August 2010 Climate Summary

For a printable version of the climate summary which includes more figures, data tables, and state summaries, click here. 

Temperature Summary

August 2010 was warmer than normal for much of the High Plains Region.  Meanwhile, precipitation varied across the Region.  In the wet areas, the warm temperatures were welcome as this aided in crop development and the harvest of small grains.  However, in areas which have been dry, the warm temperatures stressed some row crops and livestock.  Temperature departures across the eastern half of the Region ranged from 2-4 degrees F (1.1-2.2 degrees C) above normal and isolated areas of Colorado, Kansas, Nebraska, and South Dakota were 4-6 degrees F (2.2-3.3 degrees C) above normal.  The warmer than normal temperatures were not hot enough to break records, although a few locations in Colorado and Kansas were able to break into the top 10 warmest Augusts on record.  This month’s warm spot was Alamosa, Colorado which is located in the south central portion of the state.  Alamosa had its 9th warmest August on record (period of record 1906-2010) with an average temperature of 64.4 degrees F (18.0 degrees C).  

Overall, the summer (June, July, and August) was also warmer than normal for many locations in the Region, especially Colorado and Kansas where temperature departures were 2-4 degrees F (1.1-2.2 degrees C) above normal.  Alamosa, Colorado recorded its warmest summer on record with an average temperature of 64.4 degrees F (18.0 degrees C).  The previous warmest summer on record was set in 2007 with an average temperature of 64.1 degrees F (17.8 degrees C).  Wichita, Kansas recorded its 5th warmest summer on record (period of record 1888-2010) with an average temperature of 82.3 degrees F (27.9 degrees C).  The warmest summer on record in Wichita occurred in both 1936 and 1934 with an average temperature of 85.3 degrees F (29.6 degrees C). 

Precipitation Summary

Precipitation was spotty across the High Plains Region this month.  Some areas of the Region, including central South Dakota, northern Nebraska, eastern and west central Kansas, and central and eastern Wyoming, received precipitation which was only 50 percent of normal or less.  Meanwhile, other areas including southeastern South Dakota, eastern Colorado into southwestern Nebraska, and central Kansas received greater than 150 percent of normal precipitation.  These precipitation totals were not enough to break records in August, however new precipitation records were set for the summer (see table on page 2 of the August 2010 Climate Summary).  

This month’s wet spot was Wessington Springs, South Dakota.  Wessington Springs received 3.95 inches (100.33 mm) of precipitation, or 178 percent of normal, which was the 9th wettest August on record (period of record 1893-2010).  For the summer, Wessington Springs received a total of 25.16 inches (639.07 mm) of precipitation which smashed the old record of 15.52 inches (394.21 mm) received in 1962.  Interestingly, the heavy precipitation this year now totals 35.43 inches (899.92 mm) which sets a new record for the entire year!  The previous record was 34.13 inches (866.90 mm) of precipitation received in 1995.  

The high precipitation led to flooding along rivers for much of the summer.  According to the National Weather Service in Valley, NE, the Missouri River at Brownville was above flood stage for 78 consecutive days from June 11th to August 28th.  The river crested at 42.89 feet, or 10.89 feet above flood stage, on June 22nd and this was the second highest crest ever reported at Brownville.  The highest crest occurred July 24, 1993 with a stage of 44.30 feet.

Climate Outlook

La Niña conditions were present across the equatorial Pacific this month and are likely to continue through early 2011.  The temperature outlook indicates a higher probability of above normal temperatures for Colorado, Kansas, the majority of Nebraska, the eastern halves of the Dakotas, and the far southeastern corner of Wyoming.  Equal chances of above, near, or below normal temperatures are predicted elsewhere.  The precipitation outlook indicates a higher probability of above normal precipitation for the majority of Nebraska and South Dakota, southern North Dakota, northwestern Kansas, and extreme northeastern Colorado.  Western Colorado has a higher probability of below normal precipitation.  Equal chances of above, near, or below normal precipitation are predicted elsewhere in the Region.  The seasonal outlooks combine the effects of long-term trends, soil moisture, and when applicable, the El Niño Southern Oscillation cycle (ENSO).  More information about these forecasts can be found here.

Drought Watch

While overall, summer 2010 was wet for many locations across the High Plains Region, some locations were drier than normal which led to significant changes in the U.S. Drought Monitor this month.  Early in the month, pockets of abnormally dry conditions (D0) were introduced to north central South Dakota, southeastern Nebraska, and northern Kansas.  Later in the month, moderate drought conditions (D2) developed in north central South Dakota as little rain fell and D0 conditions were also expanded into North Dakota.  Meanwhile, drought conditions remain unchanged in Wyoming and the D0 area in Colorado was trimmed slightly.  According to the U.S. Seasonal Drought Outlook released August 19th, the drought conditions in western Wyoming were expected to persist through November 2010.