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

Consolidated Seasonal Rainfall Guidance for Africa, June 2013 Initial Conditions Issued 9 July 2013. Forecast maps Forecast Background ENSO update Current State of the global climate SST Forecasts Summary. Methodology.

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

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  1. Consolidated Seasonal Rainfall Guidance for Africa, June 2013 Initial ConditionsIssued 9 July 2013 • Forecast maps • Forecast Background • ENSO update • Current State of the global climate • SST Forecasts • Summary

  2. 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.

  3. Seasonal Rainfall Guidance for Africa, Jun IC, Issued 9 July 2013, Valid Jul-Sep 2013 and Aug-Oct 2013 For Jul-Sep, the forecasts call for a slightly elevated chance for above average rainfall over the central areas of the Sahel, including eastern Burkina Faso and southwestern Niger. For Aug-Oct, there is an increased chance for above average rainfall over western Kenya and eastern Uganda. Aug-Oct 2013, One Month lead Jul-Sep 2013, Zero Month lead

  4. Seasonal Rainfall Guidance for Africa, June IC, Issued 9 July 2013, Valid Sep-Nov 2013 and Oct-Dec 2013 For both Sep-Nov and Oct-Dec, the forecasts call for an elevated chance for above average rainfall over western Kenya and eastern Uganda. Sep-Nov 2013, Two Months lead Oct-Dec 2013, Three Months lead

  5. CPC ENSO Update • CPC ENSO Alert System Status: Not Active (updated 5 July 2013) • Synopsis:ENSO-neutral is favored through the Northern Hemisphere summer 2013. http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/index.shtml

  6. Current State of the Global Ocean Last Month SST Anomaly (top) for June 2013 and Tendency (bottom) for June minus May Positive SST anomalies persisted across western Pacific and eastern Indian Ocean. Below normal SST persisted across the eastern Pacific. SST was slightly above-average across the equatorial Atlantic. SST tendency was negative over Bay of Arabian Sea and Bay of Bengal, while positive tendencies were observed over central and southern Indian Ocean. SST tendency was positive Across portions of equatorial eastern Pacific.

  7. Current State of the Global Ocean Last Week Weekly SST Anomaly 30 June – 6 July 2013 and Tendency for 30 June – 6 Jul minus 23 – 29 June SST was below normal in the equatorial eastern Pacific. Positive SST anomalies persisted in the eastern sector of the tropical North Atlantic. Positive SST anomalies were present in the eastern Indian Ocean and western Pacific. SST tendency was positive over the eastern tropical Pacific. SST slightly decreased Across southwestern Indian Ocean

  8. OLR Anomaly, June 2013 Negative OLR anomalies (enhanced convection and precipitation, blue shading) were observed over India, the Arabian Sea and Bay of Bengal, parts of the Maritime Continent region, extending into eastern Indian Ocean and Australia, and portions of Peru, Bolivia and Brazil. Precipitation was suppressed (orange-red shading) over equatorial Africa, Central Indian Ocean, and the tropical central and eastern Pacific.

  9. Low Level 850 mb Wind Anomaly Stronger than normal cross-equatorial flow was observed over northwestern Indian Ocean. Weak easterly (westerly) wind anomalies were present over the equatorial western (eastern) Pacific. There was an amplification of the subtropical ridges across both hemispheres over the Atlantic as evidenced by the anomalous anticyclonic circulation in the northern and southern Atlantic.

  10. Upper Level 200 mb Wind Anomaly 200hPa The 200 hPa wind anomaly map features a strengthening of the Mascarene high pressure system with the presence of an anomalous anticyclonic circulation over the southern Indian Ocean. Also, noticeable is the strengthening of the Tibetian High as evidenced by the anomalous anticyclonin circulation over Asia and Africa.

  11. Monitoring the Madden Julian Oscillation Time Moderate MJO has been observed over the past several weeks. GEFS bias corrected indicates a gradual weakening of the current MJO signal. Longitude

  12. Summary of State of the Global Ocean in June 2013 • Neutral ENSO state continued to prevail in June. Equatorial sea surface temperatures (SST) anomalies were slightly negative across the eastern Pacific. • Positive SST anomalies but weakened over the tropical North Atlantic and the western Pacific. SST was above normal over the south central Indian Ocean, but below normal along coastal East Africa. • SST anomalies over the past week featured warming along coastal West Africa and cooling over the equatorial eastern Pacific. • Precipitation was significantly above average over India and parts of southeast Asia, while moderately enhanced over portions of tropical central Africa. Precipitation was suppressed along the Gulf of Guinea and parts of equatorial central Africa.

  13. IRI/CPC NINO3.4 Forecast Plume • Most of the models predicted ENSO-neutral in the coming Northern Hemisphere summer and autumn. • The consensus forecast favors ENSO-neutral conditions in the summer-autumn 2013.

  14. Global SST Outlook: NCEP CFS.v2 Forecast Initial Conditions 21 – 30 June 2013 Jul-Sep 2013 Oct-Dec 2013 Caution: Ocean areas with skill less than 0.3 are shaded in gray Aug-Oct 2013 Nov 2013-Jan 2014 Sep-Nov 2013 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.shtml http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/

  15. Global SST Outlook: NMME (left) and IMME (right) JAS JAS ASO ASO http://www.cpc.ncep.noaa.gov/products/NMME/seasanom.shtml

  16. Global Precipitation Outlook: NMME (left) and IMME (right) JAS JAS ASO ASO http://www.cpc.ncep.noaa.gov/products/NMME/seasanom.shtml

  17. Summary • Neutral El Nino Southern Oscillation (ENSO) conditions continue to prevail. Sea surface temperature (SST) was slightly above normal along coastal West Africa and over the western Pacific. • SST predictions favor ENSO-neutral to continue through the northern hemisphere summer and autumn of 2013. • Precipitation forecasts are mostly driven by regional SST and not ENSO. They are expressed in probabilistic terms to convey uncertainty. • Additional forecast resources can be found here: http://www.cpc.ncep.noaa.gov/products/african_desk/cpc_intl/index.shtml http://www.cpc.ncep.noaa.gov/products/NMME/ http://origin.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/

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