September 2008 Climate Summary

September 2008 Indianapolis Climate Summary
Very Warm and Dry…
The weather this past September across Central Indiana continued the trends begun in August. This made a second month of dry weather…coupled with mild temperatures. The month was marked by a big weather story with the passage of Tropical Remnants, and significant in that no low temperatures in the 40s occurred, the first time since 1933 this has happened. The following is a summary of everything that was weather in September 2008 in Central Indiana.
The temperature this September was well above normal.  Only five days this month saw average temperatures that were below normal, compared to fifteen that saw average temperatures above normal. A remarkable feat was recorded, in that the lowest temperature for the entire month of September was 51 degrees. September is typically the first month to experience lows in the 40s in Indianapolis, and sometimes even 30s. The last time that September lows did not dip into the 40s was way back in 1933. The only other times it occurred before then were in 1910 and 1925.
The month kicked off with hot temperatures, well above normal for the first 3 days. The first three days of the month were in the 90s, including a high of 93 degrees on the 2nd that was the warmest temperature of the month. The weather then shifted to near or slightly below normal temperatures in what was a prolonged stretch of very pleasant weather that lasted through the 13th. There was a very warm day on the 13th with a high of 89. This was followed by more pleasant weather in the mid section of the month, before an extended period of above normal weather closed out the month. An average September experiences 2 days of 90 or better. This year there were three, which brings the annual tally to six, compared to a normal of 18. September’s days in the 90s equaled all the days in the 90s of the entire summer season.
The month finished with an average temperature of 70.1 degrees, which was above normal by 3.8 degrees, making it the 25th warmest September ever. Just last year, September was 7th warmest ever with an average temperature of 71.7 degrees. The coolest temperature this month came on the 10th with a low of 51 degrees, and the hottest high temperature was 93 degrees on the 2nd. This value is the hottest temperature of 2008.
No temperature records were set this month in the Indianapolis area.
The dry trend that began in August continued during September. The first two weeks of the month saw occasional light rain, with measurable precipitation happening on ten of the first fourteen days. The heaviest rain came on the 12th with 0.91 inches falling.  After this, the rain shut off on the 15th and only 0.16 fell during the final 15 days of the month.
There was a very long stretch of days with no measurable rain at all. From the 15th through the 28th, no measurable rain came, a string of 14 days. This is the 9th longest stretch ever without measurable rainfall during September.
The monthly total of September 2008 was 2.04 inches. This is below normal by 0.84 inches. This made it the second consecutive month this year with below normal rainfall.
For the year to date, 39.50 inches of rain has already fallen at Indianapolis International Airport. This compares to a normal through the end of September of 31.55 inches. Last year, there had only been 26.50 inches of rain through this point of the year.
Severe Weather
Severe weather was not a very common occurrence in Central Indiana this September, but this is common for the time of year. September is typically a dry and quiet month.
There was a severe weather event on the 20th of this month, with a few reports of hail to nickel size, and winds to nearly 70 mph with some tree damage.
The most significant weather event of the month was certainly the passage of the tropical remnants of Hurricane Ike, on the 14th of September. A wind gust of 63 mph was measured at the Indianapolis International Airport that day. Winds gusted as high as 80 mph across southern and central Indiana that afternoon. Widespread and significant damage was reported in many counties. Numerous trees and power lines were downed by the strong and gusty winds. Cleanup still continues in the hardest hit areas of southern Indiana.

There was thunder on five days at the Indianapolis Int’l Airport this month. Fog was reported on 16 days, with dense fog happening on the final day of the month. Sunshine for the month was 60% of possible.
Outlook for October 2008
The outlook from the Climate Prediction Center indicates equal likelihood of below, near, or above normal temperatures and precipitation in Central Indiana during October 2008.

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