AgWeatherNet March 2012 Weather Review for Washington

March Goes Out Like a Lion in 2012

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

Overview
In contrast to the conventional wisdom, March ended with a continuation of the stormy conditions that dominated the weather during the middle and latter part of the month. Temperatures were slightly below normal overall due to cloud cover and periodic intrusions of cold, upper level air from the Pacific Ocean. It featured a variety of active weather, including rain, snow, and wind. March was generally wetter than normal, with record rainfall in some regions. Long Beach received more than fifteen inches of rain for the month. Very wet weather also occurred in eastern and northern Washington during the final week of the month. Western Washington’s wet weather was spread throughout the month, such that there were no long spells of dry weather. In fact, Long Beach experienced only five rain-free days during March. However, typically dry areas in south central Washington recorded less than one inch of precipitation for the month. Western Washington day-time temperatures were cool during the month due to cloud cover and precipitation from periodic storms. An unusually strong late season low pressure system delivered wind and even snow to coastal regions on March 12th. Another late season snow fell on March 21st in eastern Washington from Pullman to Spokane. There were several cold nights during the month, as most locations fell below freezing and the coldest locations fell to around 20 degrees. There was also an absence of any extended warm and dry period of the type that can normally occur during the month of March. A positive aspect of the wet weather in the lowlands was that the mountain snow pack continued to improve during March, and reached above normal levels in the Cascade Mountains as of March 31, 2012.

March 2012 Precipitation Bar Graph for Long Beach

A trough of low pressure became established west of the Washington coast early in the month, and was responsible for steering moist and windy weather systems into the region from the southwest. Temperatures were below normal to a greater extent in western Washington and during the daytime, which is typical for an active weather pattern, as was observed in March. Western Washington was wet for the much of the month, and was nearer to the source of the cold air in the North Pacific Ocean. Cloud cover and an absence of hot days contributed to the cool daily high temperatures. Low temperatures were only slightly below normal since the effect of the cool air masses was balanced by the relative lack of clear and stable nights when efficient radiative cooling could have occurred. For example, Wenatchee, which normally does not develop a strong night-time inversion layer, was cooler than normal during the day and at night. By contrast, Moxee was cooler than normal in the day, but warmer than normal at night. Moxee often experiences cold and stable conditions at night, such that the cloudy and windy weather more strongly affect low temperatures at Moxee than at other locations.

Unseasonable warmth continued in March across much of the contiguous United States. Many locations in the northern US from North Dakota to the Northeast had high temperatures in the 80s during the middle of the month. On March 18th, the daily high temperature at Marquette, MI was 81 degrees. Overall, the daily average temperature was 41 degrees above normal for the date, and the monthly average temperature was nearly 17 degrees above normal! On the same day, International Falls, MN (“The Ice Box of the Nation”) had an all time monthly record high temperature of 79 degrees. By contrast, an unusually late snowstorm on March 21st dumped heavy snow on parts of the southern Willamette Valley in the Eugene, OR area. Some lowland areas received over six inches of snow, while mountain locations received up to 3 feet of snow.

March 2012 Daily Average Temperatures (°F)
Location (Period of Record) Maximum Anomaly Minimum Anomaly Mean Anomaly
Prosser (WSU IAREC; 1989-2012)
55.3
-1.1
33.6
-0.7
44.8
-0.6
Moxee (1989-2012)
53.3
-2.2
30.0
0.9
42.2
-0.4
Mt. Vernon (WSU NWREC; 1994-2012)
49.2
-2.5
37.3
-0.8
43.1
-1.5
Wenatchee (WSU TFREC; 1994-2012)
52.0
-1.9
32.1
-0.8
41.8
-1.5
Tri-Cities (1995-2012)
57.0
-1.1
35.3
-0.1
46.5
-0.3
Walla Walla (1993-2012)
54.0
-0.7
36.4
-0.3
45.5
-0.1
Royal City East (2008-2012)
53.5
NA
34.7
NA
43.9
NA
Pullman (2008-2012)
46.6
NA
31.9
NA
38.7
NA
Long Beach (WSU Long Beach; 2005-2012)
49.0
NA
37.0
NA
42.9
NA

March Weather
Early March
March began with seasonally cool temperatures, but warm weather quickly followed during the first weekend of the month, as highs in south central Washington rose into the 60s. A weather system on March 5th brought rain to western Washington and wind to eastern Washington. Cold air and clear skies in the wake of the storm allowed temperatures to fall to near 20°F in some places. High pressure caused warmer and dry weather until March 9th.

Mid March

A weak storm delivered rain to western Washington on March 9th, and ushered in a wetter pattern that would persist for the rest of the month. Additional rain fell over the weekend of the 10th/11th in western Washington, and windy conditions were present in eastern Washington, as a trough of low pressure became established off the Washington coast. A strong low pressure system moved northward and bombed (intensified rapidly) off the Washington coast on March 12th, and caused strong winds in western Washington. Several inches of snow fell in coastal areas on the night of the 12th due to the presence of very cold air aloft. It was unusually late in the winter season for such a strong and cold surface low pressure system to affect the Northwest. Two wet and warmer storms that moved through Washington on March 14th and 15th were followed by unsettled but somewhat drier weather from March 16th to 18th, as a trough of low pressure carved itself over the west coast, and pushed the active weather south of the region. Showers and cool weather continued in western Washington, with wind in eastern Washington and snow in the mountains thanks to the cold air aloft. Clear skies and a cold air mass on the morning of March 19th sent temperatures down to 20 degrees in cold spots of south central Washington.

Late March

Another storm on March 20th brought more rain, wind, and mountain snow to the area. Strong southerly winds caused much warmer morning temperatures on the 20th compared to the 19th. Snow fell in parts of eastern Washington on the night of the 21st and into the morning of the 22nd, with up to seven inches falling in parts of northeastern Washington. Overall, the heaviest lowland snow occurred in far eastern Washington toward the Pullman and Spokane areas. Cloud cover and a cool air mass on March 21st caused unseasonably cool day-time temperatures in the upper 30s and low 40s in southern Washington. The high temperatures were in the 30s in the Pullman and Spokane areas, and in the low 40s in south central Washington. Highs ranged from the mid to upper 30s in the Columbia River Gorge from Hood River to Vancouver. A stalled front located over central Oregon caused rising air to cool just north of the front, while precipitation falling into relatively dry air and evaporating further enhanced the cooling. These additional factors led to the local, artificial cooling of an air mass that was not of arctic origin, and caused unseasonably cold late March temperatures. Warmer temperatures occurred during the weekend of the 24th/25th, as highs reached the 60s across much of central Washington under southerly flow aloft. Weak storms began to affect the region again on March 26th, as around three quarters of an inch of rain fell in 24 hours in the Pullman area. Rain even fell in arid central Washington on March 27th, as southerly flow temporarily nullified the Cascade rain shadow effect. More than one half inch of rain fell in many parts of north central Washington. Unfortunately, March went out like a lion in 2012, as a series of moist storms delivered heavy rain to the lowlands and both heavy rain and snow to the mountains during the final days of the month. Flooding occurred at the end of the month in both western and eastern Washington.

March 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 March 2012 Temperature Time Series Graph for WSU Pullman
March 2012 Temperature Time Series Graph for WSU Long Beach March 2012 Temperature Time Series Graph for WSU Mt. Vernon

March-By the Numbers
The average March temperature at Prosser (WSU IAREC) was 44.8°F, which was 0.6 degrees below the average of 45.4°F. The average high temperature was 55.3°F, which was 1.1 degrees below normal, while the average low temperature was 33.6°F, which was 0.7 degrees below normal. The warmest temperature of the month was 71.3°F on March 9th, while the coldest temperature of the month was 22.0°F on March 19th. The coolest high temperature was 41.4°F on March 21st, while the warmest low temperature was 46.5°F on March 15th. The warmest day of the month was March 15th, with an average temperature of 53.3°F, while the coldest day of the month was March 6th, with an average temperature of 34.6°F. 0.78 inches of precipitation fell during the month, while the average wind speed was 6.9 mph.


March 2012 Recent Temperatures Graph

Notable March Events:
  • March 9th: The temperature at WSU Tri-Cities rose to 72.6 degrees.
  • March 12th: 3 inches of rain fell at Long Beach.
  • March 19th: The temperature at Moxee fell to 17.7 degrees.
  • March 20th: Winds gusted to 56 mph at St. John.
March 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)
71.3
3/9/2012
22.0
3/6/2012
79.1
3/31/2011
11.5
3/2/1993
Moxee (1989-2012)
69.4
3/9/2012
17.7
3/6/2012
76.2
3/30/2003
9.7
3/1/1993
Mt. Vernon (WSU NWREC; 1994-2012)
61.0
3/27/2012
25.6
3/7/2012
79.8
3/29/2004
20.3
3/1/2007
Wenatchee (WSU TFREC; 1994-2012)
64.3
3/25/2012
24.4
3/1/2012
76.3
3/28/1994
15.6
3/2/1995
Tri-Cities (1995-2012)
72.6
3/9/2012
21.8
3/7/2012
78.7
3/30/2003
16.9
3/12/2009
Walla Walla (1992-2012)
71.0
3/9/2012
27.2
3/7/2012
78.4
3/30/2003
6.3
3/1/1993
Royal City East (2008-2012)
69.0
3/9/2012
26.3
3/7/2012
69.0
3/9/2012
16.3
3/10/2009
Pullman (2008-2012)
64.5
3/31/2012
24.0
3/7/2012
65.6
3/16/2010
-6.2
3/11/2009
Long Beach (WSU Long Beach; 2005-2012)
64.9
3/8/2012
25.4
3/7/2012
70.4
3/13/2005
25.4
3/11/2009

Agriculture Report
A return to wetter weather in March led to standing water in many western Washington fields. Christmas tree growers welcomed the cool and wet weather as they finished planting the fields. Pruning was completed in many berry fields, while a few frosty nights caused concern for berry growers in the Bellingham area. In central Washington, preparation for spring continued in the form of planting, pruning, and spraying. Seeding for spring wheat began, while winter wheat continued to look good in Grant County. Delayed dormant sprays were applied in Yakima County to manage overwintering insect pests. Apricots had already bloomed as of March 26th. Pear psylla was active in Chelan County, and bloom development was about 4 days behind average. In eastern Washington, increased precipitation in March helped but did not completely alleviate the low soil moisture content. Conditions were generally wetter than normal during March in Washington, while temperatures were somewhat below normal.

This Month in History
On March 2, 1993, the temperature fell to 11.5 degrees at Prosser (WSU IAREC). The average monthly temperature was 3.5 degrees below normal, and March marked the third consecutive month of record cold to begin 1993.

Climate Outlook
The Climate Prediction Center (CPC) outlook calls for slightly enhanced odds of cooler and wetter than normal conditions in April and throughout the spring. By late summer, the outlook tilts toward warmer and drier than normal conditions.

Washington State University