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
. The predictions from the National Centers for
Environmental Prediction (NCEP) Coupled Forecast System Model (CFS03) are
presented in Figs. F3 and F4a,
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
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.
El Niño conditions likely through the end of 2006
and into early 2007.
By early September equatorial SST anomalies greater than +0.5ºC were
observed in most of the equatorial Pacific, with anomalies exceeding +1.0ºC in the central Pacific between
165ºE and 170ºW (Fig. T18).
The latest SST departures in the Niño
regions are all greater than +0.5 (Table 2, Fig. T5).
Beginning in February the basin-wide upper ocean heat content
increased, and since early April positive anomalies have been observed.
Since early July weaker-than-average low-level
equatorial easterly winds have been observed across most of the equatorial
Pacific (Fig. T20).
In August the Southern
Oscillation Index (SOI) was
negative for the fourth consecutive month (Fig. T1).
these oceanic and atmospheric anomalies are consistent with developing warm
episode (El Niño) conditions in the
Over the past several months
most of the statistical and coupled model forecasts have trended towards
warmer conditions in the tropical Pacific through the Northern Hemisphere
latest NCEP coupled forecast system (CFS) predictions indicate El
Niño conditions for the remainder of
2006 and into the NH spring 2007. More
than half of the other statistical and coupled model predictions are also
favoring El Niño conditions during the same period (Figs. F1,
F2, F3, F4a,
F4b, F5, F6,
F7, F8, F9,
F10, F11, F12
recent conditions (weaker-than-average easterly winds over the central
equatorial Pacific) and warming trends in observed oceanic conditions support
impacts from the developing El Niño are already
evident in the pattern of tropical precipitation. During the last 30 days
drier-than-average conditions have been observed across all of
are usually the first areas to experience ENSO-related impacts. This dryness
can be expected to continue, on average, for the remainder of 2006.
Typical El Niño
effects are likely to develop over
during the upcoming
winter season. Those include warmer-than-average temperatures over western
, and over the western
conditions are likely over portions of the U.S. Gulf Coast and
drier-than-average conditions can be expected in the
updates of SST, 850-hPa wind, OLR and features of the equatorial subsurface
thermal structure are available on the
Center homepage at: