National Weather Service United States Department of Commerce

NOAA's CPC Winter 2023-24 Outlook
for the Upper Mississippi River Valley

Released: Thursday, November 16, 2023


Bottom Line for the Local Area...

NOAA's Climate Prediction Center (CPC) forecast for the upcoming winter months of December-February:

  • Temperatures: Warmer than normal is favored across the Upper Mississippi River Valley.
  • Precipitation: Equal chances of drier, near, and wetter than normal. 

While a strong  (≥ 1.5°C for the seasonal average in Niño-3.4) El Niño is expected to impact the weather across much of the United States, its impacts in the Upper Mississippi River Valley can still be highly variable with both temperatures and precipitation. For more details on why these shifts were made, please see the local winter outlook tab below.



El Niño is anticipated to continue through the Northern Hemisphere spring (with a 62% chance during April-June 2024).

Above-average sea surface temperatures (SST) across the equatorial Pacific Ocean [Fig. 1] were indicative of a strong El Niño, with anomalies increasing in the central and east-central Pacific in the past month. The latest weekly Niño index values were +1.4°C in Niño-4, +1.8°C in Niño-3.4, +2.1°C in Niño-3, and +2.2°C in Niño-1+2 [Fig. 2]. Area-averaged subsurface temperature anomalies increased slightly [Fig. 3] associated with the initiation of a downwelling oceanic Kelvin wave, which strengthened above-average subsurface temperatures in the central equatorial Pacific [Fig. 4]. Low-level wind anomalies were westerly in the east-central Pacific, while upper-level wind anomalies were easterly in the western and central Pacific. Convection/rainfall was enhanced around the International Date Line, extending into the eastern Pacific. Suppressed convection/rainfall strengthened around Indonesia [Fig. 5]. The equatorial Southern Oscillation Index (SOI) and the station-based SOI remained negative. Collectively, the coupled ocean-atmosphere system reflected a growing El Niño.

The most recent IRI plume favors El Niño to continue through the Northern Hemisphere spring 2024 [Fig. 6]. Based on the latest forecasts, there is a greater than 55% chance of at least a "strong" El Niño (≥ 1.5°C in Niño-3.4 for a seasonal average) persisting through January-March 2024. There is a 35% chance of this event becoming "historically strong" (≥ 2.0°C) for the November-January season. Stronger El Niño events increase the likelihood of El Niño-related climate anomalies but do not necessarily equate to strong impacts (see CPC seasonal outlooks for probabilities of temperature and precipitation). In summary, El Niño is anticipated to continue through the Northern Hemisphere spring (with a 62% chance during April-June 2024; [Fig. 7]).

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA's National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center website (El Niño/La Niña Current Conditions and Expert Discussions). Additional perspectives and analyses are also available in an ENSO blog. A probabilistic strength forecast is available here. The next ENSO Diagnostics Discussion is scheduled for 14 December 2023.

This will be the first El Niño since 2018-19. That one was weak (0.5 - 0.9°C for the seasonal average in Niño-3.4). The last strong El Niño (≥ 1.5°C for the seasonal average in Niño-3.4) was 2015-16.

Besides El Niño, this winter will also be affected by:

  • Arctic Oscillation (AO) and North Atlantic Oscillation (NAO) - These oscillations can influence the number of Arctic air masses that penetrate into the Southern United States and nor'easters on the East Coast.
  • Eastern Pacific Oscillation (EPO) - This can affect the location of where the cold air masses will be located in the northern United States.
  • Madden-Julian Oscillation (MJO) - This can affect both temperatures and precipitation in the weekly time scale.