Consolidated Seasonal Rainfall Guidance for Africa, Jan 2013 Initial Conditions

• Summary

• Forecast maps

• Forecast Background– ENSO update– Current State of the global climate– SST Forecasts

• Summary

Seasonal Rainfall Guidance for Africa, Dec IC, Issued 5 Feb 2013, Valid Feb-Apr 2013, Mar-May 2013

Feb-Apr 2013, Zero Month lead

The forecasts call for a slightly elevated chance for above average rainfall to occur over northern Mozambique and Malawi during Feb-Apr 2013. There is also a slightly increased chance for above average rainfall over northern Namibia and southwestern Angola, as well as along coastal Guinea. For Mar-May 2013, there is a slightly increased chance for above average rainfall over northeastern Tanzania. Climatology is suggested everywhere else.

Mar-May 2013, One Month lead

CPC ENSO Update

• CPC ENSO Alert Status: Not Active(updated 7 Feb 2013)

• Synopsis: ENSO-neutral is favored through Northern Hemisphere spring 2013.

Current State of the Global Ocean

SST Anomaly (top) and Tendency (bottom) for January 2013

The change in SST anomalies is negativein the equatorial Pacific, suggesting a decrease in SST

SST weakened acrossThe central IndianOcean, though slightlyPositive anomaliesPersisted along coastalEast Africa.

SST was below averagein the Pacific along the equator east of thedateline.

SST remained elevated Along coastal Angola, But has wekened overThe past month.

Tropical Atlantic SST off the coast of West Africa and in the Gulf of Guinea continued to increase

Weekly SST Anomaly and Tendency for 27 Jan – 2 Feb 2013

SST increased over theEastern Indian Oceanand decreased over theWestern Indian Ocean. Ocean

SST off the coast of West Africa decreased,but remained elevated. SST over the Gulf of Guinea increased.

SST continued toDecrease over theCentral Pacific.

Current State of the Global Ocean

200hPa

850hPa

Wind Anomaly

Anomalous low-level (850-hPa) winds were near average across the central and eastern Pacific. Anomalous wind convergence was evident over the Maritime continent.

Anomalous upper-level (200 hPa) winds were westerly over the eastern half of the Pacific. Winds were westerly over the western Indian Ocean and near average over the eastern Indian Ocean.

OLR Anomaly, January 2013

Negative OLR anomalies (enhanced convection and precipitation, blue shading) were observed over much of the equatorial western Pacific and in the areas including Indonesia and the Philippines. This represents an eastward shift compare to the month December and reflects the strong MJO events of the past several weeks. Precipitation was suppressed (orange-red shading) over the eastern and central Indian Ocean. In Southern Africa, a zonal dipole with enhanced (suppressed) precipitation over Mozambique (Namibia and Angola) was evident. Precipitation was also enhanced over northeastern Brazil and suppressed in the south.

Summary of State of the Global Ocean in Jan 2013

• Neutral ENSO state continued to prevail in January. Equatorial sea surface temperatures (SST) anomalies were slightly negative across the Pacific east of the dateline.

• Over the past month, SST remained slightly elevated over the western Pacific and along the east coast of Africa with a warming tendency along the Mozambique Channel.

• In the Atlantic, SST remained above normal off the coast of West Africa and over the Gulf of Guinea. SST off the coast of Angola decreased, but remained higher than normal.

• Upper-level zonal winds were westerly over the eastern Pacific, while lower-level were near average across the central Pacific. Precipitation was enhanced over the western Pacific north of the equator and suppressed over eastern Australia and eastern Indian Ocean. This represented a eastward shift of the large scale convection indicative of the influence of a moderately strong MJO event during January.

CPC/IRI Probabilistic ENSO Outlook(updated 10 Jan 2012)

ENSO-neutral is favored through mid-2013.

CPC ENSO Monitoring Team

Pacific Niño 3.4 SST Outlook

Figure provided by the International Research Institute (IRI) for Climate and Society (updated 15 Jan 2012).

• Most models predict the persistence of current Niño-3.4 values, with ENSO-neutral (-0.5ºC to +0.5ºC) continuing through the Northern Hemisphere summer 2013.

CPC ENSO Monitoring Team

Feb-Apr 2013

Mar-May 2013

Apr-Jun 2013

May-Jul 2013

Global SST Outlook: NCEP CFS.v2 Forecast Initial Conditions 25 Jan – 3 Feb 2013

CFS.v2 predicts above normal SST over the western Pacific, the eastern Indian Ocean,and the south tropical Atlantic. Near average conditions are predicted for the tropical Pacific and the central Indian Ocean through the summer season.Additional forecast resources are found here:http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/

Caution: Ocean areaswith skill less than 0.3are shaded in gray

Jun-Aug 2013

Global SST Outlook: NMME (left) and IMME (right)Next update Jan 10

FMA FMA

MAM MAM

http://www.cpc.ncep.noaa.gov/products/NMME/seasanom.shtml

FMA FMA

MAM MAM

http://www.cpc.ncep.noaa.gov/products/NMME/seasanom.shtml

Global Precipitation Outlook: NMME (left) and IMME (right)Next update Jan 10

Summary• Neutral El Nino Southern Oscillation (ENSO) conditions continue to

prevail. However, Sea surface temperature (SST) was below normal over the eastern half of the Pacific and above normal over the western Pacific.

• SST was above normal over the eastern Atlantic along the coast of Africa and along the east coast of Africa in the western Indian Ocean.

• SST predictions favor ENSO-neutral and most models do not predict significant departures from climatology in the global tropical oceans

• Neutral ENSO conditions will contribute to a low confidence in the precipitation forecasts for the coming seasons.

• Additional forecast resources can be found here: http://www.cpc.ncep.noaa.gov/products/NMME/