The San Francisco Bay Area finally got more rain in February, but our drought deepened.
The next chart shows monthly rainfall for my home town near San Francisco, California. The measured rainfall for the month is shown in red; the normal monthly rainfall (average across many years) is shown in blue. The good news is that with two storms last week, we received 2.76 inches of rain in February, much more than any month since January 2013, and nearly as much as the total rainfall in the 13 months from January 2013 through January 2014!
But the bad news is:
- The actual rainfall (red bar) is lower than the normal rainfall (blue bar) for February, so the 2.76 inches in February was still below normal
- With the blue bars (normal rainfall) declining after February, we expect less rain in the coming months, limiting chances for rainfall to catch up in the spring before we enter the six-month dry period of our Mediterranean summer. The window for rain is starting to close.
- Our cumulative rainfall from January 2013 is shown below — our cumulative rainfall is 26% of normal. Therefore, the soil and plants are much drier than normal as rainfall tapers toward summer, increasing stress on plants and wildlife, particularly as the rivers and streams in the valley dry up.
Looking at the purple line below, our low temperatures continued well above normal in February. Plants with early blossoms and buds weren’t punished by killing frosts, but the higher temperatures might increase their need for water.
Our valley depends on water delivered from the rest of the state, and we’ve been told that deliveries will be curtailed. We’ll have to see how well water conservation mitigates the impact of reduced water deliveries. The local water district that distributes water from outside the valley has established mandatory reductions of 20% of our water usage. Conservation measures must be implemented by municipalities and local water suppliers, and there may be some lead time before these reduce water use. The longer it takes for water conservation measures to be put in place and take effect, the more drastic the water conservation measures that will be required.
During the 1976-1977 drought, we couldn’t water our lawns. The current drought is worse, but our water supply is better now. We’ll see how it goes.