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.
surface temperature (SST)
anomalies decreased throughout the eastern equatorial Pacific
during July (Figs. T9, T18).
By the end of the month, equatorial SSTs
were near average in most areas between 180°W
and the South American coast, while positive anomalies persisted between
and 180°W (Fig. T18).
The decrease in SST anomalies in the eastern equatorial Pacific during July
was reflected by a decrease in the SST departures
in the Niño 3, Niño 3.4, and Niño 4 regions (Table T2,
Fig. T5). By
the end of July the patterns of tropical convection (Fig. T25),
low-level winds (Fig. T20), upper-level
winds (Fig. T21), SST (Fig. T18)
and subsurface ocean temperatures (Fig. T17)
were near average, indicating 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 May-July
2005 is +0.3°C,
which indicates ENSO neutral conditions.
The large range (weak La Niña to weak El Niño) in the statistical
and coupled model forecasts (Figs. F1,
F2, F3, F4a,
F4b, F5, F6,
F7, F8, F9,
F10, F11, F12
indicates considerable uncertainty. However, current conditions and recent
trends support the 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