighters, Caltrans highway workers, and Pacific Gas and Electric Co. line crews have been hit by vehicles.

One of the most significant hazards for workers along highways is motorists who do not exercise caution while driving through work zones.

So please, “Slow for the Cone Zone.”