November in the West
November was drier than normal across much of the West, most notably in the intermountain region. Areas of above normal precipitation were observed along the Pacific Northwest coast, across Arizona and New Mexico, and in the Wyoming Rockies. Temperatures were above normal West-wide, with the greatest departures, in excess of 6 F (3.3 C) above normal, observed across the northern tier of the region.
Several storm systems impacted the West in November, though they were generally moisture-limited and did not produce significant precipitation totals beyond the coastal mountains. In the Pacific Northwest, Quillayute, Washington, recorded 25.72 in (653 mm) of rainfall, 166% of normal. This was the 4th wettest November since records began in 1966. Further south, Eureka, California, logged 7.2 in (183 mm) in November, 107% of normal and the 7th wettest since records began in 1945. In southern California, scattered coastal areas observed near normal precipitation, beneficial for the drought-stricken area. Pismo Beach recorded 1.91 in (49 mm), 126% of normal. Arizona and New Mexico observed above normal precipitation, most of it associated with two storms. The first, a cutoff low-pressure system, produced widespread thunderstorms during the 3rd-5th. The second storm, a deep trough moving in from the Pacific, impacted the area on the 21st-22nd. In northeastern Arizona, Show Low reported a monthly precipitation total of 2.55 in (65 mm), 193% of normal. This was the 3rd wettest November in a 33-year record. Albuquerque, New Mexico, recorded 1.03 in (26 mm), 180% of normal and the 12th wettest November since records began in 1891. In western Wyoming, Lander reported 1.49 in (38 mm) precipitation for the month, 173% of normal. This was the 11th wettest November in Lander since records began in 1946. Drought conditions in the western Great Basin were scaled back this month in the US Drought Monitor. This was attributed mostly to October rains that reduced the long-term precipitation deficit and improved soil moisture and stream flow rather than November precipitation. Drought improvement was also noted in northern New Mexico and along the western Wyoming-Montana border.
A broad upper level ridge dominated over the northern tier of the region this month, supporting drier than normal conditions over the Great Basin, Inland Northwest, and Montana. Along the Oregon-Nevada border, Denio reported only 0.03 in (0.8 mm), 3% of normal and the 3rd driest November since records began in 1951. Helena, Montana, observed only 0.02 in (0.5 mm) precipitation, 4% of normal and 2nd driest in a 79-year record. Small areas of Colorado and Montana saw expansion of drought conditions this month, mostly just denoting abnormally dry conditions.
The ridge producing dry conditions over the northern interior West also favored above normal temperatures. In eastern Washington, Spokane observed an average November temperature of 43.5 F (6.4 C). This was 7.8 F (4.3 C) above normal and the 4th warmest since records began in 1881. Further east, Lewistown, Montana, reported a November average temperature of 41.8 F (5.4 C), 9.8 F (5.4 C) above normal and the 5th warmest in a record that began in 1896. Coastal southern California experienced a heat wave and Santa Ana winds roughly November 9-14th. Chula Vista reported its hottest November day in a 99-year record, reaching 98 F (36.7 C) on the 9th. San Diego logged its second warmest November on record at 65.8 F (18.8 C), 4.5 F (2.5 C) above normal. Records for San Diego began in 1939. There were no locations in the contiguous West reporting below normal average temperatures this month.
In Alaska, the first two-thirds of the month were much warmer than normal across the majority of the state. The last third of the month saw the first consecutive days of below normal temperatures statewide in 2016; many interior locations saw temperatures below -30 F (-34.4 C). Average November temperatures in areas north of the Brooks Range were 5-10 F (3-6 C) above normal. From Fairbanks to Anchorage and down through southeast Alaska, temperatures were 2-4 F (1-2 C) above normal. The west-central region from Nome to Bethel was slightly cooler than normal. Precipitation was below normal in a large swath from Bethel to Anchorage north to the Brooks Range – including the entirety of the interior. Along the North Slope, Kuparuk reported 0.8 in (20 mm) precipitation, 533% of normal and its wettest November since records began in 1983. Precipitation in southeastern and southwestern Alaska was near normal. Further south, drier than normal conditions were observed throughout Hawaii, resulting in expansion of drought conditions on the leeward sides of all major islands. Lihue, Kauai, reported its driest November on record at 0.4 in (10 mm), 9% of normal. Records for Lihue began in 1950. Temperatures were variable across Hawaii, with some locations reporting above and some below normal. Molokai Airport recorded an average November temperature of 77.4 F (25.2 C), 2.6 F (1.4 C) above normal and the warmest since records began in 1949.
Significant Events for November 2016
November (all month): Slow start to snowpack in some parts of West: November storms added to the emerging snowpack across western mountains, though totals were generally not substantial. The central Great Basin, northern Sierra Nevada, Cascades, and southern Utah are off to a good start with snow water equivalent (SWE) generally >75% of normal. Across the Rockies and southern Sierra Nevada, SWE is generally below 75% of normal, with much of the northern Rockies seeing <50% of normal. However, it is early in the season and small amounts of snow can make the difference between being well above and well below normal at this point.