December 2014 North American storm complex
The December 2014 North American storm complex was a powerful winter storm (referred to by some as California's "Storm of the Decade") that impacted the West Coast of the United States, beginning on the night of December 10, 2014, resulting in snow, wind, and flood watches. Fueled by the Pineapple Express, an atmospheric river originating in the tropical waters of the Pacific Ocean adjacent to the Hawaiian Islands, the storm was the strongest to affect California since January 2010. The system was also the single most intense storm to impact the West Coast, in terms of minimum low pressure, since a powerful winter storm in January 2008. The National Weather Service classified the storm as a significant threat, and issued 15 warnings and advisories, including a Blizzard Warning for the Northern Sierra Nevada (the first issued in California since January 2008).
Satellite image of the system off the coast of California, on December 10, 2014, with the flow of the Pineapple Express marked by the yellow arrow | |
| Type | Extratropical cyclone Bomb cyclone Blizzard Nor'easter Winter storm Tornado outbreak European windstorm |
|---|---|
| Formed | November 30, 2014 |
| Dissipated | December 28, 2014 |
| Highest gust | 139 mph (224 km/h) (White Mountain Peak) |
| Lowest pressure | 960 mbar (28 inHg) |
| Tornadoes confirmed | 6 confirmed |
| Max. rating1 | EF0 tornado |
| Duration of tornado outbreak2 | 2 days, 12 hours and 3 minutes |
| Maximum snowfall or ice accretion | 14.6 in (37 cm) of rainfall (Petrified Forest) |
| Fatalities | 2 confirmed |
| Areas affected | Southeast Alaska, Western Canada, Contiguous United States, Great Lakes region, Eastern Canada, Southern Greenland, Iceland, United Kingdom, Ireland, Europe, Western Russia |
Part of the 2014–15 North American winter 1Most severe tornado damage; see Enhanced Fujita scale 2Time from first tornado to last tornado | |