January is behind us, so here’s another update on rainfall and this year’s El Niño. Yesterday’s storm proved to be underwhelming across much of metropolitan LA, though the mountains did get a good dose of rain and snow. Downtown LA recorded 0.43”, for a January total of 3.17” – just above the average of 3.12”. The bad news is that thanks to dry weather in November and December, LA is still about 3” of rain below normal for the water year.
In fact, we are actually behind where we were at this point in water year (WY) 2012-2013, which turned out to be the worst year of the drought. Not exactly inspiring. The good news, of course, is that being in an El Niño year gives us much better odds of having a wet February-May than we had over the last four years.
I added the median to the graph in green for this update. Because of a few monster years, the rainfall distribution skews high; the median of just under 13” may be considered more typical than the average of just under 15”.
The other good news is that the season has not been so cruel to the rest of the state. Most of California is having an average to above average year, including much of San Diego County and the San Joaquin Valley. Much of the Sierra Nevada and the northern third of the state are at or above average – and being 25% above average there make a much bigger difference.
This has helped replenish reservoirs, especially in northern California. Lake Shasta and Lake Oroville, the two biggest reservoirs in the state, will soon have more storage than they had at the end of spring last year. Folsom Lake and Bullards Bar have actually crept above the historical average.
We’re including San Luis Reservoir (a large off-line reservoir in the southern Central Valley) in NorCal, because that’s where the water comes from. It’s below where it was last year but that’s likely due to restrictions on when water can be pumped.
Reservoirs in the central Sierra haven’t done as well, partly because they were all very low, and probably partly because the terrain is higher and more of the precipitation has fallen as snow.
This year, the state’s snowpack is in much better shape than it was last year, so there will be a good bit of water headed to the reservoirs this spring.
In the meantime, if El Niño is going to make a dent in LA’s drought, it might want to start soon.
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