AgWeatherNet January 2012 Weather Review for Washington

Calm Conditions Early Transitioned to Active Winter Conditions around Mid Month

Nic Loyd, Meteorologist, 509-786-9357
Gerrit Hoogenboom, Director, 509-786-9371

Overview
January behaved much like Dr. Jekyll and Mr. Hyde, as unseasonably calm conditions for the first half of the month quickly transitioned into active winter weather for 7 to 10 days during the middle to latter part of January. This period of active weather began on January 14th and included heavy rain, heavy snow, ice, wind, flooding, and extreme low temperatures. A high impact winter storm on January 18th brought heavy snow to much of Washington State. 17 inches of snow fell near Centralia on the 18th, while 6 inches of snow fell along parts of the east slopes of the Cascades. Heavy ice accumulations on the 19th caused hazardous travel across much of the Puget Sound region and in the Tri-Cities area, while additional heavy snow fell along the Cascade east slopes. Cold northeast winds caused bitter wind chills in the Bellingham area. As temperatures warmed from the southwest, heavy rainfall and rapid snowmelt led to flooding in parts of western Washington. Although January temperatures were generally near to slightly below average in Washington, there was significant variability during the month and between regions. High temperatures were near to above normal, while low temperatures were below normal. Areas in parts of southern Washington recorded above normal temperatures, especially near Walla Walla, while other areas were below normal. The period of January 14th to 23rd was generally cooler than normal and included a few days of modified arctic air in parts of the state, while the remainder of the month was milder than normal.

January 2012 Daily Average Temperatures (°F)
Location (Period of Record) Maximum Anomaly Minimum Anomaly Mean Anomaly
Prosser (WSU IAREC; 1989-2012)
42.5
2.8
24.7
-2.9
33.7
0.3
Moxee (1989-2012)
39.7
0.7
19.4
-4.2
29.4
-1.7
Mt. Vernon (WSU NWREC; 1994-2012)
46.1
-0.1
34.2
-1.1
40.1
-0.7
Wenatchee (WSU TFREC; 1994-2012)
36.7
0.3
21.6
-2.5
28.7
-1.0
Tri-Cities (1989-2012)
42.9
1.4
24.8
-3.7
33.7
-1.2
Walla Walla (1992-2012)
45.7
3.4
28.9
-1.6
37.1
1.0
Royal City East (2008-2012)
38.9
NA
24.6
NA
31.2
NA
Pullman (2008-2012)
38.9
NA
26.3
NA
32.8
NA

January Weather
An Uneventful Early January
2012 began with generally uneventful weather. Rain fell at times in western Washington during the first week of the year, with the most significant precipitation falling on January 4th. Eastern Washington was mostly dry during the first week of the year. Locations near Walla Walla recorded temperatures in the mid to upper 60s on Wednesday, January 4th. A cold front brought slightly cooler temperatures by January 6th. With the exception of a weak system on Monday, January 9th that delivered a bit of rain to western Washington, high pressure continued to dominate through much of the second week of 2012, continuing the unseasonably calm trend established at the end of 2011. Temperatures were generally above normal, while dry and snow free conditions prevailed in the low lands.

A Major Winter Storm in Mid January
A major pattern change occurred on January 14th, as a trough of low pressure brought cold air aloft into Washington. Much needed snow fell in the Cascades, while scattered rain and snow showers occurred in western Washington. Light to moderate snow accumulations occurred on January 16th and 17th in western Washington.

The strongest in a series of moist systems reached the area on January 18th, bringing heavy snow to western Washington, along with very heavy snow in the mountains. The most significant amounts occurred in interior southwest Washington, as 17 inches of snow fell in the Centralia area. Around 6 inches of snow fell in the Yakima area. Very cold temperatures in northern Washington were the result of an arctic front that was pulled south of the Canadian Border by strong and warm surface low pressure approaching the coast on the morning of Wednesday, January 18th. Temperatures from Bellingham to Omak fell into the single digits. Meanwhile, southwest Washington near Long Beach quickly warmed to near 50 degrees with heavy rain. The heavy snow fell in parts of central Washington where the warm, moisture laden air met with the cold, dry arctic air.

Another weather system on Thursday, January 19th brought more snow to parts of Washington from Yakima to Seattle, while a wintry mix that included freezing rain fell in southern parts of the state. Heavy accumulations of ice occurred in parts of the Puget Sound region as well as in the Tri-Cities area. Precipitation in western Washington finally changed to rain on Friday, January 20th. However, concerns shifted from heavy snow and ice to heavy rain and urban flooding. Meanwhile, areas in the northern part of eastern Washington and areas near the east slopes of the Cascades received additional snowfall. Rain fell on Saturday morning in western Washington, while more snow fell in the mountains. Most areas east of the Cascades received a reprieve from the winter weather. Many areas in southeastern Washington near the Tri-Cities and Walla Walla mixed out the remainder of the cold air mass and warmed well into the 40s, while northern areas remained in the 30s. Another storm system on Sunday, January 22nd provided rain for western Washington, and more snow for the north part of eastern Washington and the east slope valleys. Most areas finally experienced dry weather on Monday, January 23rd, although areas from Yakima to Wenatchee lay buried under 12 or more inches of snow.

Quieter Weather Returns in Late January
Beginning on Tuesday, January 24, a couple of warmer weather systems brought more rain to western Washington, and even to parts of eastern Washington. Rising freezing levels caused snow to change to rain especially in the southern and central Cascades until a cold front brought lower freezing levels on Thursday, January 26th. Dry weather ended with a warm storm system on January 29th that brought rain to western and parts of eastern Washington. Breezy winds caused temperatures to surpass 60 near Walla Walla and the Tri-Cities. A cooler storm system delivered a bit of snow to the Cascades on Tuesday, January 31st. Overall, January was a month featuring two distinct patterns. Somewhat calm and mostly dry conditions prevailed during the first half and the last few days of the month. However, this calm period was punctuated by a seven to ten day period of exciting winter weather that featured snow, rain, ice, wind, flooding, and cold temperatures.

January 2012 Daily Temperatures
2012 Temperature Time Series Graph for Prosser 2012 Temperature Time Series Graph for Moxee
2012 Temperature Time Series Graph for Wenatchee 2012 Temperature Time Series Graph for Tri-Cities
2012 Temperature Time Series Graph for Walla Walla January 2012 Temperature Time Series Graph for WSU Pullman
January 2012 Temperature Time Series Graph for WSU Long Beach January 2012 Temperature Time Series Graph for WSU Mt. Vernon

January-By the Numbers
Prosser (WSU IAREC) was 0.3 degrees above average in January, with an average temperature of 33.7°F. The average high temperature of 42.5°F was 2.8 degrees above average, while the average low temperature of 24.7°F was 2.9 degrees below average. The warmest temperature of the month was 57.5°F on January 29th, while the coldest temperature of the month was 14.2°F on January 13th. These values are typical of the expected range of January temperature extremes in Prosser. 0.78 inches of precipitation fell at Prosser (WSU IAREC), and the average wind speed was 4.8 mph. The coolest daily high temperature was 23°F on January 19th, and the warmest daily low temperature was 37.5°F on January 30th. The average temperature at Wenatchee of 28.7°F was one degree below average, while the average temperature at Pullman of 32.8°F was slightly above average.


January 2012 Recent Temperatures Graph

Notable January Events:
  • January 4th: The temperature at Walla Walla rose to 68 degrees.
  • January 18th: 14+ inches of snow fell in the Centralia area in interior southwestern Washington.
  • January 19th: Parts of the eastern Puget Sound Lowlands accumulated an inch or more of ice.
  • January 23rd: 10 day snowfall totals in the Cascades measured five to eight feet.
January Temperature Extremes (°F)
  Observed in 2012 Record Monthly Extremes
Site (Period of Record) Warmest Date Coldest Date Warmest Date Coldest Date
Prosser (WSU IAREC; 1989-2012)
57.5
1/29/2012
14.1
1/13/2012
65.4
1/31/1995
-11.9
1/31/1996
Moxee (1989-2012)
54.3
1/4/2012
6.7
1/23/2012
60.7
1/26/2003
-22.7
1/31/1996
Mt. Vernon (WSU NWREC; 1994-2012)
57.6
1/4/2012
16.6
1/16/2012
64.0
1/11/2010
8.8
1/4/2004
Wenatchee (WSU TFREC; 1994-2012)
55.2
1/30/2012
10.4
1/19/2012
58.6
1/23/2011
-13.4
1/30/1996
Tri-Cities (1989-2012)
57.5
1/29/2012
10.3
1/12/2012
65.1
1/26/2003
-9.6
1/31/1996
Walla Walla (1992-2012)
67.9
1/4/2012
17.8
1/19/2012
70.9
1/19/2005
-13.0
1/31/1996
Royal City East (2008-2012)
53.8
1/4/2012
11.4
1/20/2012
60.6
1/16/2011
4.5
1/4/2009
Pullman (2008-2012)
51.2
1/4/2012
16.1
1/15/2012
53.5
1/16/2011
-17.5
1/26/2009

Agriculture Report
Winter wheat is still in good condition. However, above normal spring precipitation will be required to maintain the crop. The powerful winter storm on January 18th/19th led to some tree and farm damage, especially in western Washington. Vegetables looked better than usual, and the oyster and clam harvest continued (National Agricultural Statistics Service).

This Month in History
On January 31st, 1996, the temperature at Prosser (WSU IAREC) fell to a January record low of -12 degrees at the beginning of one of the most severe arctic air outbreaks in recent decades in the Northwest.

Climate Outlook
The official CPC forecast for the remainder of February is for normal conditions, and then a slightly increased likelihood of below normal temperatures and above normal precipitation for the spring. La Niña conditions are expected to end by late spring as we transition to neutral conditions.

Washington State University