Contacts: Doug Kluck (doug.kluck@noaa.gov)

	 Natalie Umphlett (numphlett2@unl.edu)

Missouri Basin Region El Niño Impacts and Outlook | February 2016 Update

www.drought.gov/drought/regional-programs/mrb/missouri-river-basin-home

August 2015 Report: www.drought.gov/media/pgfiles/ENSO-MOBasin-2015-Final.pdf

El Niño Impacts 

and Outlook

Missouri Basin Region 

February 2016

Winter 2015/16 El Niño Update

El Niño Evolution

El Niño Outlook

The image above shows the typical 

pattern in the winter during El Niño events. 

Although each El Niño is not the same, 

there are some general patterns that are 

predictable. For instance, the polar jet stream 

is typically farther north than usual, while 

the Pacific jet stream remains to the south. 

This pattern brings above-normal 

temperatures to much of the Missouri 

Basin region, particularly in the north. Keep 

in mind that this does not mean that cold 

weather will not occur. Extreme cold weather 

may be milder and less frequent, however.

El Niño conditions were officially declared 

in Spring 2015. Conditions strengthened as 

predicted through November 2015, when the 

sea-surface temperature anomalies peaked 

at around 2.3°C on the Oceanic Niño Index 

(ONI). The peak makes this El Niño one of 

the strongest on record, tied with the El 

Niño of 1997/98. The bar chart below shows 

the likelihood of El Niño, La Niña, or neutral 

conditions over the upcoming seasons. The 

odds are highest for El Niño (red bars) through 

late spring, when the highest odds shift toward 

neutral (green bars) or La Niña (blue bars) 

through the summer and into the fall. This 

is a typical evolution of the ENSO pattern. 

El Niño Winter Pattern Winter 2015/16 To Date

A combination of factors led to a warm start to the winter, with El Niño and the Arctic Oscillation 

(AO) both contributing to these conditions. As we see to the left, we would expect this from a 

typical El Niño winter, but a positive phase to the AO was also present and this signals above-normal 

temperatures for areas east of the Rockies as well. These unseasonably warm temperatures had 

interesting impacts, such as green lawns and heavy rain, instead of snow. Because what normally 

falls as snow actually fell as rain, this allowed for higher precipitation totals than would be expected 

for this time of the year - the driest season for the Plains areas of the region. January was quite 

different from December, however, with much of the region having below-normal temperatures, 

with the main exception of North Dakota. Meanwhile, precipitation totals showed that the region 

was generally on the dry side, with only a few above-normal pockets. Mountain snowpack this 

season has generally been near normal in Colorado and below normal in parts of Montana and 

Wyoming, with some local variation within each state. This snowfall pattern is in line with earlier 

outlooks for the winter. Luckily, there are still chances for the snowpack to build through the spring.

Image courtesy of NOAA

www.climate.gov/news-features/department/enso-blog

The letters along the bottom are abbreviations for threemonth periods, from December-January-February (DJF) 

through August-September-October (ASO).

Temperature and Precipitation Outlooks 

The late winter/early spring outlook for the Missouri Basin is typical for an El Niño event with 

increased chances of above-normal temperatures from Montana and Wyoming east across the 

northern Plains and down through Nebraska, Iowa, and northern Missouri. The rest of the basin 

has equal chances for above-, below-, or near-normal temperatures. The precipitation outlook 

shows increased chances of above-normal precipitation across much of the central Plains and 

Rocky Mountains, with below-normal chances of precipitation confined to the upper reaches 

of the Missouri River in Montana. Season-to-date snowpack for the upper Missouri River and 

tributaries has been below normal, but areas of the central and southern Rockies have been above 

normal. This could have implications for many sectors, in both positive ways (increased snowpack 

to the south could be welcomed by ski resorts) and negative ways (reduced snowpack to the 

north could impact spring runoff). Although the peak of the event was reached in the equatorial 

Pacific (November), impacts in the Missouri Basin are typically realized in winter and early spring. 

The seasonal outlooks above combine many factors including dynamical models, the 

effects of long-term trends, soil moisture, and the El Niño Southern Oscillation cycle 

(ENSO). To learn more, or to retrieve the latest temperature, precipitation, and drought 

outlooks, please visit the Climate Prediction Center at: http://www.cpc.ncep.noaa.gov.

Precipitation Temperature

Outlooks valid for 

February - April 2016

EC: Equal chances of 

above, near, or below 

normal

A: Above normal 

B: Below normal

Percentages represent the 

probability for above-normal, 

below-normal, or equal chances.

Percent of Normal Precipitation (%)

December 1, 2015 - January 31, 2016

Departure from Normal Temperature (°F)

December 1, 2015 - January 31, 2016

Maps courtesy of the High Plains Regional Climate Center