The following table summarizes the longest streaks of having the air temperature at or above 70 degrees in September. This table is based on the IEM archives of hourly temperature reports from the ASOS stations in the state. Note: For Burlington, the current streak is ongoing, but likely to end this evening without eclipsing the largest value.

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 Data Since: 1949 Station: [ALO] Waterloo
  1. 01 Sep 1960 12:00 AM -> 05 Sep 1960 06:00 AM    102 hours
  2. 04 Sep 2015 07:54 AM -> 08 Sep 2015 06:54 AM     95 hours
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 Data Since: 1996 Station: [AMW] Ames
  1. 04 Sep 2015 08:53 AM -> 08 Sep 2015 06:27 AM     94 hours
  2. 01 Sep 2011 12:53 AM -> 03 Sep 2011 12:53 AM     48 hours
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 Data Since: 1948 Station: [BRL] BURLINGTON
  1. 01 Sep 1985 12:00 AM -> 09 Sep 1985 07:00 AM    199 hours
  2. 02 Sep 2015 06:53 AM -> 08 Sep 2015 11:53 AM    149 hours (ongoing)
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 Data Since: 1972 Station: [CID] CEDAR RAPIDS
  1. 03 Sep 1990 11:00 AM -> 07 Sep 1990 11:00 PM    108 hours
  2. 04 Sep 2015 07:52 AM -> 08 Sep 2015 08:52 AM     97 hours
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 Data Since: 1951 Station: [DBQ] DUBUQUE
  1. 01 Sep 1960 07:00 AM -> 05 Sep 1960 07:00 AM     96 hours
  7. 04 Sep 2015 07:32 AM -> 07 Sep 2015 03:53 AM     68 hours
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 Data Since: 1928 Station: [DSM] DES MOINES
  1. 01 Sep 2015 07:54 AM -> 08 Sep 2015 08:54 AM    169 hours
  2. 06 Sep 2013 07:54 AM -> 12 Sep 2013 03:54 AM    140 hours
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 Data Since: 1996 Station: [DVN] QUAD CITIES
  1. 07 Sep 2013 07:52 AM -> 11 Sep 2013 10:52 PM    111 hours
  2. 04 Sep 2015 07:52 AM -> 08 Sep 2015 10:52 AM     99 hours
  5. 01 Sep 2015 12:52 AM -> 04 Sep 2015 03:52 AM     75 hours
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 Data Since: 1987 Station: [EST] ESTHERVILLE
  1. 07 Sep 1987 01:00 PM -> 10 Sep 1987 06:00 PM     77 hours
  2. 04 Sep 2015 08:52 AM -> 07 Sep 2015 01:52 AM     65 hours
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 Data Since: 1996 Station: [IOW] IOWA CITY
  1. 03 Sep 2015 07:52 AM -> 08 Sep 2015 10:52 AM    123 hours
  2. 07 Sep 2013 07:52 AM -> 12 Sep 2013 12:52 AM    113 hours
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 Data Since: 1973 Station: [LWD] LAMONI
  1. 01 Sep 1976 05:00 PM -> 09 Sep 1976 07:00 PM    194 hours
  2. 01 Sep 2015 12:53 AM -> 08 Sep 2015 07:18 AM    174 hours
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 Data Since: 1948 Station: [MCW] MASON CITY
  1. 01 Sep 1973 12:00 AM -> 03 Sep 1973 09:00 PM     69 hours
  -- 2015 not in top 10 for site --
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 Data Since: 1996 Station: [MIW] MARSHALLTOWN
  1. 06 Sep 2013 08:53 AM -> 09 Sep 2013 02:53 AM     66 hours
  4. 01 Sep 2015 07:53 AM -> 03 Sep 2015 05:53 AM     46 hours
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 Data Since: 1947 Station: [OTM] OTTUMWA
  1. 07 Sep 1978 09:00 AM -> 13 Sep 1978 04:00 AM    139 hours
  -- 2015 not in top 10 for site --
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 Data Since: 1996 Station: [SPW] SPENCER
  1. 03 Sep 2015 07:53 AM -> 07 Sep 2015 02:32 AM     91 hours
  2. 11 Sep 2005 07:53 AM -> 13 Sep 2005 12:53 PM     53 hours
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 Data Since: 1948 Station: [SUX] SIOUX CITY
  1. 01 Sep 1990 12:00 AM -> 05 Sep 1990 07:00 AM    103 hours
  3. 03 Sep 2015 07:52 AM -> 07 Sep 2015 01:52 AM     90 hours