January in the West
January 2012 was a month of extremes in the West. Alaska experienced bitter cold and heavy coastal snows, while record-breaking highs and extended warm periods dominated the Southwest and Inland Northwest. Heavy rain and snowfall throughout the second half of the month helped much of the Northwest recover some of their moisture deficit, while the Southwest remained nearly dry.
Strong and persistent ridging took hold over the West for most of January 2012,resulting in positive temperature departures from normal for most of the region. The greatest positive departures were observed in the Rocky Mountains and especially the plains of Montana, with slightly negative departures seen in coastal areas of the Northwest. During the first week of January, record highs occurred throughout the West. At inland non-mountainous areas, temperatures in the high 50s F (13-15 C) into the low 60s F (16-17 C) were enough to meet or break records; in the Southwest, 81 F (27 C) in Phoenix on New Year’s day met the previous record high. Phoenix experienced its 4th warmest January on record (1895+). On January 2nd the high of 85 F (29.4 C) at the University of California, Los Angeles shattered the previous daily record of 80 F (26.6 C) set in 1969. Another less extreme but still quite widespread warm outbreak occurred mid-month (13-15th) with record temperatures tied or set in California, Nevada, southern Idaho, Utah, and Wyoming. The last few days of the month saw Santa Ana conditions and record temperatures in the neighborhood of 80 F (26.6 C) for Southern California and the Central Valley, as well as record daily highs in Wyoming, Nevada, and eastern Montana. Bakersfield, CA experienced its 10th warmest January on record since 1893 and Great Falls and Billings, Montana recorded their 15th and 16th warmest Januarys, respectively.
In stark contrast to mild January temperatures in the lower 48, frigid conditions dominated Alaska. Record lows were broken or nearly missed throughout the state in the first and last weeks of the month. On January 29 and 30, Bettles, Alaska reached -60 F (-51.1 C) breaking previous records of -56 F (-48.8 C) and -58 F (-50 C), respectively. By January 13, Nome had broken or tied 5 low temperature records with temperatures in the -30 F (-34.4 C) range. The low temperatures have allowed for Bering Sea ice to advance rapidly southward during the last week of the month at a rate of 10 miles/day (16 km/day), much faster than the usually observed rate of 2-3 miles/day (3-5 km/day). The advancing ice is expected to heavily impact the crabbing industry. Many locations throughout the state also set daily snowfall and precipitation records in the first part of the month, described in detail below.
Mid-January, a procession of moisture-laden systems tracked through the Pacific Northwest, bringing rainfall totals to over 100% of a normal January in much of Washington, Oregon, Idaho, and portions of Montana. Another strong precipitation event associated with a deep subtropical moisture tap occurred in the Northwest on January 24 and 25 and produced additional precipitation records, though in this case slightly further south, targeting southern Washington, Oregon, far northern Nevada, and Southern Idaho.
While the Northwest was being inundated, moderate drought developed or maintained through the month in Central and Southern California, the Great Basin, Arizona, New Mexico, and Hawaii. Phoenix, Arizona tied its driest January on record receiving only trace precipitation; normal at that location is 0.91 in (23 mm). Elsewhere in the Southwest, San Diego, California airport recorded 0.4 in (3.9 cm), tying for the 21st driest year in a record that began in 1914. In the Great Basin, Reno, Nevada completed its 56th consecutive day with no measurable precipitation on January 15th. The previous record stretch (in winter; the summer record is 129) had been 54 days from December 2, 1960 through January 24, 1961. Reno received late month precipitation to finish with a total of 1.54 in (39 mm), 0.48 in (12 mm) above the 1971-2000 normal, the first month since June 2011 with above normal precipitation. Reno ended a 7-month stretch (mid-June to mid-January) with a total of only 0.33” (8.4 mm).
Significant Events for January 2012
January 5-8: Heavy Snows in Prince William Sound, Alaska: Excessive snowfall occurred in Prince William Sound, Alaska over the past 6 weeks, causing avalanche hazards and dangerous snow loading on structures. Valdez, Alaska received record daily snowfall of 19.2 in (48.8 cm), 19.3 in (49 cm), and 15.2 in (38.6 cm) on January 5th, 6th, and 8th respectively. Season-to-date snowfall at Valdez reached 290.1 in (736.9 cm) by January 8, breaking the previous seasonal snowfall record (to that date); normal season-to-date snowfall is 143.3 in (364 cm). Cordova, Alaska also received heavy, above-average snowfall and declared a state of emergency due to many building collapses and extreme avalanche hazard.
January 16-21: Major Winter Storm in Northwest: A series of Pacific storms with ample subtropical moisture began passing through western Washington and Oregon on Monday, January 16th and continued through Saturday, January 21, moving into northern California, Idaho and Western Montana. Heavy precipitation occurred throughout the region, with many precipitation records set. The Seattle-Tacoma metropolitan area received 2-10 inches (5-25 cm) of snow, leaving many without power and causing closure of the Seattle airport. The airport received record snowfall of 6.8 in (17.3 cm) breaking the previous daily record of 2.9 in (7.4 cm) set in 1954. Seattle airport also set low temperature records on both Jan 17 and 18. Olympia, Washington airport received 11 in (28 cm) of snowfall on January 18, breaking the previous record of 4.5 in (11.4 cm) set in 1954. In southeastern Washington, La Crosse received 12 in (30.5 cm) of snowfall in 24 hours, the most snowfall in a 24-hr period at this location since records began in 1931. Storm snowfall totals in mountains of the Northwest ranged from 30-50 inches (76.2-127 cm) Several daily precipitation records were broken throughout the storm period throughout Washington northern Idaho, and western Montana.
January 19-20: Washoe Drive Fire near Reno, Nevada: High winds gusting to 70-85 mph (31-38 m/s) combined with extremely dry conditions allowed a wildfire to grow extremely rapidly south of Reno, Nevada on the afternoon on January 19th. The area had been without significant precipitation for over 6 months, creating dangerous fire conditions. The fire covered roughly 6 square miles (15.5 square km) and destroyed 29 homes in just a few hours The arrival of very heavy precipitation (about 1” / 25 mm) and slackening winds on January 20th allowed firefighters to gain control of the fire by late evening.