Skip Navigation Links www.nws.noaa.gov 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center
 
 

CPC Search
About Us
   Our Mission
   Who We Are

Contact Us
   CPC Information
   CPC Web Team

Official 90-day Outlooks are issued once each month near mid-month at 8:30am Eastern Time. Please consult the schedule of 30 & 90-day outlooks for exact release dates.

Text Discussions
   90day Prognostic
   30day Prognostic
   Hawaiian
   Tools


More Outlooks
    0.5mn AMJ 2023
    1.5mn MJJ 2023
    2.5mn JJA 2023
    3.5mn JAS 2023
    4.5mn ASO 2023
    5.5mn SON 2023
    6.5mn OND 2023
    7.5mn NDJ 2023
    8.5mn DJF 2023
    9.5mn JFM 2024
   10.5mn FMA 2024
   11.5mn MAM 2024
   12.5mn AMJ 2024
    0.5mn Apr 2023


Tools Used (see Discussion for explanation)
   CCA
   OCN
   CMP
   SMT
   POE
 
HOME> Outlook Maps>Seasonal Forecast Discussion
 
Prognostic Discussion for Long-Lead Seasonal Outlooks 
NWS Climate Prediction Center College Park MD
830 AM EDT Thu Mar 16 2023

SUMMARY OF THE OUTLOOK FOR NON-TECHNICAL USERS

In early March 2023, the final La Niña advisory was issued and La Niña has
ended. ENSO-neutral is now present in the equatorial Pacific ocean and favored
to continue through the spring and early summer months. Thereafter, El Niño is
the most likely phase of ENSO from late summer into the autumn months.

The April-May-June (AMJ) 2023 temperature outlook favors above-normal seasonal
mean temperatures for the north slope of Alaska, parts of the Southwest,
southern Plains and Southeast and northward to include the Ohio Valley,
Mid-Atlantic and Northeast. Below-normal temperatures are most likely for
portions of the Northern Plains and central interior West.

The AMJ 2023 precipitation outlook favors above-normal seasonal total
precipitation amounts for portions of the Great Lakes, Ohio Valley,
Mid-Atlantic and Northeast. Below-normal precipitation is most likely for parts
of the far Pacific Northwest and Southwest.

Equal chances (EC) are indicated for areas where seasonal mean temperatures and
seasonal total precipitation amounts are favored 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

La Niña has ended and ENSO-neutral is now present in the equatorial Pacific
Ocean. Equatorial Pacific Ocean sea surface temperatures (SSTs) continued to
warm over the past month with negative anomalies in SST only remaining in an
area near and just east of the Date Line. The most recent weekly value of the
Nino3.4 SST index is -0.1 degrees C. Further east toward the South American
coast, positive anomalies in SST have developed with a region of greater than
+0.5 degrees C departures in the eastern Pacific with the most recent value of
the Niño1+2 SST index of +1.5 degrees C. Below the surface, the 0 - 300 meter
depth equatorial temperature anomalies (i.e., integrated heat content) became
positive in February 2023 and there exists a reservoir of warmer than normal
water spanning a depth from approximately 75 m to 250 m from 130E to 150W with
the maximum anomaly ranging from + 4-6 degrees C.

Although the oceanic indicators for La Niña have decreased in the Pacific
Ocean, there does remain some atmospheric signature and it will likely take
some time for this response to completely disappear. For example, in the past
30 day average, suppressed convection remained present near the Date Line along
the equator and upper-level cyclonic circulations, symmetric about the equator
in both hemispheres, are evident. Trade winds have decreased in magnitude, but
this is in part due to a strong MJO event and associated westerly wind
anomalies crossing the Pacific within the last month.

PROGNOSTIC DISCUSSION OF SST FORECASTS

Forecasts of the Nino3.4 SST index from the NMME are in general agreement for a
transition from small negative anomalies to positive departures from normal of
varying magnitudes ranging from +0.3 to +1.2 degrees C (for the GFDL SPEAR
model) by late summer 2023. The NMME ensemble mean forecast enters El Nino
territory (greater than +0.5 degrees C) approximately during July 2023.

The CPC Niño3.4 SST consolidation forecast follows a similar trajectory as the
NMME models at the start, but hovers near or just below the +0.5 degrees C
threshold during the late summer and early autumn months. Two statistical
components of the CPC Nino3.4 SST consolidated forecast, the CA and CCA
forecasts, predict a much more rapid transition towards El Niño with values of
the Niño3.4 index near or surpassing +1.0 degrees C by autumn 2023.

The official CPC ENSO outlook favors ENSO-neutral through the JJA season with
El Niño favored thereafter at an approximate 60% probability through OND 2023.

PROGNOSTIC TOOLS USED FOR U.S. TEMPERATURE AND PRECIPITATION OUTLOOKS

Given some likely remaining La Niña atmospheric response at times during April
2023, typical La Niña impacts are considered to a minor degree very early in
this set of outlooks (i.e., AMJ 2023). Current anomalous soil moisture and snow
cover/depth are considered and contributed strongly to the outlook in some
locations during the AMJ and MJJ seasons.

Dynamical model forecasts from the NMME and C3S multi-model ensemble systems
are utilized heavily, although precipitation signals are particularly weak from
this month's guidance as compared to normal. Moreover, the Calibration,
Bridging and Merging (CBaM) tool anchored to the NMME forecasts and "bridged"
to the Niño3.4 index is also significantly utilized. The ENSO-OCN forecast tool
that targets impacts from ENSO, as predicted by the CPC consolidation SST
forecast, and long term trends played a large role in many of the outlooks,
especially at longer leads.

Consideration and some slight adjustments consistent with potential development
of El Niño are done in some areas beginning in late summer and autumn 2023, but
any changes are minor at this stage given the uncertainty in the ENSO forecast
initialized during this time of the seasonal cycle (i.e., spring predictability
barrier).

PROGNOSTIC DISCUSSION OF OUTLOOKS - AMJ 2023 TO AMJ 2024

TEMPERATURE

The AMJ 2023 temperature outlook favors above-normal seasonal mean temperatures
from the Southwest eastward to the southern Plains and Southeast as well as
northward to include the Ohio Valley, mid-Atlantic and Northeast. The greatest
odds of above-normal temperatures is for Texas and areas along the Gulf coast
and Eastern Seaboard. There is strong support for warmer than normal
temperatures in this region from nearly all dynamical model guidance and
statistical forecast tools as well as long term positive temperature trends .
Very dry soil moisture conditions and well as above-normal local coastal SSTs,
further enhance these odds for the southern High Plains and Gulf / Atlantic
coasts respectively.

Elevated odds of below-normal temperatures are forecast for the Northern Plains
where abnormally deep snowpack is in place and long term negative temperature
trends exist. Dynamical model forecast guidance from some participant models of
the NMME and C3S suite as well as the CBaM hybrid forecast tool support this
forecast.

A small region of favored below-normal temperatures is highlighted for an area
in the interior western CONUS. Odds tilting toward below-normal temperatures in
this area, however, are very modest. The AMJ and MJJ 2023 temperature outlook
for the western U.S. is challenging due to considerably above normal snowpack
and soil moisture as a result of recent storminess in February and March,
offset by forecasts of warmer than normal temperatures predicted by some
dynamical and statistical forecast guidance. Forecasts from some of the
statistical forecast tools and dynamical models indicate high odds for
above-normal temperatures in the western CONUS from lead 1 onward - perhaps
linked to a more rapid transition to warmer than average equatorial Pacific
SSTs and potential consequent atmospheric response. The higher odds for
above-normal temperatures from these tools seems overdone at the start of this
month's set of outlooks given the highly anomalous snowpack and soil moisture
conditions at the start of AMJ 2023.

Although the impact of enhanced surface wetness (either soil moisture to start
or melting snowpack and consequent elevated soil moisture) is likely to
diminish relatively quickly as the month of May progresses and in June, the
season as a whole may still tilt slightly toward below-normal temperatures. The
monthly temperature outlook for April 2023 favors below-normal temperatures for
considerable areas in the western U.S. Equal-chances (EC) is forecast for much
of the remaining area in the western CONUS due to these competing influences.
There is also support for areas of favored below-normal temperatures in the
western CONUS from the ECMWF model guidance, the CA forecast tool based on soil
moisture, and the CBaM hybrid tool.

Negative trends in sea ice coverage and thickness and so more open water
earlier than normal for ocean areas along the northwest and northern coast of
Alaska favors above-normal temperatures for these areas during AMJ 2023.

Elevated odds for below-normal temperatures remains for portions of the
northern Plains during MJJ 2023, while favored above-normal temperatures
increase in coverage and probabilities across the western CONUS from MJJ
through ASO 2023. Weaker and conflicting signals in the forecast tools increase
uncertainty for the north-central U.S. and so the area forecast as EC increases
from the JJA through OND 2023 seasons.

Primarily beginning in SON 2023, the remaining outlooks are largely based on
the ENSO-OCN forecast tool which is heavily influenced by long-term trends at
these leads with some slight adjustments, at this stage, for the potential
influence of El Niño. For Alaska, increased forecast coverage of favored
above-normal temperatures is depicted from MJJ through SON 2023.

PRECIPITATION

The AMJ 2023 precipitation outlook favors above-normal seasonal total
precipitation amounts for portions of the Great Lakes, Ohio Valley,
Mid-Atlantic and Northeast based on long term positive precipitation trends as
defined by OCN, dynamical model guidance from some participant models from the
NMME and C3S ensemble systems, the CA forecast tool based on anomalous soil
moisture and potential residual La Niña impacts.

Below-normal precipitation is favored for parts of the far Pacific Northwest
and the Southwest U.S. where some dynamical model forecast guidance, the CBaM
hybrid tool, the ENSO-OCN forecast tool and long term negative precipitation
trends supported the outlook.

It is important to note that signals from the dynamical model suite for
precipitation are especially weak for basically all forecast leads for which
forecast guidance is available, even when considering shoulder seasons within
the seasonal cycle as well as the transition to ENSO-neutral.

Favored above-normal precipitation in the eastern CONUS is forecast to shift
eastward and southward with time from MJJ through JJA and then transition
westward by ASO 2023. This evolution is based on long term positive
precipitation trends and to a lesser degree signals from the NMME and C3S model
guidance.

Favored below-normal precipitation forecast for the Pacific Northwest shifts to
include parts of the northern Rockies from MJJ through JAS 2023 - a result of
the ENSO-OCN forecast tool, long term negative precipitation trends and some
dynamical model forecast support. For the Southwest, below-normal precipitation
is most likely to continue during MJJ 2023, albeit with smaller forecast
coverage.

Unlike 2022, there are less climate signals to utilize for prediction of the
first half of the Southwest summer monsoon. Enhanced wetness across the western
CONUS from an extremely wet winter may lead to a potentially delayed start and
less robust monsoon circulation due to perhaps less efficient heating of the
land and so a weaker thermodynamic induced circulation. The CBaM hybrid
forecast tool, does favor below-normal precipitation in the Southwest during
the monsoon season, but there remains considerable uncertainty given the
evolution of ENSO and how that may or may not influence precipitation in the
region this summer.

Climate signals for the state of Alaska for AMJ 2023 are quite weak and
conflicting amongst the tools when present, so EC is forecast for the entire
state. However, above-normal precipitation is most likely for parts of northern
and central Alaska beginning in MJJ 2023 and continuing through the remainder
of 2023. Model guidance and more open water earlier in the seasonal cycle are
the basis for these highlighted areas.

Primarily long term precipitation trends and slight tilts in deference to
potential EL Niño development are used in making the remainder of the
precipitation outlooks through AMJ 2024.

FORECASTER: Jon Gottschalck

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 Cas e 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 Apr 20 2023


1991-2020 base period means were implemented effective with the May 20, 2021
forecast release.
$$

NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
5200 Auth Road
Camp Springs, Maryland 20746
Climate Prediction Center Web Team
Page last modified: January 17, 2006
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act
About Us
Career Opportunities