The Bee on Thursday hosted a live chat at www.sacbee.com/live with National Weather Service forecaster Brooke Bingaman about the series of warm, wet storms moving through California this week.

There has been anxiety about these storms because of the high rainfall predictions: as much as 15 inches by Sunday in the Mount Shasta region, 12 inches in parts of the American River watershed, and 5 inches in the Sacramento metro area.

The first storm on Wednesday was the weakest of three, and it caused some people to wonder if the forecast missed the mark. But Bingaman said residents should not be deceived and should continue to plan for heavy rain, strong winds and localized flooding.

Weather officials late Thursday upgraded their flood advisory to a "warning" for most of Northern California as the second in a series of warm, wet storms moved into the state.

The flood warning, issued by the National Weather Service, lasts through 3:15 p.m. today and covers virtually all of the state's interior from Woodland north. A warning means that flooding is imminent or has already been reported.

Here are edited highlights from the discussion.

What is your prediction for the storm? Is this all just overblown?

Definitely not overblown. The amount of moisture coming into NorCal is similar to the flooding back in January of '97. So, yes, significant.

How do the rain expectations compare to 15 years ago when Roseville flooded so badly?

The good news is that our reservoirs have a lot of capacity that will mitigate some of the main stem river flooding. But unregulated rivers and streams will easily flood. For the Sacramento-Roseville area, we are looking at rain totals of 5 to 6 inches, so this will cause a lot of small stream and urban flooding.

What are the best things to do to prepare for a storm like this? Stay off the roads?

Motorists definitely need to be extra cautious this weekend. A U.S. study on flood fatalities in 2011 showed that most flood deaths (63 percent) are due to people driving near or through flooded areas. Do not cross flooded roads, as it only takes 1 to 2 feet of moving water to wash away a car or SUV. The other thing people should prepare for is power outages that may extend for a day or several days.

Are these "pineapple express" storms? And what exactly is a pineapple express storm?

Pineapple express storms refer to moisture plumes that originate near Hawaii (in the tropics) and head toward our area. This storm is not totally tropical so it's not a true pineapple express storm. However, it is somewhat similar since we are not looking at a traditionally cold storm. We will have high snow levels with this event.

Will these systems produce enough to fill the Yolo Bypass?

Bypasses throughout NorCal are expected to get water. The upper Sacramento River will get a lot of water this weekend and weirs will overflow into the bypasses.

How confident are you in the predictions for this bad rain and storm?

The computer forecast models have been very consistent leading up to this storm, so our confidence is high on the magnitude and timing of this event.

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