The U.S. Winter Outlook – What A 3rd Consecutive La Niña Means For You

I recently wrote an article cautioning you about all of the hoax and hyped snowstorm posts you will likely see this winter. This piece focuses on what the actual experts say about the upcoming winter season. When I say experts, I mean the National Oceanic and Atmospheric Administration (NOAA) not rodents or almanacs. The agency issued its U.S. winter weather outlook this week and warned about a “triple-dip” La Niña. Here are the key things to know about it, and what it could mean for your winter weather.

The first thing that caught my eye is that the agency is calling for a third consecutive season of La Niña. NOAA’s Climate Prediction Center says there is a 75% chance of La Niña conditions during the winter. The NOAA website reminds us that La Niña represents, “Below-average sea surface temperatures (SSTs)….across the central and eastern equatorial Pacific Ocean.” Like the warmer “brother” scenario El Niño, these conditions impact weather around the globe through teleconnection patterns. In other words, water temperatures in the equatorial Pacific can change atmospheric patterns everywhere (see graphic below).

According to the recently issued press release, “NOAA predicts drier-than-average conditions across the South with wetter-than-average conditions for areas of the Ohio Valley, Great Lakes, northern Rockies and Pacific Northwest.” These patterns are very typical of the La Niña pattern. Unfortunately, this pattern likely means continued drought conditions in parts of the Western U.S. and souther Great Plains. Drought is currently impacting roughly 60% of the U.S. Jon Gottschalck is Chief of the Operational Prediction Branch at NOAA’s Climate Prediction Center. He said, “With the La Niña climate pattern still in place, drought conditions may also expand to the Gulf Coast.”

As the NASA Earth Observatory website notes, “Part of the El Niño-Southern Oscillation cycle, La Niña appears when energized easterly trade winds intensify the upwelling of cooler water from the depths of the eastern tropical Pacific, causing a large-scale cooling of the eastern and central Pacific ocean surface near the Equator.” Changes in atmospheric wind patterns and moisture are the stimulus for those global teleconnections. This third consecutive season of such conditions so scientists and the media have called it a triple-dip La Niña. World Meteorological Organization (WMO) Secretary-General Prof. Petteri Taalas said, “It is exceptional to have three consecutive years with a La Niña event.” He also warned that devastating drought in African and South America will persist because of it.

La Niña and El Niño are a part of our naturally-varying climate system, but as the WMO press release cautions, “….All naturally occurring climate events now take place in the context of human-induced climate change, which is increasing global temperatures, exacerbating extreme weather and climate, and impacting seasonal rainfall and temperature patterns.”

According to NOAA, the agency updates the seasonal outlooks each month. Their press release says, “The next update will be available November 17.”