Issued 7 November 2013 Forecast maps Forecast Background ENSO update Current State of the global climate SST Forecasts Summary Methodology The forecasts are subjectively derived from canonical correlation analysis CCA seasonal forecast runs the NCEP CFS the National ID: 357788
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Slide1
Consolidated Seasonal Rainfall Guidance for Africa, November 2013 Initial ConditionsIssued 7 November 2013
Forecast maps
Forecast Background
ENSO update
Current State of the global climate
SST Forecasts
SummarySlide2
Methodology
The forecasts are subjectively derived from canonical correlation analysis (CCA) seasonal forecast runs, the NCEP CFS, the National
Multimodel
Ensemble (NMME) forecasts, and the International
Multimodel
Ensemble (IMME) forecasts
Polygons are drawn for areas, where there is an agreement between the models to tilt the odds to favor one category over another. Preference is sometimes given to the CCA when skill is moderate to high.
The NMME models include: the NOAA CFS, the Canadian models, NOAA GFDL, NCAR, NASA
The IMME models include: the ECMWF, the UK MO, and
Meteo
France
Forecasts are expressed in probabilistic terms to convey uncertainty.Slide3
Seasonal Rainfall Guidance for Africa,
Oct
IC, Issued
7 Nov
2013, Valid Nov 2013 – May 2014
Based on an assessment of CCA forecasts, CFSv2, and NMME, the use of climatology is suggested for Africa from zero to 4 months lead.Slide4
CPC ENSO Update
CPC ENSO
Alert
System Status
: Not Active(updated 7 November 2013)Synopsis: ENSO-neutral is expected through the Northern Hemisphere Spring 2014http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/index.shtmlSlide5
SST was slightly
below
normal across the equatorial eastern Pacific.
Above-average SST persisted across
the northern
Atlantic
.
Current State of the Global Ocean
SST Anomaly (top) for
October
2013
and Tendency (bottom) for October minus September
Positive SST anomalies were observed over parts of the Indian Ocean and the northern Pacific Ocean.
SST
tendency
was
positiveacross portions of equatorial easternPacific.
Last Month
Positive SST tendency
was
observed over
the northern Indian
Ocean.Slide6
SST was
below
normal in the
equatorial eastern
Pacific.
Positive SST anomalies
persisted
over many parts of
the northern
Atlantic.
Current State of the Global Ocean
Positive SST anomalies were present over much of
the Indian Ocean and parts of the western Pacific.
Weekly SST Anomaly
27 Oct – 02 Nov 2013 and
Tendency for 27 Oct – 02 Nov 2013 minus 20 – 26 Oct 2013
SST tendency was negative over the North Atlantic Ocean
Last Week
SST
tendency was positive over
parts of the Indian
OceanSlide7
OLR Anomaly,
October
2013
Negative OLR anomalies (enhanced convection and precipitation, blue shading) were observed
over portions of West Africa, the Greater Horn of Africa and near the Mozambique Channel in Africa, over much of India and western Pacific extending into Indonesia, Papa New Guinea and western Australia, and over Bolivia and portions of Brazil.
Precipitation
was suppressed (orange-red shading) over
portions of the Lake Victoria and southern Africa regions in Africa, many parts of the Indian Ocean, eastern Australia and over the Central Pacific Ocean. Slide8
Low Level 850
mb
Wind Anomaly
Stronger than normal cross-equatorial flow was observed near the Horn of Africa and India. Anomalous cyclonic circulation was present over western Pacific.
Westerly anomalies persisted across Equatorial eastern Pacific.Slide9
Upper Level 200
mb
Wind AnomalySlide10
Tropical Atlantic SSTSlide11
Indian Ocean SSTSlide12
Monitoring the
Indian Ocean Dipole (IOD
)
The IOD index remains
neutral.Slide13
Time
Longitude
Monitoring the Madden Julian Oscillation
Over the last few days
,
the
MJO index emerged in Phase 8 and has exhibited
an eastward
propagation . The ensemble GFS indicates a
gradual weakening
MJO signal during the upcoming
weeks.Slide14
Summary of State of the Global Climate in October 2013
Neutral ENSO state continued to prevail in October. Equatorial sea surface temperatures (SST) anomalies continued to be negative across the eastern Pacific and positive
over parts of
the western
Pacific. SST was above-average over the northern Atlantic and portions of the Indian Ocean. The IOD index remained near neutral during October 2013.Precipitation was above average over parts of West Africa, the Greater Horn of Africa, and along the Mozambique Channel. Precipitation was also enhanced over much of India and the western Pacific, as well as central South America. In contrast, precipitation was suppressed in the vicinity of Lake Victoria and
parts of southern Africa. Precipitation was also suppressed over southeastern Indonesia. Slide15
Most models predict
ENSO-neutral
continuing into Northern Hemisphere spring 2014.
The consensus forecast favors ENSO-neutral through
the Northern Hemisphere
Spring 2014
IRI/CPC NINO3.4 Forecast Plume
IRI Probabilistic ENSO Prediction for NINO3.4 Region
Season
La Niña
Neutral
El Niño
OND 2013
5%
95%
0%
NDJ 2014
6%
93%
1%
DJF 2014
7%
91%
2%
JFM 2014
6%
90%
4%
FMA 2014
6%
82%
12%
MAM 2014
6%
73%
21%
AMJ 2014
9%
58%
33%
MJJ 2014
11%
49%
40%
JJA 2014
10%
48%
42%Slide16
Global SST Outlook: NCEP
CFS.v2
Forecast
Initial Conditions
22 – 31 October 2013
Nov 2013-Jan 2014
Dec 2013-Feb 2014
Jan 2013-Mar 2014
Feb-Apr
2014
Caution
: Ocean areas
with skill less than 0.3
are shaded in gray
CFS.v2 predicts
neutral ENSO conditions to persist through the northern hemisphere fall season.
Additional forecast resources are found here
:
http://www.cpc.ncep.noaa.gov/products/african_desk/cpc_intl/index.shtmlhttp://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/
Mar-May 2014Slide17
Global SST Outlook: NMME (left) and IMME (right)
NDJ
NDJ
DJF
DJF
http://www.cpc.ncep.noaa.gov/products/NMME/seasanom.shtmlSlide18
NDJ
NDJ
DJF
DJF
http://www.cpc.ncep.noaa.gov/products/NMME/seasanom.shtml
Global Precipitation Outlook: NMME (left) and IMME (right)Slide19
IOD Outlook (source: Australian Bureau of Meteorology)
The IOD
signal is expected to remain week through the Northern Hemisphere Winter.Slide20Slide21
Summary
SST
predictions favor ENSO-neutral to continue into northern hemisphere Spring 2014.
Precipitation forecast skill is very low and therefore the use of climatology is suggested for Africa.Additional forecast resources can be found here: http://www.cpc.ncep.noaa.gov/products/african_desk/cpc_intl/index.shtmlhttp://www.cpc.ncep.noaa.gov/products/NMME/http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/
http://iri.columbia.edu/our-expertise/climate/forecasts/seasonal-climate-forecasts
/