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.
are expected during the next 3-6 months.
Equatorial SSTs were near average
in most areas between 180°W and the South
American coast during August, while positive anomalies persisted between
Indonesia and 180°W (Figs T9 and T18).
The SST departures in the Niño 3, Niño 3.4, and Niño 1+2 regions were
quite small, while positive departures (+0.4°C) persisted in the Niño 4
region (Table T2 and Fig. T5).
The general decrease in surface and subsurface temperature anomalies observed
during the last several months (Figs. T9, T15
and T17), has been accompanied by
stronger-than-average easterly winds (Fig. T7)
and near-average convection (Figs. T8 and T25)
over the central equatorial Pacific, consistent with ENSO-neutral conditions.
The value of the Oceanic Niño Index (ONI; 3-month
running mean average of SST anomalies in the Niño 3.4 region – computed
using the Extended Reconstructed SST version-2 data set) for June-August 2005
is +0.2°C, which indicates ENSO neutral conditions. The large spread of the
most recent statistical and coupled model forecast (Figs. F1,
F2, F3, F4a,
F4b, F5, F6,
F7, F8, F9,
F10, F11, F12
from weak La Niña to weak El Niño indicates
considerable uncertainty. However, current conditions and recent observed
trends support a continuation of ENSO-neutral conditions for the next 3-6
updates of SST, 850-hPa wind, OLR and features of the equatorial subsurface
thermal structure are available on the
Center homepage at: