National Weather Service Weather Forecast Office

 

August of 2007 will be remembered for its extreme heat. The month was characterized by an extended period of days with temperatures in the 90s. This was in a sharp contrast to July, which had been a slightly below normal month. This August can be characterized as the hottest since 1983. In addition to the heat, rainfall remained very hard to come by in parts of central and southern Indiana. While soaking rains found their way into more northerly locations, some spots ended up with less than an inch of rain in August.

 

The average temperature of August 2007 at the Indianapolis International Airport was 79.9 degrees. This was above the normal August value of 73.5 degrees by 6.4 degrees. This made August 2007 the third warmest August ever in the Indianapolis area. It was the warmest August since 1983, when the average temperature in Indianapolis was 80.1 degrees. This year the temperature just narrowly missed making this the second warmest August ever, as a late month cool down pushed the average temperature for the month lower.  

 

 

 

 

 

 

 

 

 

The month can be best described as an extended period of hot weather. The only real break in the heat came on the last two days of the month, the only two days of the month that failed to reach at least 80. Slightly cooler weather was also noted on the 18^th, the only day besides the 31^st when the average temperature for the day was below normal.

 

The first 13 days of the month brought daily highs of 90 degrees or hotter each day. The last day of July had also been over 90 degrees, which made for a streak of 14 consecutive days of 90 or greater. This was the longest streak of its kind since 1983, and the 4^th longest of all time. The streak broke on August 14 when the high only hit 85 degrees. The second half of the month brought many more days of 90 degrees or hotter, but only for 2 or 3 days in a row at a time. The hottest temperature during the month at Indianapolis was 96 degrees, reached on August 12.

 

The month also entered the record books for its numbers of days of 90 degrees or hotter. An amazing 22 days this month brought a high in the 90s. A normal August would bring 5 days in the 90s, and in fact the normal total for an entire year is 18 days. The only time that more days in August were 90 degrees or higher was in 1983, when 23 days reached the mark.

 

While no record high temperatures fell this month, there was a record tied on August 9^th for the warmest night time low on the date. The low this August 9 only fell to 78 degrees, which tied the previous record on the date, set back in 1896. The average low temperature for the entire month was 69.9 degrees, and only one night saw temperatures fall below 60 degrees, which happened the morning of August 31.

 

Temperature data for selected sites in central Indiana during the month of August, 2007:

 

 

*Data from Lafayette on August 20 was missing due to equipment malfunction. Calculated values are based on an average of the other 30 days.

 

 

 

The monthly rainfall total at Indianapolis in August 2007 was 3.43 inches. This was below the normal value of 3.82 inches by 0.39 inches.

 

Rainfall in August 2007 at Indianapolis came almost exclusively in one day. August 20^th brought heavy downpours totaling 2.22 inches at the Indianapolis International Airport. This broke a record for the heaviest rain ever on that day, shattering the previous daily record of 1.63 inches set in 1924. This one day rainfall saved the Indianapolis area from what would have been one of the driest Augusts ever. This one day total was 65% of the total rainfall for the entire month.

 

August 2007 was the 5^th month in a row with below normal rainfall at Indianapolis. The departure from normal rain from April 1^st to August 31^st is 7.52 inches.

 

There were two extremely dry periods during the month. During the 7^th to 19^th of the month, only a Trace of rain fell. From the 21^st through the end of the month, only 0.11 inches of rain fell at Indianapolis. These two very dry periods were broken up by the excessive rains of the 20^th.

 

 

Rainfall totals for selected sites in central Indiana during the month of August, 2007:

 

 

*Data from Lafayette is missing August 20^th due to equipment malfunction. Actual monthly rainfall total may be higher than indicated but a total for the other 30 days was used.

** Data from Muncie is missing August 25^th due to equipment malfunction. Actual monthly rainfall total may be higher than indicated but a total for the other 30 days was used.

 

The official temperature and precipitation outlooks for the month of September show an equal chance of above, below, or near normal values in Indiana.

 

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Data Prepared by Logan Johnson, Climate Services Focal Point

Assistance was provided by the National Weather Service Forecast Team