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KPBS Drought Tracker Update: Halfway Through Wet Season, Where Does CA Stand?

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KPBS Drought Tracker Update: Halfway Through Wet Season, Where Does CA Stand?
KPBS Drought Tracker Update: Halfway Through Wet Season, Where Does CA Stand? GUESTS: David Wagner, science & technology reporter, KPBS Dan Cayan,climate researcher, Scripps Institution of Oceanography

So far this winter in San Diego has felt like winter. We have had a fair share of clouds, chilly weather and amazingly rain. In Northern California it's been even weather the storm after storm passing through. But after six years of drought, we will take -- it will take an awful lot of wet weather to put California back on track. To assess rainfall and snow toddles we have an update from the KPBS drought tracker. Joining me is David Wagner, science and tech reporter. Welcome. [ INDISCERNIBLE ] is climate researcher with scripts institution of oceanography. Let's start with the big picture. Our new water year started on October 1. What to the snow and rainfall totals show so far? The big picture for the entire state is that we are doing pretty well when it comes to rain. Not as much when it comes to snow. So when you average out rainfall across the entire state, what you see is that California has so far received about 58% of what normally falls between October 1 and April 1. That is the six-month wet period. Today you can think about it this way. We are halfway through that season, but in terms of rain, we already more than halfway towards normal rainfall. So doing pretty well there. Looking at snow, we have not seen as much growth so far. The average snowpack measurement is only at 24% of a normal April 1 measurement. So the wet season is not over yet. There's still time for snow to fall. But the snowpack definitely has catching up to do. David, how does that compare to previous years? When we look at today's numbers and compared them to previous years in the drought, what we see is that the rain numbers are the biggest that we have seen since 2012. So rain is doing much better than in many previous years in the drought. One interesting thing is actually the rain numbers from this year are blowing past the rain numbers from last year. You will remember there was this El Niño in effect that was expected to bring a lot of rain to California. So even though we have this year a week La Nina no in effect which is the flipside which is more associated with drier conditions, we're still actually getting more rain this year than last year. Looking at snow numbers, they are pretty comparable to previous years in the drought. This is not the lowest December snowpack, but it is not the biggest either. Since it has been better -- weather, why have we not seen much of an increase in the snowpack? I think it is the timing and the character of the storms. These storms we've had this year has been wet and a lot of that the precipitation is actually fallen as a liquid rather than snow. Meeting the storms have been relatively warm. So we will see what the remainder of the winter does as far as stormy this and storm characteristics. David, remind us why the Sierra Snowpack is still so crucial to California. We look at the Sierra Snowpack because it is a really important source of water for so much of the state. Here in San Diego we actually rely a bit more on the Colorado River system for our water, but if you want a big picture of water supply in California, for many Californians, Sierra snow is this crucial natural reservoir where the snowpack builds up over the winter and as it melts it provides this really needed natural source of water for so much of the state. How much of San Diego's water supply still comes from northern California? I don't have that number off the top of my head, but more than half of our water comes from the Colorado River system. We are a little bit different than a lot of the state. A lot of other parts of Southern California even even that a lot -- in that a lot of our local water comes from outside the state. We look at the Sierra Snowpack to give that big picture look at water supply in California and just how the state overall is faring. Dan, even if the storms are too warm for snow, doesn't the rain increase the water supply in the same way? It does. An hour reservoir storage has been relatively on the low side, so a lot of the water that is running off is getting captured in are built reservoir system. The other thing to remember is, because we have had such a drive period -- DRY period leading up to this winter, much of the water that is falling is rainfall, at least initially is soaking in to the landscape and is really not that usable in the form of human consumption, but as time wears on, the system is going to get more saturated and hopefully we will generate an ample runoff. So the fact that this water is being absorbed by the ground is good long-term, but what you are saying is it is not the kind of resource for water supply that he snowpack would be. Yes. The snowpack has some desirable attributes in that it waits until later spring and summer off into melts and runoff, which is the period of intense consumption. It is also the period beyond when we would expect to really have heavy storms. So you can start filling reservoirs to their upper capacity. We talk about six years of drought in California David, but this is a very big stay. So not all areas of California are equally affected is that right? That's right. When you look at the US drought Monitor, what you see right now is that some parts of northern California are now officially drought three. Here in San Diego we are still mostly in was called a state of extreme drought according to the US drought Monitor, and that is true of much of Southern California. But we have definitely seen drought conditions ease in certain parts of the state. I think the statistic I have here is that today 70% of the state is still in severe drought or worse. One of those categories. That is definitely an improvement over last year when 97% of the state within that category. So for parts of the state, it is getting better, but definitely here in San Diego and for so much of the state deathly don't see the drought is over yet. Where can people go to get more information about the drought tracker? They can go to KPBS.org flash drought tracker and track numbers to previous years to really get a sense of how things have been changing and where we stand now. I've been speaking with science the tech reporter David Wagner and Dan, climate researcher with Scripps institution of oceanography. Thank you both.

KPBS Drought Tracker Update: Halfway Through Wet Season, Where Does CA Stand?
After a week that brought rain and snow to San Diego County, an update from the KPBS Drought Tracker shows statewide rain totals growing at a steady pace, but the Sierra snowpack struggling to keep up.

After a week that brought rain and snow to San Diego County, an update from the KPBS Drought Tracker shows statewide rain totals growing at a steady pace, but the Sierra snowpack struggling to keep up.

We're now close to halfway through California's wet season, defined as the six months between Oct. 1 and April 1. So far, statewide rainfall is running a bit ahead of schedule. As of Monday morning, the state has received 58 percent of what normally falls by the beginning of April.

This year's rainfall eclipses totals recorded on this day in 2015, when a strong El Niño was expected to deliver above-average precipitation. A weak La Niña — a weather pattern typically associated with drier conditions in California — hasn't prevented storms from drenching parts of the state this year.

But warm temperatures have prevented the Sierra snowpack from keeping pace with rainfall. On average, snowpack measurements are hitting only 24 percent of the normal April 1 measurement.

Scripps Institution of Oceanography climate researcher Dan Cayan helped compile this data. He said despite the lackluster start, there's still time for the snowpack to grow.

"The winter's not over yet," Cayan said. "It doesn't mean that we won't get some storms that are relatively cool and large snow-generators. So, we'll see."

The Sierra snowpack serves as an important source of water for many parts of California leading into warmer summer months. Rain is helping to fill California's reservoirs. But Cayan notes that after six years of drought, parched soil is absorbing lots of rainfall, and not as much water is being captured as possible.

"Since it's been pretty dry in the last several years, some of that water really hasn't run off," said Cayan. "We're still in a catch-up mode as far as recovering from the long period of dryness we've had."