July 2013 Monthly Climate Summary

...JULY 2013 MONTHLY CLIMATE SUMMARY...

Across the Mid-South, July 2013 was cooler than normal, with some areas experiencing precipitation totals that also fell below normal. The month witnessed several weather patterns that brought cooler air, patterns that are more common in the spring months as opposed to the dead of summer. To put things into perspective, when compared to 2012, the average temperature in Memphis during July 2013 was 4.8 degrees behind the 85.3 degree average temperature during the same period last year. However, when considering the normal temperature for July for the Memphis area, 82.7 degrees, Memphis was only 2.2 degrees below normal. This shows the difference that a year can make; July 2012 was 2.6 degrees above normal, while July 2013 was 2.2 degrees below normal. The heat index is frequently referenced during the summer months, as it takes into account both the temperature and the dew point temperature. The average heat index at Memphis International Airport during July 2012 was 101 degrees, while the average heat index at the same location this July was only 93 degrees.

Considering other locations around the Mid-South, all sites saw below normal temperatures this July. Jackson was the most below normal, at 2.9 degrees below, while Jonesboro was the least below normal, at only 1.3 degrees below normal. Contributing to Jackson’s below normal temperature for July was the record low temperature for July 3^rd, which was previously 59 degrees back in 1959, but was 58 degrees this year. Memphis had the warmest average temperature at 80.5 degrees, while Jackson had the coolest. In fact, July 2013 was the third coolest on record for Jackson.

In addition to being the coolest site in the Mid-South this July, Jackson was also the wettest with 5.60 inches of precipitation. This was 1.11 inches above the July normal for Jackson, making Jackson the only site with an above normal precipitation total this month. Tupelo once again had the greatest below normal precipitation total with 0.96 inches below normal. Memphis was next with 0.86 inches below normal, and Jonesboro finished the month with only 0.15 inches of precipitation below normal. Additionally, Jackson and Jonesboro both broke daily maximum rainfall records this month. Jackson did so on July 21^st when 1.15 inches of rain fell, breaking the old record of 1.10 inches that was set on that date back in 1959. Jonesboro received 1.99 inches of rain on July 23^rd, breaking the previous record for that date, set all the way back in 1903.

TEMPERATURE DATA:

                              Memphis   Jackson   Jonesboro  Tupelo

Average Temperature (July)   :  80.5      76.6      79.5      79.6

Normal Avg. Temp (July)      :  82.7      79.5      80.8      81.4

Departure from Normal (MONTH):  -2.2      -2.9      -1.3      -1.8

Average Temperature (2013)   :  61.4      58.1      59.1      61.1

Normal Avg. Temp (YEAR)      :  62.5      59.4      59.5      62.0

Departure from Normal (YEAR) :  -1.1      -1.3      -0.4      -0.9

PRECIPITATION DATA:

                              Memphis   Jackson   Jonesboro  Tupelo

Total Precipitation (July)   :  3.73      5.60      3.39      2.94

Normal Precipitation (July)  :  4.59      4.49      3.54      3.90

Departure from Normal (MONTH): -0.86      1.11     -0.15    -0.96

Total Precipitation (2013)   : 43.78     43.36     33.73    33.41

Normal Precipitation (YEAR)  : 32.50     32.87     28.57    33.02

Departure from Normal (YEAR) : 11.28     10.49      5.16      0.39

2013 Midway Climate Review:

With seven months of 2013 behind us, and only five more remaining, a look back at the climate this year so far seems appropriate. So far for the year, all four sites around the Mid-South have average temperatures that are below normal. Jackson leads as the “coolest” site in the region at 1.3 degrees below normal for 2013, with Memphis close behind at 1.1 degrees below normal. Tupelo and Jonesboro are at 0.9 and 0.4 degrees below normal for 2013 so far, respectively. Logically this makes sense, being that only two out of the past seven months witnessed temperatures above normal. Those months were January and June. February, March, April, May, and July all witnessed below normal temperatures. An exception to this would be Jonesboro in the month of February, as Jonesboro was slightly, 0.6 degrees, above normal this February.

Looking at these below normal temperatures even closer, much of this could be contributed to the cooler than normal spring, March through May, witnessed around the area. In fact, when considering the average temperature for these three months, Jonesboro had its coolest spring on record at 55.4 degrees. Jackson tied for its second coolest spring on record at 56.5 degrees, while Memphis tied for its thirteenth coolest spring at 59.8 degrees. Tupelo tied for its seventh coolest spring on record with a March through May average temperature of 59.4 degrees.

While temperatures so far this year have been below normal, 2013 has been an above normal year in terms of precipitation. In fact, Memphis is currently 11.28 inches of precipitation above normal for the year so far. Jackson and Jonesboro also have above normal precipitation amounts for 2013 so far with 10.49 inches and 5.16 inches above normal, respectively. Tupelo is barely holding above normal currently, with just 0.39 inches of precipitation above normal for the year to date. Looking back over the past seven months, January, April, and May have been primarily above normal in precipitation amounts. Exceptions include Jonesboro being above normal in February, as well as Jonesboro being below normal in April. Other than that, all sites saw above normal precipitation for those three months. May has been the wettest month so far this year with a combined 35.64 inches of precipitation among the four sites.

Whether we will remain on this below normal temperature and above normal precipitation trend remains unknown. Predicting the rest of 2013 is a challenge at this point, with the Climate Prediction Center (CPC) giving equal chance for both temperature and precipitation for all months in the remainder of 2013. This means that August through December could be either above or below normal in both temperature and precipitation. There is simply no clear indication in either direction at this time.

MAYE