Issued 10 April 2015 Forecast Background ENSO update Current State of the global climate SST Forecasts Regional Rainfall Forecast maps Summary CPC ENSO Update CPC ENSO Alert System Status ID: 275998
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Slide1
Consolidated Seasonal Rainfall Guidance for Global Tropics, April 2015 Initial ConditionsIssued 10 April 2015
Forecast Background
ENSO update
Current State of the global climate
SST Forecasts
Regional Rainfall Forecast
maps
SummarySlide2
CPC ENSO Update
CPC ENSO
Alert
System Status
:
El Niño Advisory
Synopsis:
There is an approximately 70% chance that El Niño will continue through Northern Hemisphere summer 2015, and a greater than 60% chance it will last through autumn.
(Updated on April 9, 2015)
http
://
www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/index.shtmlSlide3
Equatorial
SSTs were
above average
across the western
Pacific.
Current State of the Global Ocean
SST Anomaly (top) for
March 2015 and Tendency (bottom) for March 2015 minus February 2015
Positive SST anomalies were observed across the central and southern Indian Ocean.
Changes in equatorial SST anomalies were negative across the equatorial Pacific.
Last Month
SST tendency was positive across the western and southern Indian Ocean.Slide4
SST was
above average
across
the equatorial
eastern and central Pacific
, with larger anomalies present near the Date Line.
Positive
SST anomalies were present over much of the Indian Ocean.Weekly SST Anomaly 29 March – 4 April 2015 andTendency for 29 March – 4 April 2015 minus
22 - 28 March 2015 Last Week
SST tendency was positive over
the western Indian Ocean.
Current State of the Global Ocean
Positive SST tendency was observed over the eastern Pacific.Slide5
OLR Anomaly,
March 2015
Negative OLR anomalies (enhanced convection and precipitation, blue shading)
was
observed along the Gulf of Guinea coastline, central Africa, and parts of southern Africa. Convection was also enhanced over western Australia, the central Pacific, and parts of South America
.
Precipitation
was suppressed (orange-red shading) over northern southern Africa, eastern Indian Ocean, the Maritime Continent, and the eastern Pacific Ocean..Slide6
Low Level 850 mb Wind Anomaly
Anomalous low-level (850-hPa) westerly winds were located over the western and central equatorial Pacific.Slide7
Upper Level 200 mb Wind Anomaly
Anomalous upper-level (200-hPa) westerly winds were apparent over the eastern Pacific, while anomalous easterlies were observed near the Date Line.Slide8
Monitoring the Madden Julian
Oscillation
The GFS ensemble RMM Index forecasts depict a weakening of the signal over the next week, as destructive interference grows between the ENSO signal and the
subseasonal
variability.
Time
Recently
, eastward propagation of a strong
negative
(positive
) OLR
anomalies propagating over the
Maritime
Continent and far West
Pacific.
Negative anomalies persisted near the Date Line.Slide9
Evolution of Indian Ocean SST Indices
The Indian Ocean Dipole (IOD)
returned to near average values in late March and early April,
with
the
latest weekly index value
as of 5 April 2015 0.05 °C.Slide10
Summary of State of the Global Climate in March 2015
El Niño conditions are present
. The
most recent
Ocean Nino Index (ONI)
value (January – March 2015) is 0.6oC. Positive sea surface temperature (SST) anomalies
continued across the central Pacific. Above-average SSTs were observed across the central and southern Indian Ocean. The Indian Ocean Dipole (IOD) returned to near neutral values in late March and early April.
Enhanced precipitation was observed along the Gulf of Guinea coastline, central Africa, and parts of southern Africa. Convection was also enhanced over western Australia, the central Pacific, and parts of South America.Convection was suppressed over northern southern Africa, eastern Indian Ocean, the Maritime Continent,
and the eastern Pacific Ocean.Slide11
Nino region SST departures
Eq. Subsurface temperature Anomalies
Niño 4
0.9ºC
Niño 3
0.9ºC
Niño 1+2
0.5ºC
The latest weekly SST departures
:
Niño
4
=
1.1ºC Niño 3.4
=
0.7ºC
Niño 3
=
0.6ºC Niño 1+2
=
1.4ºC
Recently, negative anomalies in the eastern Pacific have diminished in strength and extent.Slide12
About half of the models indicate Niño 3.4 SST anomalies will remain greater than or equal to +0.5C through the end of 2015. Many other models (mostly statistical models) predict ENSO-neutral conditions.
IRI/CPC NINO3.4 Forecast Plume
Season
La Niña
Neutral
El Niño
MAM 2015
~0%
26%
74%
AMJ 2015
~0%
29%
71%
MJJ 2015
1%
29%
70%
JJA 2015
2%
29%
69%
JAS 2015
2%
30%
68%
ASO 2015
3%
33%
64%
SON 2015
5%
34%
61%
OND 2015
6%
34%
60%
NDJ 2015
7%
34%
59%Slide13
Global SST Outlook: NCEP
CFS.v2
Forecast
Initial Conditions
29 March 2015 – 07 April 2015
May - Jul 2015
Jun - Aug 2015
Jul - Sep 2015
Aug - Oct 2015
Caution
: Ocean areas
with skill less than 0.3
are shaded in gray
Sep - Nov 2015
CFS.v2 predicts
higher than normal SST across equatorial central and eastern Pacific Ocean.
Additional forecast resources are found here:
http
://
www.cpc.ncep.noaa.gov/products/african_desk/cpc_intl/index.shtml
http://
www.cpc.ncep.noaa.gov/products/CFSv2/htmls/glbSSTe3SeaMask.htmlSlide14
Global SST Outlook:
NMME (top panel) & IMME (bottom panel)
May - Jul 2015
Jun - Aug 2015
Jul - Sep 2015
NMME
I
MME
NMME and IMME models predict higher
than normal SST across
the equatorial central and eastern Pacific
Ocean.Slide15Slide16
IOD Outlook (source: Australian Bureau of Meteorology)
Model
outlooks
suggest
that the
Indian
Ocean
dipole (IOD) will
remain
near average through the northern hemisphere spring and summer 2015.Slide17
Rainfall Guidance, Africa: NMME
,
Precipitation Skill Masked Std. Anomalies,
(
01 – 08
April
2015 IC
)
May - Jul 2015
Jun - Aug 2015
Jul – Sep 2015
Aug – Oct 2015
The forecasts call for climatology over much of Africa. There is a slight tilt in the odds to favor above (below) average rainfall over portions of the Sahel (Guinea coast) in Jul to Sep and Aug to Oct seasons.
Individual model forecasts can be found here:
http://www.cpc.ncep.noaa.gov/products/international/nmme/nmme1.shtml
Gray shade indicates areas where skill is lower than 0.3.Slide18
Rainfall Guidance,
CAM and Caribbean: NMME, Precipitation Skill Masked Std. Anomalies,
(
01 – 08 April 2015 IC
)
The forecasts call
for
a slight to moderate tilt in the odds to favor below-average rainfall over portions of Central America and the Caribbean.
Individual model forecasts can be found here:
http://www.cpc.ncep.noaa.gov/products/international/nmme/nmme1.shtml
Gray shade indicates areas where skill is lower than 0.3.
May - Jul 2015
Jun - Aug 2015
Jul – Sep 2015
Aug – Oct 2015Slide19
Rainfall Guidance, South America:
NMME, Precipitation Skill Masked Std. Anomalies
,
(
01 – 08 April 2015 IC
)
The forecasts
call
for a slight to moderate tilt in the odds to favor below average
rainfall
along the northern coast of South America. In contrast, there is a slight to moderate tilt in the odds to favor above-average rainfall over portions of Bolivia, Paraguay and Brazil.
Individual model forecasts can be found here:
http://www.cpc.ncep.noaa.gov/products/international/nmme/nmme1.shtml
Gray shade indicates areas where skill is lower than 0.3.
May - Jul 2015
Jun - Aug 2015
Jul – Sep 2015
Aug – Oct 2015Slide20
Rainfall Guidance, Central Asia:
Precipitation Skill Masked Std. Anomalies,
(
01 – 08 April 2015 IC
)
The forecasts call for
climatology over much of Central Asia, except
for a slight to moderate tilt in the odds to favor
above average
rainfall
over
Turkey, northern Iran, southern Turkmenistan, northern Afghanistan and the neighboring areas in May to Jul season.
In contrast, there a slight to moderate tilt in the odds to favor below-average rainfall over portions of Pakistan and southern Iran.Individual model forecasts can be found here:
http://www.cpc.ncep.noaa.gov/products/international/nmme/nmme1.shtmlGray shade indicates areas where skill is lower than 0.3.
May - Jul 2015
Jun - Aug 2015
Jul – Sep 2015
Aug – Oct 2015Slide21
Summary
El Niño conditions are
present.
Above-average Sea surface temperatures (SST) was observed over
the central Pacific
Ocean. Positive SST anomalies were observed over the central and southern Indian Ocean.There is an approximately 70% chance that El Niño will continue through Northern Hemisphere summer 2015, and a greater than 60% chance it will last through autumn.
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/