Forecast Forum
The canonical correlation analysis (CCA) forecast of
SST in the central Pacific (Barnett et al. 1988, Science, 241,
192‑196; Barnston and Ropelewski
1992, J. Climate, 5, 1316‑1345), is shown in Figs. F1 and F2. This forecast is produced routinely by the
Prediction Branch of the Climate Prediction Center. The
predictions from the National Centers for Environmental Prediction (NCEP)
Coupled Forecast System Model (CFS03) are presented in Figs. F3 and
F4a, F4b. Predictions from the
Markov model (Xue, et al. 2000: J. Climate, 13,
849‑871) are shown in Figs. F5 and F6. Predictions from the latest version of the
LDEO model (Chen et al. 2000: Geophys. Res.
Let., 27, 2585‑2587) are shown in Figs. F7
and F8. Predictions using linear inverse modeling (Penland and Magorian 1993: J.
Climate, 6, 1067‑1076) are shown in Figs. F9 and F10. Predictions from the Scripps / Max Planck
Institute (MPI) hybrid coupled model (Barnett et al. 1993: J. Climate, 6,
1545‑1566) are shown in Fig. F11.
Predictions from the ENSO‑CLIPER statistical model (Knaff and Landsea 1997, Wea.
Forecasting, 12, 633‑652) are shown in Fig. F12. Niño 3.4 predictions are summarized in Fig.
F13, provided by the Forecasting and Prediction Research Group of the IRI.
The CPC and the contributors to the Forecast Forum caution
potential users of this predictive information that they can expect only modest
skill.
ENSO Alert System Status: El Niño Watch
Outlook:
While
ENSO-neutral is favored for Northern Hemisphere spring, the chances of El Niño
increase during the remainder of the year, exceeding 50% by summer.
Discussion:
ENSO-neutral continued
during March 2014, but with above-average sea surface temperatures (SST)
developing over much of the eastern tropical Pacific as well as near the
International Date Line (Fig. T18). The SSTs were below average in
the Niño1+2 region, near average but rising in Niño3
and Niño3.4 regions, and above average in the Niño4 region (Table T2). A
significant downwelling oceanic Kelvin wave that was
initiated in January greatly increased the oceanic heat content to the largest
March value in the historical record back to 1979, and produced large positive
subsurface temperature anomalies across the central and eastern Pacific (Fig.
T17). Also
during March, low-level westerly wind anomalies were observed over the central
equatorial Pacific. Convection was
suppressed over western Indonesia, and enhanced over the central equatorial
Pacific (Fig. T25). Although these atmospheric and oceanic
conditions collectively reflect ENSO-neutral, they also reflect a clear
evolution toward an El Niño state.
The model predictions of
ENSO for this summer and beyond are indicating an increased likelihood of El
Niño this year compared with last month.
Most of the models indicate that ENSO-neutral (Niño-3.4 index between
-0.5°C and 0.5°C) will persist through much of the remainder of the Northern
Hemisphere spring 2014 (Figs. F1-F13), with many models
predicting the development of El Niño sometime during the summer or fall. Despite this greater
model consensus, there remains considerable uncertainty as to when El Niño will
develop and how strong it may become. This uncertainty is amplified by the
inherently lower forecast skill of the models for forecasts made in the spring.
While ENSO-neutral is favored for Northern Hemisphere spring, the chances of El
Niño increase during the remainder of the year, and exceed 50% by the summer.
Weekly
updates of oceanic and atmospheric conditions are available on the Climate
Prediction Center homepage (El
Niño/La Niña Current Conditions and Expert Discussions).