Spring is here, and below-normal precipitation will continue

Yesterday’s weak cut off low brought some light rainfall to parts of southern and central California, but almost every place that was lucky enough to see the wet stuff received less than 0.25 inch (and most places didn’t tip the bucket at all). In fact, it was a warm and sunny day in Northern California. None of this precip was hydrologically significant, and in most places it wasn’t even enough to keep down the dust. Very warm and dry conditions will develop for the next 4 days or so (temps above 70 almost everywhere) before a Gulf of Alaska trough begins to cool things off by early next week. Yesterday’s GFS had a pretty impressive cold trough moving into CA next week with low snow levels and a high probability of convective activity; now, the models have a much less dramatic system moving in by Wednesday of next week, one that may not be able to generate any showers at all. We’ll see what happens; really, though, it does not look too promising. After a fairly wet early winter season, precip defecits have begun to increase significantly over most of CA (consistent with a La Nina winter) , and much of NorCal has already fallen below 80% of normal once again. The last Sierra snow survey had good news, but I’m not sure about the results of the April 1st and April 15th surveys. If we do not get any more significant precip this season, we’ll once again be looking at possible water problems next year (though more immediate concerns have been staved off by the early season surplus).

Spring is here, and below-normal precipitation will continue Read More »