Prognostic Discussion for Long-Lead Seasonal Outlooks 
NWS Climate Prediction Center College Park MD 
830 AM EDT Thu Aug 20 2026 
 
SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS 
 
El Niño conditions are present, as represented in current oceanic and 
atmospheric observations. El Niño is strengthening, with a greater than 90 
percent chance of a very strong event this fall and winter. 
 
The September-October-November (SON) 2026 Temperature Outlook favors above 
normal temperatures for most of Alaska as well as the western and central 
Contiguous United States (CONUS), the Great Lakes, Northeast, Mid-Atlantic, 
Florida, and coastal areas of the Southeast and Gulf. The highest probabilities 
(greater than 50 percent) of above normal temperatures are forecast across 
southeastern Alaska, the Pacific Northwest, Northern Rockies, and adjacent 
areas of the Northern High Plains and northwestern California. 
 
The SON 2026 Precipitation Outlook depicts enhanced probabilities of above 
normal precipitation amounts from the southwestern CONUS to the central and 
southern High Plains as well as for parts of the Southeast and western mainland 
Alaska. The greatest chances (higher than 40 percent) for above normal 
precipitation are indicated for much of the Southwest and adjacent areas of the 
Great Basin and Central and Southern Rockies as well as for parts of the 
coastal Southeast. A slight tilt toward below normal precipitation amounts are 
forecast across much of the Great Lakes, Northeast, and across northern and 
eastern Washington State and adjacent areas of northern Idaho and northwestern 
Montana. 
 
Equal chances (EC) are forecast for areas where probabilities for each category 
of seasonal mean temperatures and seasonal accumulated precipitation amounts 
are expected to be similar to climatological probabilities. 
 
BASIS AND SUMMARY OF THE CURRENT LONG-LEAD OUTLOOKS 
Note: For Graphical Displays of the Forecast Tools Discussed Below See: 
http://www.cpc.ncep.noaa.gov/products/predictions/90day/tools/briefing 
 
CURRENT ATMOSPHERIC AND OCEANIC CONDITIONS 
 
El Niño strengthened over the past month, with sea surface temperature (SST) 
anomalies exceeding +3.0°C in the eastern equatorial Pacific. The latest 
weekly Niño index values were +1.8°C in Niño-3.4, +2.5°C in Niño-3, and 
+3.2°C in Niño-1+2. The equatorial subsurface temperature index (average from 
180°-100°W) increased during July, reflecting a deeper-than-average 
thermocline. Subsurface temperature anomalies were significant, reaching 
+10.0°C at depth. Low-level westerly wind anomalies and upper-level easterly 
wind anomalies extended from the western to east-central equatorial Pacific. 
Convection and rainfall were enhanced from the central to eastern Pacific and 
were suppressed over Indonesia. The traditional and equatorial Southern 
Oscillation indices were significantly negative, with values near 2 standard 
deviations during July. Collectively, the coupled ocean-atmosphere system 
reflected a strengthening El Niño. 
 
PROGNOSTIC DISCUSSION OF SST FORECASTS 
 
The CPC Official El Niño Southern Oscillation (ENSO) Outlook, which 
synthesizes multiple models from North America and abroad, indicates El Niño 
will continue to strengthen through the end of the year. During the 
October-November-December (OND) 2026 season, there is a 69% chance of a 
historic event that would exceed the strength of previous El Niño events 
dating back to 1950 (+2.5°C or more for a 3-month RONI value). With an event 
of this magnitude, the chances of experiencing impacts consistent with El Niño 
are larger, but they are not guaranteed. In summary, El Niño is strengthening, 
with a greater than 90% chance of a very strong event during the Northern 
Hemisphere fall and winter 2026-27. 
 
PROGNOSTIC TOOLS USED FOR U.S. TEMPERATURE AND PRECIPITATION OUTLOOKS 
 
Composites derived from the current and forecast state of ENSO were strongly 
utilized due to the magnitude of this El Niño event. Additionally, analogs  
tuned to the current Eastern Pacific (EP) orientation of this El Niño event as 
well as its evolution from a preceding La Niña winter were consulted. 
Dynamical model forecasts from the North American Multi-Model Ensemble (NMME), 
the Climate Forecast System version 2 (CFSv2), and the Copernicus (C3S) 
multi-model ensemble system were also used for the first six leads when they 
are available, as was the objective, historical skill-weighted consolidation 
and Calibration, Bridging, and Merging (CBaM) guidance, that combines both 
dynamical and statistical forecast information. Analysis of antecedent 
conditions such as extratropical SST anomalies and sea ice extent were 
considered where appropriate. At later leads, decadal trends  in temperature and 
precipitation were increasingly relied upon in creating the seasonal outlooks. 
 
PROGNOSTIC DISCUSSION OF OUTLOOKS - SON 2026 TO SON 2027 
 
TEMPERATURE 
 
One of the major forecast challenges for the upcoming fall is balancing 
potential El Niño impacts with recent trends . Despite the magnitude of this El 
Niño, temperature impacts are surprisingly muted during the fall season, even 
among strong events, as the greatest impacts tend to express themselves during 
the winter months. Underscoring the lower fall predictability, the closest 
natural analogs  to the current El Niño event produced a wide variation of 
outcomes for SON, ranging from a cold eastern half of the CONUS to widespread 
warmth almost from coast to coast. At the same time, recent warm trends  
(comparing the last 15 years of observations to the 1991-2020 base climatology) 
for the SON season are among the strongest and most widespread of any three 
month period, especially across the western and central CONUS. As such, recent 
trends were relied upon extensively for the SON temperature outlook with El 
Niño becoming the dominant factor as we approach winter. Dynamical model 
guidance is generally in agreement with trends  in supporting increased chances 
of above normal temperatures across most of the country. A notable exception is 
the southern Plains, where recent trends  suggest a much greater chance of above 
normal temperatures than represented by model guidance. The temperature outlook 
for SON features an area of EC across the Ohio and Tennessee Valleys and 
adjacent areas, where warm trends  are relatively weak compared to other areas 
of the country. Elsewhere, the rest of the CONUS tilts warm, consistent with 
trends. The greatest confidence of above normal temperatures (above 50 percent 
chance) is forecast for the Pacific Northwest, Northern Rockies, and adjacent 
areas of northwestern California and the northern High Plains, where trends  and 
dynamical model guidance are in good alignment. Most of Alaska is also favored 
for above normal temperatures as trends , temperature counts of observations 
from strong to very strong El Niño events, and dynamical model guidance all 
support widespread warmth. Confidence is highest (greater than 50 percent 
chance) across southeastern parts of the state where the consensus of guidance 
yields the strongest warm signal. 
 
As we progress later in the Fall and especially through the winter (OND through 
February-March-April (FMA)), El Niño impacts play a much more prominent role. 
By OND, EC is indicated across the Southeast and south-central CONUS, expanding 
to the southwestern CONUS by December-January-February (DJF), as El Niño tends 
to suppress above normal temperature chances across the southern tier. 
Beginning in November-December-January (NDJ) and extending through FMA, near 
normal temperatures are favored for much of the southeastern CONUS where cool 
El Niño impacts and warm trends  are in opposition and observations from the 
closest analogs  to the current El Niño event came in near normal. Conversely, 
confidence increases during the late fall and winter for above normal 
temperatures across the northern tier of the CONUS with probabilities exceeding 
50 percent from the Pacific Northwest to the Northeast by DJF. Two of the 
closest analogs  to the current El Niño also featured a southward extension of 
above normal temperatures across much of the Mississippi Valley and eastern 
Great Plains. As such, a modest tilt (33 to 40 percent chance) toward above 
normal temperatures extends southward across much of the eastern Plains and 
adjacent areas of the Mississippi Valley during DJF and January-February-March 
(JFM). Across Alaska, increased chances of above normal temperatures become 
more focused on eastern parts of the state as we approach late fall and early 
winter, where El Niño composites show the most support. The greatest 
confidence for above normal temperatures (above 50 percent chance) is indicated 
for Southeast Alaska from OND through FMA with confidence decreasing across 
western Alaska where El Niño impacts are more uncertain. Looking further ahead 
to next spring and summer, a transition to a trend-based pattern is forecast, 
with above normal temperatures favored for the eastern and western third of the 
CONUS and the southern tier by April-May-June (AMJ) and persisting through the 
summer into early next fall. Increased chances of warmer than normal conditions 
are forecast across much of Alaska for much of next year, especially across 
eastern parts of the state. 
 
PRECIPITATION 
 
During the SON season, RONI-based El Niño composites show more substantive 
precipitation impacts as opposed to the more muted temperature composites. 
These El Niño composites highlight a robust wet signal from the Southern 
Plains to the Southeast as well as from the southwestern CONUS northeastward to 
the Central Plains. Dynamical model guidance is in agreement with these 
signals, favoring above normal precipitation for most of the southern half of 
the CONUS. However, this widespread wetness across the southern tier of the 
CONUS is in strong opposition to recent trends , which depicts a strong dry 
signal across the Mississippi Valley and eastern Plains. Moreover, the closest 
natural analogs  to the current EP-based El Niño are suggestive of a delayed 
onset of the robust cold season wet signal across the southern tier. As such EC 
is indicated for the SON season across the Lower Mississippi Valley and eastern 
areas of the Southern Plains, where dry trends  are the strongest. Above normal 
precipitation is favored from the southwestern CONUS to the central High 
Plains, broadly consistent with El Niño composites and the potential for 
increased moisture advection from the warmer than normal eastern tropical 
Pacific. Above normal precipitation is also favored for parts of the Southeast, 
where dynamical model guidance is in good agreement and El Niño composites 
tilt wet. Conversely, trends  and El Niño composites slightly favor dry across 
parts of the Northeast and Great Lakes, where below normal precipitation is 
modestly favored. Below normal precipitation is also modestly favored for 
northern and eastern Washington State and adjacent areas of the northern 
Rockies, broadly consistent with dynamical model guidance. Above normal 
precipitation is slightly favored for western Alaska, consistent with 
composites derived from strong to very strong El Niño years. 
 
From late fall through winter, El Niño impacts are expected to increase slowly 
at first before quickly ramping up during the core winter months and especially 
late winter. The closest recent analogs  to this EP-based strong to very strong 
El Niño event are suggestive of a delayed onset of the greatest impacts across 
the southern CONUS. As such, chances for above normal precipitation remain 
modest (generally 33 to 50 percent chance) across the southern tier, Southeast, 
and Central and Southern Plains during OND. A northward extension of these 
modestly elevated above normal precipitation chances is forecast across much of 
the Plains, generally consistent with dynamical model guidance and El Niño 
composites. As we progress deeper into the cold season, the closest analogs  to 
the current El Niño together with dynamical model guidance suggest a rapid 
increase in El Niño impacts across both the West and East coasts as well as 
the southern tier and continued impacts northward across the central Plains. 
The signal is especially robust across much of California and the Southeast. 
Probabilities of above normal precipitation exceed 60 percent across parts of 
the Southeast by NDJ and enhanced probabilities persist through JFM. 
Additionally the tilt toward above normal precipitation extends along almost 
the entire East Coast from NDJ through FMA. Meanwhile, along the West Coast, 
recent EP-based strong El Niños have produced copious precipitation, 
especially in late winter, with 2024 and 1998 being among the wettest 
Februaries in the last 100 years for parts of California. As such, 
probabilities of above normal precipitation were increased significantly to 
above 50 percent across much of coastal California and adjacent areas of 
southern Arizona from DJF through FMA, peaking in coverage during JFM. Notably 
some of the closest analogs  to the current El Niño were wet well north along 
the West Coast, even encroaching much of the southern half of the Pacific 
Northwest. Accordingly, a tilt toward below normal precipitation often 
associated with El Niño was left off the coast and restricted to inland areas 
such as the Northern Rockies and Northern High Plains during the core winter 
months. A slight tilt toward below normal precipitation is also indicated for 
parts of the Great Lakes. EC is indicated farther to the south across the Ohio 
and Tennessee valleys during winter as natural analogs  to the current El Niño 
are not supportive of a robust dry signal. Meanwhile across Alaska, a rapid 
transition from a wetter pattern in SON to a drier pattern by DJF is forecast 
across much of the Mainland, supported by composites from strong to very strong 
El Niño events, with modestly elevated chances of above normal precipitation 
restricted to small portions of southeastern Alaska. By later next Spring, cold 
season El Niño impacts are forecast to gradually ramp down with elevated above 
normal precipitation chances exiting much of the East Coast by AMJ and from the 
entirety of the southwestern CONUS by MJJ. The El Niño based dry signal over 
parts of mainland Alaska times out by AMJ. By next summer, trend dominates the 
outlooks, with the most expansive features being a tilt toward below normal 
precipitation across much of the northwestern quadrant of the CONUS, excluding 
coastal areas, and a tilt toward above normal precipitation across much of the 
Gulf Coast and Southeast. 
 
FORECASTER: Scott Handel 
 
The Climatic normals are based on conditions between 1991 and 2020, following 
the World Meterological Organization convention of using the most recent 3 
complete decades as the climatic reference period.  The probability anomalies 
for temperature and precipitation based on these new normals better represent 
shorter term climatic anomalies than the forecasts based on older normals. 
 
For a description of of the standard forecast tools - their skill- and the 
forecast format please see our web page at 
http://www.cpc.ncep.noaa.gov/products/predictions/long_range/tools.html 
(Use Lower Case Letters) 
Information on the formation of skill of the CAS forecasts may be found at: 
http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Outlook/outlook.shtm 
l 
(use lowercase letters) 
Notes - These climate outlooks are intended for use prior to the start of their 
valid period.  Within any given valid period observations and short and medium 
range forecasts should be consulted. 
 
This set of outlooks will be superseded by the issuance of the new set next 
month on Sep 17 2026 
 
 
1991-2020 base period means were implemented effective with the May 20, 2021 
forecast release. 
$$