National Weather Service breaks down why South Valley gets less rain than other parts of Valley

Monday, February 20, 2017
HANFORD, Calif. (KFSN) -- It was a busy day for the meteorologists at the National Weather Service in Hanford. They tracked storms throughout the Central Valley, and while we were there, sent out a flood advisory for the foothills and mountains.

When talking about the abundance of rain this season, Meteorologist Jim Andersen says there can be too much of a good thing, evident in flooding events or rockslides.

But after several dry years without storms, he says the numbers are refreshing to see.

Since October 1st, Fresno, Madera, and Merced have all seen more than 12 inches of rain.

And while Bakersfield and Hanford are also above normal levels, the South Valley just doesn't get as much rain, for a couple of reasons, including what's called rain shadowing.

"We're kind of getting the remnants from whatever makes it over the coastal range," Andersen said. "And so we see less rain than the coastal range would typically, just because of that barrier."

Additionally, and most importantly, Andersen says it's the typical location of the storm track, which he says sets up north of Merced County, that explains higher rain totals in the North Valley. However, he says the storm track can shift, as we saw in Southern California this weekend.

"As you go through normals and look from the 30 year normal, you're going to get that precipitation amount trending less as you go south," Andersen said.

The South Valley may not match the rain totals in the North Valley, or come close to what's happening in the Sierra.

But it's still wet, and the winter season is far from over.
Copyright © 2024 KFSN-TV. All Rights Reserved.