The Record Warmth of March 2012

 

 

March 2012 will be remembered for its record-breaking warmth, particularly across the Upper Midwest. Long stretches of record highs and record warm lows were set, a lot of them significantly (10 degrees or more), including all-time March records.

Record warmth was not only found in the Upper Mississippi River Valley, but across the entire Midwest.  According to the Midwestern Regional Climate Center, "The average temperature for the nine-state Midwest region was 50.3 degrees Fahrenheit, which broke the previous record of 46.9 degrees set over 100 years ago in 1910.  Each of the nine Midwest states also set statewide records for the warmest March.  Statewide records go back to 1895, and the existing records were all from the early to mid-20th century. 

March 2012 Temperature Anomalies

Daily Temperature Anomalies
for March 2012

(Courtesy of the Midwestern
Regional Climate Center
)

Preliminary statewide average temperatures for March:

  • Illinois - 54.9 degrees (previous record 51.6 in 1946)
  • Indiana - 54.4 degrees (previous record 52.1 in 1946)
  • Iowa - 51.3 degrees (previous record 47.7 in 1910)
  • Kentucky - 57.6 degrees (previous record 55.6 in 1945)
  • Michigan - 44.5 degrees (previous record 41.2 in 1945)
  • Minnesota - 42 degrees (previous record 40.6 in 1910)
  • Missouri - 57.7 degrees (previous record 55.0 in 1910)
  • Ohio - 51.5 degrees in Ohio (previous record 49.5 in 1946)
  • Wisconsin - 45.3 degrees (previous record in 40.7 in 1910)
  • Throughout the month, over 6,400 daily record temperatures were set or tied (including both warmest minimum and maximum temperature), with over 650 of them also setting records for the warmest temperature for any day in March.  A majority of the records were set during the middle of the month, from the 14th through the 24th of March, when hundreds of records fell each day.

    March average temperatures ranged from 10 degrees above average in Kentucky to 17 degrees above average in northwest Iowa, southern Minnesota, and western Wisconsin.  During the record-breaking period from March 14 to 24, temperature departures ranged from at least 13 degrees above average in southwest Missouri to just over 29 degrees above average in central Wisconsin and northern Michigan. 


    Why So Warm?

    The culprit was an unseasonably warm pattern over the Upper Mississippi River Valley region that took hold on March 10th. Aiding in this stretch was the lack of snow cover along and south of Interstate 94. The warmth and humidity intensified over the weekend of the 17th and 18th, in response to a deepening low pressure system over Montana. A slow cool down then ensued as more clouds and occasional precipitation moved across the region, associated with the low pressure system's cold front. Toward the end of the month, a slight warm up into the 70s set some new records, but temperatures dropped back to normal readings for the last few days of the month.


    All-Time Warmest March Across The Upper Mississippi River Valley

    The long stretch of well above normal warmth from the 10th to the 22nd, where records were being set nearly every day, helped to propel the average temperature for the month of March to new records.
    All-Time Warmest March
      La Crosse, WI Rochester, MN
    Ave Temperature 50.4 49.1
    Previous Record 47.1 (1878) 42.9 (1910)
    Normal 34.5 32.4
    • La Crosse Municipal Airport had an average temperature of 50.4 degrees.  This was 15.9 degrees above the 1981-2010 March normal of 34.5 degrees.  This easily surpassed the previous record of 47.1 degrees in 1878.  March of 2012 was even 2.6 degrees warmer than the 1981-2010 April average.  Only 30 April's were warmer than this March (monthly records date back to 1873: 139 April's).
    • Rochester International Airport had an average temperature of 49.1 degrees.  This was 16.7 degrees above the 1981-2010 March normal of 32.4 degrees.  This smashed the previous record by over 6 degrees (42.9 degrees in 1910).  March of 2012 was even 4.4 degrees warmer than the 1981-2010 April average.  Only 13 April's were warmer than this March (monthly records date back to 1886:  96 April's).

    In addition to the record warmth at both La Crosse and Rochester, March of 2012 was the warmest at the following cooperative observing sites:

    Northeast Iowa...

                           2012 March       Previous Record      Records
                           Avg. Temp.          for March          Began
                           ----------       ---------------      -------
    Cascade              50.1 degrees*   43.3 degrees in 1973     1948
    Charles City         49.8 degrees
        44.4 degrees in 1910     1893
    Cresco 1NE           48.0 degrees    42.2 degrees in 1946     1893
    Decorah              50.9 degrees  
      43.7 degrees in 1910     1893
    Elkader              47.5 degrees
    *   45.8 degrees in 1910     1893
    Fayette              48.8 degrees 
      45.0 degrees in 1910     1893
    Guttenberg Dam 10    51.4 degrees
       43.7 degrees in 1973     1937
    New Hampton          47.3 degrees
    *   44.2 degrees in 1910     1897
    Oelwein+             48.5 degrees 
      44.8 degrees in 1945     1923
    Osage                48.1 degrees
       46.5 degrees in 1910     1899
    Waukon               46.8 degrees
    *   42.4 degrees in 1945     1934

    Southeast Minnesota...

                           2012 March       Previous Record      Records
                           Avg. Temp.          for March          Began
                           ----------       ---------------      -------

    Austin WWTP          46.4 degrees
        43.8 degrees in 1946     1938
    Byron                46.0 degrees    38.2 degrees in 2000     1993
    Caledonia            46.9 degrees
    *   41.0 degrees in 1973     1893
    Grand Meadow         45.8 degrees    44.5 degrees in 1910     1891
    Preston              48.6 degrees
       40.6 degrees in 1973     1953
    Theilman             48.0 degrees
    *   39.6 degrees in 2010     1963
    Winona               49.1 degrees    46.5 degrees in 1910     1893
    Zumbrota             47.1 degrees    44.6 degrees in 1910     1896


    Western Wisconsin...

                           2012 March       Previous Record      Records
                           Avg. Temp.          for March          Began
                           ----------       ---------------      -------

    Alma Dam 4           49.6 degrees
    *   41.2 degrees in 2000     1939
    Blair                47.4 degrees    45.4 degrees in 1910     1896
    Friendship           47.7 degrees    41.7 degrees in 1945     1930
    Genoa Dam 8          51.0 degrees
        44.5 degrees in 1946     1939
    La Crosse NWS        49.1 degrees    39.9 degrees in 2000     1996
    Lancaster 4WSW       50.7 degrees
        45.6 degrees in 1945     1893
    Lone Rock Tri Co AP  50.6 degrees
        42.6 degrees in 1973     1948
    Lynxville Dam 9      51.6 degrees
        45.2 degrees in 1945     1940
    Mauston 1SE          48.7 degrees
       40.7 degrees in 1973     1905
    Medford              43.2 degrees    41.1 degrees in 1910     1893
    Necedah 2SE          47.1 degrees    41.4 degrees in 2000     1954
    Neillsville 3SW      46.0 degrees    39.0 degrees in 1973     1893
    Owen 3W              44.3 degrees
    *   37.7 degrees in 2000     1947
    Prairie du Chien     50.5 degrees
        45.8 degrees in 1945     1893
    Richland Center      48.5 degrees
       44.1 degrees in 1945     1908
    Soldiers Grove       49.1 degrees    39.2 degrees in 2010     2010
    Sparta               49.0 degrees
    *   42.5 degrees in 1945     1893
    Trempealeau Dam 6    50.6 degrees
       41.4 degrees in 2000     1937
    Viroqua              46.5 degrees
    *   45.9 degrees in 1910     1893

    * Missing 1 to 3 days of temperature data, so the monthly temperature average is preliminary.


     Listing Of Daily Temperature Records Set During March 2012:

    La Crosse   Rochester
    High Temperature   High Temperature
    Date Record Previous   Date Record Previous
    March 11th 67 66 in 2006   March 11th 63 60 in 1990
    March 14th 75 68 in 1990   March 13th 66 63 in 1990
    March 15th 71 68 in 1995 & prev   March 14th 74 70 in 1910
    March 16th 79 75 in 1930   March 15th 73 67 in 2003
    March 17th 83 78 in 1894   March 16th 78 73 in 1930
    March 18th 80 71 in 1903   March 17th 81 66 in 1930
    March 20th 74 71 in1918   March 18th 80 60 in 1910 & prev
    March 22nd 77 73 in 1994   March 19th 77 69 in 1910
    March 27th 78 77 in 1910        
                 

     

    La Crosse   Rochester
    Warmest Low Temp   Warmest Low Temp
    Date Record Previous   Date Record Previous
    March 15th 44-tied 44 in 1898   March 14th 49 44 in 1973
    March 17th 62* 51 in 1894   March 16th 48 43 in 1990
    March 18th 59 48 in 1968   March 17th 58 45 in 1966
    March 19th 62* 59 in 1921   March 18th 61 46 in 1968
    March 20th 57 45 in 1918   March 19th 62* 38 in 1976
    March 21st 57 46 in 1946 & prev   March 20th 58 42 in 1918
    March 22nd 57 47 in 1910   March 21st 57 44 in 1946
    March 23rd 58 49 in 1987   March 22nd 59 40 in 2000
    March 24th 54-tied 54 in 1910   March 23rd  55  49 in 1920 
            March 24th  54  52 in 1945 
                 
    * Warmest low on record for March

     

    La Crosse Warmest Daily Ave Temperature

     

    Rochester Warmest Daily Ave Temperature

               
     
    New Record
    Previous Record
     
    New Record
    Previous Record
               
      54.5 on March 11th 53.5 in 1977   50.0 on March 11th 49.0 in 1977 & 1990
     
    60.0 on March 14th 58.5 in 1990
     
    61.5 on March 14th 52.0 in 1990
     
    57.5 on March 15th 53.5 in 1927
     
    57.0 on March 15th 51.0 in 2003
      61.5 on March 16th 60.5 in 1930
     
    63.0 on March 16th 58.0 in 1930
      72.5 on March 17th 64.5 in 1894
     
    69.5 on March 17th 54.5 in 1966
      69.5 on March 18th 57.5 in 1903
     
    70.5 on March 18th 49.5 in 1918 & 1968
      68.5 on March 19th 67.5 in 1921
     
    69.5 on March 19th 53.0 in 1918 & 1976
      65.5 on March 20th 58.0 in 1918
     
    63.5 on March 20th 56.5 in 1918
      65.5 on March 21st 58.5 in 1938
     
    61.5 on March 21st 57.0 in 1918
     
    67.0 on March 22nd 57.5 in 1910
     
    67.0 on March 22nd 57.0 in 1938
         
     
    63.0 on March 23rd 57.0 in 1945
               

    La Crosse Highest March Dew Point

     

    Rochester Highest March Dew Point

               
     
    New Record
    Previous Record
     
    New Record
    Previous Record
               
     
    61 on March 17th 61 on March 23, 1936   62 on March 16th 56 on March 25, 2007
      62 on March 20th 61 on March 17, 2012
     
    62 on March 17th - tied  62 on March 16, 2012
               


    March 2012 Temperatures In La Crosse,WI & Rochester, MN:

    Record March warmth for 2012 for La Crosse
    Record warmth for March 2012 in Rochester
    La Crosse, WI
    High and Low Temperatures
    Rochester, MN
    High and Low Temperatures

    Other Interesting Climate Factoids:

    La Crosse, WI

    • On March 20th at 1:53 a.m. CDT, the dew point at the La Crosse Municipal Airport climbed to 62 degrees.  This breaks the previous record of 61 degrees set on March 17, 2012 and March 23, 1936 for the highest March dew point.  Dew point records for La Crosse date back to 1933.
    • The 83 degree high temperature on March 17th was the earliest occurrence of an 83 degree day in a year. The high temperature was 1 degree shy of the all-time March temperature of 84 set on the 29th of 1986.
    • Between March 17th and March 20th, average temperature departures from normal were 30 or more degrees.  March 17th saw the largest departure from normal, a whopping 38 degrees!
    • Between March 14th and 22nd, 70 degree or higher temperatures were observed (9 consecutive days). This broke the longest string of 70 degrees or higher temperatures in March. The previous record occurred between March 23rd and 29th of 1910.

    Rochester, MN:

    • On March 16th at 11:54 a.m. CDT and March 17th from 10:54 a.m. through 12:54 p.m., the dew point at the Rochester International Airport climbed to 62 degrees.  This surpassed the previous March record of 56 degrees set on March 25, 2007.  Prior to this year, the earliest 60 degree dew point was April 24th in 1990.  Dew point records for Rochester date back to 1948.
    • The 81 degree high temperature on March 17th was the earliest occurrence of an 80 degree day in a year. The previous record was March 24th of 1910.  The high temperature was 1 degree shy of the all-time March temperature of 82 degrees, also set on the 24th in 1910.
    • Between March 17th and March 20th, average temperature departures from normal were 30 or more degrees. March 18th saw the largest departure from normal, a whopping 38 degrees!
    • Between March 14th and 19th, 70 degree or higher temperatures were observed for 6 consecutive days. This is the second longest string of 70 degrees or higher temperatures in March. The record is 7 days between March 24 and 30th of 1910.

    Mississippi River:

    • Water temperatures responded dramatically to the unprecedented warmth as well. At La Crescent Dam 7, the water temperature rose from 36 degrees at 7 a.m. on March 10th to 50 degrees at 7 a.m. on the March 20th.  The water temperature topped out at 52 degrees on March 26th.

      March 2012 Mississippi River Temperatures at La Crescent, MN

      Mississippi Water Temperatures
      at La Crescent, MN during Match 2012

    Phenology:

    Phenology is the study of periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate.

    The record warmth resulted in the growing season starting well ahead of normal.  Soil temperatures quickly climbed from 31 degrees on March 9th to 58 degrees on March 18th.  They topped out at 59 degrees on March 22nd.  As clouds and precipitation moved into the area during the last week, they cooled off into the mid and upper 40s.

     NWS La Crosse 2" Soil Temperatures for March 2012

    NWS La Crosse 2" Soil Temperatures for March 2012


    In addition, the accumulated growing degree days climbed rapidly during the month.  Areas along and north of the Interstate 94 corridor saw anywhere from 100 to 150.  Meanwhile the remainder of the area accumulated between 150 and 210.  Normally, we do not start accumulating growing degree days until after April 1st.  The image below illustrates how the growing degree days quickly accumulated from March 13th through March 27th.

    March 2010 Growing Degree Days

    With the unusually warm soils and well above normal growing degree days, the growing season is well ahead of schedule.  Forsythia bushes and spring flowers (crocuses, hyacinths, and tulips) were flowering anywhere from two weeks to a month ahead of schedule.  Meanwhile fruit trees and rose bushes were at least a month to 6 weeks ahead of schedule.  There were even some mushrooms at the end of March (usually not seen until May).  The pictures below are from West Salem, WI.

    March 18, 2012:

    Rose bush beginning to leaf out on March 18, 2012  Forsythia bush flowering on March 18, 2012  Magnolia bush flowering on March 18, 2012
     Rose bush beginning to leaf out  Forsythia bush flowering  Magnolia bush flowering
    Crocuses blooming on March 18, 2012 Crocuses blooming on March 18, 2012 Spring flowers blooming on March 18, 2012
    Crocuses blooming Crocuses blooming Spring flowers blooming

    March 26, 2012:

    Rose bush fully leafed out on March 26, 2012  Forsythia bush fully leafed out on March 26, 2012  Bleeding Hearts flowering on March 26, 2012
     Rose bush fully leafed out Forsythia bush fully leafed  Bleeding Hearts flowering
    Double Flowering Dogwood beginning to bloom on March 26, 2012 Hyacinths blooming on March 26, 2012 Azalia bush in full bloom on March 26, 2012
    Crocuses blooming Hyacinths blooming Azalia bushes blooming

    March 31, 2012:

    Mushrooms on March 31, 2012  Double Flowering Dogwood in full bloom on March 31, 2012  Weeping Dogwood about ready to bloom on March 31, 2012
     Mushrooms  Double Flowering Dogwood
    in full bloom
     Weeping Dogwood about
    ready to bloom
    Blueberry bush getting ready to leaf out on March 31, 2012 Maple tree beginning to leaf out on March 31, 2012 Tulips on March 31, 2012
    Blueberry bush getting
    ready to leaf out
    Maple tree beginning to leaf out Tulips


    Additional Climate Information:

    • Climate records for La Crosse, WI date back to 1873.
    • Climate records for Rochester, MN date back to 1886.

     


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