The reason? Well, it’s the same old story: an increasingly resilient ridge of high pressure keeps re-developing and re-strengthening just west of the West Coast, in a perfect position to deflect the Pacific storm track. I don’t have a great deal of good news (or, really, anything new) to report regarding the outlook for the next 10-14 days (at least): it looks very dry and warmer than average essentially statewide. California precipitation anomaly to date (Oct 1 through Feb 2) via .īone dry outlook for next 2 weeks continues strong ridging and warmer temps dominate But the state would now be in dramatically worse shape were it not for that early season precipitation–a truly fortuitous stroke of luck. I still think it’ll end up dry (perhaps very dry), and the drought will persist (and perhaps re-intensify) through the summer and fall to come. Still, it remains the case that October and December’s precipitation totals have prevented the 2021-2022 Water Year from being catastrophically dry. Meanwhile, statewide average precipitation to date is still somewhat close to average for the date despite a record dry January thanks to the very wet Oct and Dec, though parts of the state have already burned through this substantial head start and more areas will start to be below average for the season to date over the next 2 (dry) weeks. Remarkably, however, statewide snowpack has plummeted from a remarkable 160% of average in late December to 87% of average as of this writing. And while November was pretty dry, December was quite wet and cold–and brought prodigious mountain snowfall. The much discussed “Bombtober” (the extreme atmospheric river event and record single-day precipitation event in NorCal brought about by the rapid strengthening, or “bombogenesis,” of an offshore storm in October) singularly made October 2021 the wettest October on record across most of NorCal. In this context, it is exceptionally fortunate that California received as much precipitation as it did early in the season. While that’s still not nearly as dry as it would be during summer or autumn–closer to the peak of fire season–there have been a handful of notable wildfires over the past month and this pattern could perhaps continue for as long as we continue to see near-zero precipitation and occasionally windy conditions this winter. ![]() #CAwx #NVwx /ZOPSxINp6f- Daniel Swain February 2, 2022Īs a result of these exceptionally dry and also warmer than average conditions, mid-winter snowmelt has begun in the Sierra Nevada and vegetation even across parts of normally very damp NorCal has dried out to levels more typical for May or June. This dataset is much longer–going back to 1895, but only extending through 2010. Here's another perspective using the PRISM dataset: still the driest Jan on record across much of the Sierra Nevada, San Joaquin Valley, & western NV. Due to the clear and dry conditions, temperatures were (on average) warmer than usual for January, but with a wide diurnal spread: overnight minimum temperatures were actually slightly *colder* than usual, but daytime high temperatures were significantly above average (and, thus, won out on in the monthly average). As a result, January 2022 will go down in the record books as the driest January on record (since at least 1895) for most of the San Joaquin Valley, the Central and Southern Sierra, and pockets of the Sacramento Valley and western Nevada. Some spots saw a bit of rain and snow during the first couple days of the month, but others saw nothing at all the last 25 days of the month brought essentially zero precipitation to the entire region. Well, I don’t need to tell most folks twice: January 2022 was an exceptionally dry month across most of California and Nevada. ![]()
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