Spring Climate Summary 2011

Overview

The 2011 spring season (March through May) for Southwest Lower Michigan was near normal for temperature, but well above normal for precipitation. Snowfall was, like 2010, well below normal. The severe storm episode frequency was above normal.

 
TABLE 1. Reported temperature, precipitation and snowfall amounts for the spring of 2011 at the primary climate stations in Southwest Lower Michigan. Normals are computed from 30-year averages from 1971-2000.
 

Spring 2011 Temperatures for Southwest Lower Michigan:

 

The warmest location in Southwest Michigan during the spring of 2011 was the Battle Creek Kellogg Airport with an average temperature of 47.2 degrees, which was 1 degree above normal there. The coldest location in Southwest Michigan was Albion with an average temperature of 37.2 degrees, which was 9.8 degrees below normal.

It would appear from Table 1 (above), temperatures averaged above normal for the spring of 2011. However, it should be pointed out that while two of the three stations in Table 1 were at or warmer than 0.5 degrees above normal, most of our 24 stations used for the area mean temperature were near or colder than normal. Only four were at least 0.5 degrees above normal. To be in the above normal class (top 1/3 warmest), the seasonal mean for the spring of 2011 would have to be warmer that 45.9 degrees. The mean for the spring of 2011 was 44.8 degrees, which is 0.4 degrees below normalMeanwhile, there were 10 stations that were more than 0.5 degrees below normal. It was mostly the primary climate sites listed on the table above that were on the warm side of normal.

            The three temperature summary charts below (Figs 1,2 and 3) show daily fluctuations for the spring of 2011. We had 21 days (23%) that were at or more than 5 degrees warmer than normal.  There were 22 days (24%) with daily mean 5 or more degrees colder than normal. The daily temperature pattern for the spring of 2011 was typical of spring in Southwest Michigan over the past 10 years.

 

 Fig. 1. Spring 2011 observed daily maximum and minimum temperatures. Please see blue text above for a description of the figure.

The high temperature of 85 degrees on the 10th of April is the earliest ever occurrence of 85 degrees for Grand Rapids. During the spring of 2011, there were six days with highs at or warmer than 85 degrees. In 2010, there were seven consecutive days with highs at or above 85 degrees. In a normal spring in Grand Rapids, there are only three days. During the past 10 springs, only 2007, 2010 and 2011 have had more then the normal three days with highs of 85 degrees or warmer.  This was the 10th April in a row Grand Rapids had warmed to at least 80 degrees.  The most persistent cold weather was the last week of March when high temperatures stayed below 35 degrees for four straight days.

Fig. 2. Same as Fig. 1, except for Lansing.

Lansing’s daily temperature data show very similar trends to Grand Rapids. For the most part, the warmer than normal days were as frequent as the colder than normal days. Curiously, Lansing averages only one day with highs of 85 degrees or warmer during the spring.   

 Fig. 3. Same as Fig. 1, except for Muskegon.

            Muskegon’s daily data reflected similar trends to both Grand Rapids and Lansing with the frequency of above and below normal days nearly the same. The warmth of April 10th stands out very clearly. The cold period the last week of March shows up clearly too.

 

  Fig. 4. The spring 2011 daily mean temperature and departure from normal for Michigan.
  

Fig. 5). Given that there are 117 years of data, 2011 is in the near normal category. 

The spring mean temperature across the area was 44.8°F, which was 0.4°F cooler than the 1971 to 2000 normal (Fig. 4). For the State of Michigan, it was the 51st coldest on record

 

Fig. 6. Spring mean area temperature departure from normal for the Southwest Lower Michigan long-term climate stations from 1950 through 2011.

The average temperature for the spring of 2011 was 44.8 degrees. That was 0.4 degrees cooler than normal (1971-2000). The spring of 2011 was signifcantly cooler than 2010 (4.9 degrees above normal). Of the past 10 springs in Southwest Lower Michigan, four springs were cooler than 2011:  2002 (43.3 degrees), 2003 (44.5 degrees), 2005 (44.4 degrees) and 2008 (44.4 degrees). This suggests a near normal status for the mean temperature for Southwest Michigan during the Spring of 2011. To be in the below normal class (bottom 1/3), the mean temperature would have had to be colder than 43.6 degrees. Of the past 10 spring seasons, only 2002 was colder than normal. 

Fig. 7. Temperature trend (mean temperature from 2002-2011 minus the mean temperature from 1971-2000), from March through May across the contiguous United States.


The temperature trend for Southwest Lower Michigan over the past 10 springs (2002-2011) shows very little trend (Fig. 7). Most of Southwest Lower Michigan was in the white area on the map, or in the -0.3 to +0.3 range. This matches what we see in Figure 6, which shows the number of warmer than normal years is about equal the number of below normal years.

 
Spring 2011 Precipitation for Southwest Lower Michigan:

Precipitation for Spring 2011 (Fig. 8a) ranged from 16.59 inches in Hastings (7.69 inches above normal) to 8.97 inches in Hart (1.03 inches above normal). Most locations in the central and southern area were 4 to 6 inches above normal (Fig. 8b). This was the 5th wettest spring on record for Southwest Lower Michigan.

Fig.8. Spring 2010 total precipitation (8a) .

Fig.8. Spring 2010 total precipitation  (8b).

              Of the last 10 springs, five were wetter than normal (including the spring of 2011), two were drier than normal, and three were near normal (Fig. 9). This is also shown well by the NCDC state rankings map (Fig. 10) which lists Michigan as the 116th wettest on record out of 117 years of data. The trend toward wetter springs shows up strongly in the Climate Prediction Center’s spring trend map (Fig. 11).  The excessive wetness over the Southeast Lower Michigan (Fig. 8a) is why Southwest Lower Michigan was the 5th wettest while the state as a whole was the 2nd wettest.

Fig.9. Spring precipitation average departure from normal for the 36 long-term climate stations over Southwest Lower Michigan from 1950 through 2011 

 

Fig.10. NCDC spring precipitation ranking for the contiguous United States

 

Fig. 11. Spring precipitation trend (percent of normal) over the past 15 years for the Contiguous United States (CONUS).

             At all three primary climate sites, overall rainfall was above normal (Figs. 13-15). Rainfall was above normal in every month too. April was the wettest month with many locations getting more the double what is normal for April. Note how on all three charts, the red line (normal) is below the accumulated precipitation through most of the spring.

Fig. 12. Grand Rapids daily precipitation accumulation for the spring of 2011.

Fig.13. As in Fig. 12 except for Lansing.

Fig.14.  As in Fig. 12 except for Muskegon.

 

Spring 2010 Severe Storms for Southwest Lower Michigan:


Fig.15. The total spring severe storm episodes for Southwest Lower Michigan. A severe weather episode is when there are at least three severe storm events within six hours in the Grand Rapids County Warning Area (CWA).

Severe storm frequency was well above normal for the spring of 2011, which in a La Nina spring is typical. There were five severe storm episodes (Fig. 15) over Southwest Lower Michigan. By contrast, both the springs of 2010 and 2009 had only one episode. The mean for the past 10 years is three and for the past 30 years the average is four episodes. The most active spring was 1991 with nine episodes. The biggest episode for the spring of 2011 was on the 29th of May with 36 severe reports. This is the second highest severe storm count for any day in May. The Derecho of May 31, 1998 had 37 severe storm reports. That remains in first place for the most active severe storm day in May for the Grand Rapids County Warning Area.

 

Spring 2011 Snowfall for Southwest Lower Michigan:

Snowfall totals ranged from around 10 inches over northern sections, to under 2 inches in areas near and south of Interstate 96 (Fig 16). Snowfall was once again well below normal during the spring of 2011 (Fig 17). The greatest reported snowfall during the spring of 2011 was the 10.4 inches at Big Rapids. The lowest reported snowfall total for the spring of 2011 was the 1.6 inches at Muskegon.

There were three significant snow events during the spring of 2011.   The first event was around the 9th of March when 2 to 5 inches fell along and near Route 10.   The biggest storm was from the 22nd into the 23rd when 6 to 12 inches fell north and east of a line from Lansing to Big Rapids. That last storm of the season was on the 19th of April when 1 to 2 inches fell north of Route 10

Fig. 16. Spring 2011 seasonal snowfall total for Michigan (all occurring on March 20th).


Fig. 17  Spring 2011 snowfall depature from normal.

 

For more details on the individual snow events and rainfall events, please see the monthly weather summaries listed below:

 

 March 2011 Climate Summary:http://www.crh.noaa.gov/images/grr/climate/CS201103.pdf

             April 2011 Climate Summary:http://www.crh.noaa.gov/images/grr/climate/CS201104.pdf

             May 2011 Climate Summary:http://www.crh.noaa.gov/images/grr/climate/CS2011005.pdf

 

 



Return to News Archive

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.