As of August 27th, Pierre has yet to record record a high temperature of 100F this summer.  The warmest temperature recorded at Pierre this summer has been 97F -- most recently on August 12th.  

A summary of the temperature trends this year indicate that the number of calendar days when the high temperatures have exceeded 90F, 95F or 100F at Pierre, Aberdeen, and Watertown are still well below climatological averages (see listings below) and very much mimic the trends from the cool summer of 2008.  Recall that last summer Pierre failed to reach 100F for only the second time since 1933.  In addition, Pierre has never experienced back to back summers when temperatures have failed to reach 100F.    

Temperatures through the end of August are forecast to remain at or below normal.  Warmer temperatures are expected by the middle part of next week (1st week in September) however at this point, 100F temperatures appear unlikely.  Pierre has experienced 100F temperatures all the way through September 26th -- so 100F temperatures remain a possibility for at least another month or so.  However, based on the current trend of below normal temperatures, this does not appear likely.      

Listed below are the dates when the temperatures last reached 100F at selected cities in the NWS Aberdeen Forecast area:

• Aberdeen (102F):  July 7, 2007 
• Pierre (101F): - September 4, 2007
• Watertown (100F): July 7, 2007  
• Mobridge (100F): - August 13, 2007
• Wheaton (100F): - July 8, 2007  

ABERDEEN (1893-2008) - AVG NUMBER OF DAYS IS BASED ON 30 YEAR NORMALS (1971-2000) 

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 100F: 2.3

2009....0

2008....0

2007....1
2006....5
2005....0
2004....0

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 95F:  7.7
2009....1

2008....0
2007....4
2006....10
2005....3
2004....0

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 90F: 20.5

2009....6

2008....10
2007....13
2006....17
2005....14
2004....2

RECORD HOTTEST TEMPERATURE:              115 F (7/9/1936)

                                               (7/6/1936)
YEAR WITH THE MOST 100F TEMPERATURES:    1936 - 35 DAYS 
YEAR WITH THE MOST 95F TEMPERATURES:     1936 - 44 DAYS 
YEAR WITH THE MOST 90F TEMPERATURES:     1936 - 69 DAYS 
EARLIEST 90F TEMPERATURE:                4/4/1921
LATEST 90F TEMPERATURE:                  10/16/1991
EARLIEST 100F TEMPERATURE:               5/1/1959
LATEST 100F TEMPERATURE:                 9/22/1936

PIERRE (1933-2008)  - AVG NUMBER OF DAYS IS BASED ON 30 YEAR NORMALS (1971-2000) 

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 100F:  8.8

2009.....0

2008.....0
2007.....10
2006.....14
2005.....14
2004.....4

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 95F:  21.6
2009.....7

2008.....5
2007.....20
2006.....37
2005.....32
2004.....16

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 90F: 42.7
2009.... 21

2008.....19
2007.....44
2006.....60
2005.....53
2004.....32

RECORD HOTTEST TEMPERATURE:               117 F (7/15/2006)
YEAR WITH THE MOST 100F TEMPERATURES:     1936 - 41 DAYS
YEAR WITH THE MOST 95F TEMPERATURES:      1936 - 58 DAYS
YEAR WITH THE MOST 90F TEMPERATURES:      1936 - 79 DAYS
EARLIEST 90F TEMPERATURE:                 4/9/1976
LATEST 90F TEMPERATURE:                   10/29/1933
EARLIEST 100F TEMPERATURE:                5/8/1934
LATEST 100F TEMPERATURE:                  9/26/1974

WATERTOWN (1893-2008)  - AVG NUMBER OF DAYS IS BASED ON 30 YEAR NORMALS (1971-2000) 

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 100F:  0.8

2009.....0

2008.....0
2007.....1
2006.....4
2005.....0
2004.....0

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 95F:  4.9
2009.....0

2008.....0
2007.....3
2006.....7
2005.....4
2004.....0

AVG NUMBER OF DAYS WITH TEMPERATURES AT OR ABOVE 90F: 14.9
2009.....3

2008.....4
2007.....13
2006.....17
2005.....14
2004.....2

RECORD HOTTEST TEMPERATURE:                110 F (7/20/1934)
YEAR WITH THE MOST 100F TEMPERATURES:      1933 - 17 DAYS
YEAR WITH THE MOST 95F TEMPERATURES:       1936, 1933 - 34 DAYS
YEAR WITH THE MOST 90F TEMPERATURES:       1933 - 53 DAYS
EARLIEST 90F TEMPERATURE:                  4/2/1910
LATEST 90F TEMPERATURE:                    10/5/1963
EARLIEST 100F TEMPERATURE:                 5/28/1934
LATEST 100F TEMPERATURE:                   9/10/1931

 Mike Fowle - Science and Operations Officer