September 2014 Climate Summary

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

Temperature Summary

September temperatures were largely near normal across the High Plains Region. While most average temperatures were within 2.0 degrees F (1.1 degrees C) of normal, there were a few warmer spots. A large area of western Colorado and a few pockets of southern Wyoming had temperature departures of 3.0-4.0 degrees F (1.7-2.2 degrees C) above normal. Alamosa, Colorado, located in the south-central part of the state, had its second warmest September on record with an average temperature of 58.7 degrees F (14.8 degrees C). The warmest September occurred with a temperature of 59.0 degrees F (15.0 degrees C) back in 1933 (period of record 1906-2014).

Record yields are expected for both corn and soybean crops even though development was behind due to a cool, wet summer. Because of the conditions this summer, combined with late planting there is a higher risk for frost/freeze damage in the northern part of the High Plains Region. Freezing temperatures did impact late season crop development in some areas, however the overall impact has not been serious. Warmer temperatures prevailed at the last week of the month with departures ranging from 6.0-12.0 degrees F (3.3-6.7 degrees C) above normal for a large area extending from Kansas north through the Dakotas. These warm temperatures offered good harvest weather, aided row crop development in some parts, and helped with crop dry down in others.

Precipitation Summary

There were areas of extreme wetness and dryness this month across the High Plains Region. A large area of southern North Dakota, central and eastern South Dakota, and isolated pockets throughout the Region received at best 50 percent of normal precipitation. Wichita, Kansas was one dry location and only received 0.47 inches (12 mm), or 15 percent of normal precipitation. This ranked as the 6th driest September on record in Wichita. The driest September occurred back in 1956 with 0.03 inches (1 mm) (period of record 1888-2014).

Areas receiving over 150 percent of normal precipitation included western Wyoming, central Kansas, parts of eastern Nebraska, and a large swath running from southwestern to northeastern Colorado up through eastern Wyoming, the panhandle of Nebraska, and western South Dakota. It was the wettest September on record in areas of the Black Hills with widespread precipitation totals of at least 200 percent of normal and isolated locations topping 300 percent of normal. Rapid City, South Dakota had its second wettest September on record with 3.17 inches (81 mm). This amount was 1.88 inches (48 mm) above normal, or 246 percent of normal precipitation. The record of 3.94 inches (100 mm) set back in 1946 held (period of record 1942-2014). An early season snowstorm brought the earliest recorded snow to the Black Hills this month. 1.6 inches (4 cm) fell at the Rapid City National Weather Service Office, while 8.1 inches (21 cm) fell at Mount Rushmore. That made this September the second snowiest for Mount Rushmore coming in just shy of the record of 8.3 inches (21 cm) set back in 1965 (period of record 1962-2014).

Another wet location was Lincoln, Nebraska which had its 7th wettest September on record (period of record 1887-2014). A late month heavy rain event dropped 5.0-8.0 inches (127-203 mm) across the city during the day of the 30th and during the early morning hours of October 1. The September total for the Lincoln Municipal Airport was 6.89 inches (175 mm) (this total does not include the precipitation which fell on October 1). Flooding was an issue for roads, lakes, streams, and basements. According to the Omaha/Valley National Weather Service Office, this was a 1 in 200 year event.  The past three months have all ranked in the top 10 for Lincoln with the city having its 7th driest July, 6th wettest August, and 7th wettest September.

The heavy precipitation across the Region has led to much above normal to high flows in the Missouri River Basin. Long-term conditions have also impacted flow in the Basin. For instance, the Black Hills of South Dakota has been experiencing higher flows since the October 2013 blizzard, while lower flows were present along the Republican River, which has been experiencing long-term drought effects. Additionally, increased soil moisture conditions were present across much of Wyoming, the western Dakotas, the panhandle of Nebraska, western and northern Colorado, and eastern Nebraska. Meanwhile, eastern Kansas showed drier conditions.

Climate Outlook

Like last month, ENSO-neutral conditions continued, but there is still a 60-65 percent chance of El Niño development during the fall and winter. The temperature outlook through December indicates a higher probability of above normal temperatures for much of the United States and includes northern portions of the High Plains Region - the Dakotas, northeastern Nebraska, and northern and western Wyoming. No areas in the Region have a higher probability for below normal temperatures. Meanwhile, the precipitation outlook shows a higher probability for above normal precipitation in southern Colorado and southwestern Kansas. All other areas in the Region have equal chances of above, near, or below normal temperatures and precipitation.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

More improvements were in store this month as heavy rains impacted the High Plains Region. The total area in drought (D1-D4) dropped from 21 percent to 12 percent. Nebraska and Wyoming joined the Dakotas as the drought free states in the Region. At the end of the month, all drought was confined to Colorado and Kansas, however there were improvements in both states. Over the past month, Kansas went from 88 percent in drought to 46 percent in drought. The extreme drought conditions (D3) in the northwestern part of the state improved one category and only 2 percent of the state was left with D3. Many improvements were made in northern and eastern areas of the state as well. In Colorado, the main improvement was the removal of moderate drought conditions (D1) in the northwestern portion of the state. Drought in the southeastern part of the state remained about the same, although there were some improvements in the southwest corner of the state. According to the U.S. Seasonal Drought Outlook released September 18th, all drought conditions in the Region should improve or be removed.