Here’s what to expect for US winter weather after a cool October, Ars Technica

The Kincade Fire burns north of California's Bay Area on October 29. — Enlarge/The Kincade Fire burns north of California’s Bay Area on October 29.

Each month, the US National Oceanic and Atmospheric Administration (NOAA) puts outan analysisof the previous month’s weather after the final tally. The most recent update covers an odd Octoberfor the US, where the month included some terrifying wildfire conditions in California. This latest analysis also provides the long-range outlook for the winter months.

October provides another good reminder to Americans that their country is not the entire planet. Courtesy of the jet stream doing its thing, the western US experienced notably cool temperatures for much of the month. A dozen states had Octobers that ranked somewhere around the 8^thcoldest on record. Despite warmer temperatures along the East Coast, it was ranked as the 21^stColdest for the nation.

Lookingglobally, however, the western US was an outlier. Overall, it was the 2^ndwarmest October on record, behind only 2015. And with most of 2019 behind us, the final number for the year is crystallizing. NOAA puts the odds of 2019 being among the five warmest years on record at more than 99 .9%. (So they’re saying there’s a chance.) More specifically, there’s now about an 85% probability of coming in second behind 2016 – exactly the prediction weshared in early February.

Of course, October also saw a number of fires in California, and the state was in near-constant warnings of dangerous fire conditions, which were accompanied by massive (imposed) power outages and evacuations. We saw a repeat of the ugly combination of weather that led to deadly fires in recent years — a late arrival of the rainy season and strong Santa Ana and Diablo wind events.

Many areas hit record measures for vegetation dryness, including the nearly 78, 000 acres that burned in theKincade Firenorth of the Bay Area. And as high air pressure formed over the interior of the West, the ingredients were there for fast, dry, warm winds racing downslope over California mountains and toward the sea, stoking wildfires like bellows.

California wasn’t the only place feeling dry, as drought conditions extended across the Southwest, and only enough rain fell to barely help with drought in southern Texas. But again, the eastern half of the country was very different, with a great deal of precipitation lifting last month to the 8^thwettest October on record for the nation as a whole.