This browser does not support the Video element.
Rain moving in around Bay Area
A storm system arrived in the Bay Area Tuesday afternoon and the rain is sticking around until Wednesday night.
SAN FRANCISCO - The Bay Area shifted back into winter mode this week as rain moved in Tuesday, bringing a slight chance of thunderstorms.
Rain returns
What we know:
By Tuesday evening, most areas were reporting light to moderate rain, with precipitation expected to intensify overnight.
Meteorologists said the weather system is forecast to last through Wednesday night. Rainfall totals are expected to range from a half-inch to 2 inches across the region.
This latest round of rain breaks a more than one-month dry spell.
Storm headed to Bay Area: Here's when it will rain
It's been an exceptionally sunny February, so far. That's expected to end Tuesday by noon, when there are expected scattered showers, according to the National Weather Service.
Sierra winter weather advisory
Big picture view:
A winter weather advisory is in effect for the west slope of the Northern Sierra Nevada until 4 p.m. Wednesday.
Snow totals at higher elevations are expected to range from 10 to 20 inches.
What about the water supply?
In the South Bay there are concerns that California's typically wettest months aren't seeing as much rain as usual.
"To see, you know, a real big dry stretch there in January was not great for our water supply," said Matt Keller, public information officer for the South Bays Valley Water System.
Keller reviewed what had happened. "We did have a really wet start to the year, so we were looking pretty good coming out of December into January, but once January hit, we really didn't see much," said Keller.
But thanks to all that early-season wetness, Valley Water's reservoirs are still well off. "We were above the historical average at the beginning of January and right now we're at 96% of historical averages," said Keller.
In the North Bay, the Marin Municipal Water District's dams are 98.5% full.
California's six mega reservoirs today are 80% full. On January 7, the first day of our long dry spell, they were 78% full. So, in more than a month, at the peak of the rainy season, they only picked up a paltry 2%.
But, hope springs eternal. "But, you know, seeing those reservoirs pretty full right now is good news. So, the impact of the snow pack on those reservoirs isn't as great as when we see that snow pack when our reservoirs were really low or significantly low during the droughts," said Keller.
We are halfway though the rainy season with the balance of February and all of March to make it or break it.
Economic impact
As for that snow pack, the economic damage to the ski industry is significant. The lack of snow from the dry spell means bad business.
The snow pack year started off the new year at 71% of its historical average. Today it's only 58% of the average for this time of year.
Worse, it's only 37% of where it should be on April 1, a long, long way to go as far as needed snowfall is concerned, as we learned from the state's chief snowcaster last week.
"We've seen, you know, we've had these years before. Every year is different. We have so much variability in California, you know, how the rain falls, and the snow falls each year. And so, we've been in this position before, and we've caught up in the past some years and not in others," said Andy Reising of the California Department of Water Resource's Snow and Water Forecasting Unit.
Brief break before next storm
What's next:
Forecasters said the Bay Area is expected to see a break in the wet weather Thursday and Friday.
Another storm is forecast for the holiday weekend, with a stronger system potentially bringing another round of rain Sunday into Monday.
The Source: This story was written based on information from meteorologist Mark Tamayo and KTVU reporter Tom Vacar.