Date and Period of Forecast  In January 2000, the IRI Experimental Forecast Division prepared a Climate Outlook for January-March 2000.  Here we provide a subset of the January Net Assessment Forecast.  The complete forecast, which includes global forecasts for April-June 2000,  can be found at http://iri.columbia.edu/climate/forecast/net_asmt/.
UncertaintiesThis Climate Outlook is dependent on the quality of the SST predictions [link to Ocean below]. For the tropical Pacific, these predictions can be expected to provide useful information, but there is some uncertainty concerning the detailed evolution of SSTs.  Spread in global SST predictions is a source of uncertainty in the Outlook provided here. The procedures, models, and data used to derive this Climate Outlook may be somewhat different from those used by National Meteorological Services in particular regions and may differ from the official forecasts issued in those areas.
Regional Influences  The current status of seasonal-to-interannual climate forecasting allows prediction of spatial and temporal averages, and does not fully account for all factors that influence regional and national climate variability. This Outlook is relevant only to seasonal time scales and relatively large areas; local variations should be expected. For further information concerning this and other guidance products, users are strongly advised to contact their National Meteorological Services.
Precipitation Outlook  The Outlook for January-March 2000 can also be found at http://iri.columbia.edu/climate/forecast/net_asmt/.

 Maps are given showing expected precipitation probabilities in tercile classes. The maps indicate probabilities that seasonal precipitation will fall into the wettest third of the years (top number), the middlethird of years (middle number) or the driest third of the years (bottom).
An outlook of climatology "C"  (light grey) indicates equal probabilities in each class; i.e., there is no basis for favoring the forecast of any particular category.
Areas marked "D"  (dark grey) experience a pronounced dry season during the forecast period, typically receiving less than 15% of their annual precipitation or less than 5 cm total during this three-month period.
Boundaries between sub-regions should be considered transition zones, and their location considered to be only qualitatively correct.

The following regions of enhanced probabilities of precipitation anomalies are indicated:

P.A) slightly enhanced probabilities of above-normal precipitation over central Libya, north-eastern Niger, and north-western Chad

P.B) slightly enhanced probabilities of below-normal precipitation over part of Iran

P.C) slightly enhanced probabilities of normal precipitation along the south coast of West Africa between Ghana and Equatorial Guinea

P.D) enhanced probabilities of below-normal precipitation over Gabon, Congo, Central African Republic, the northern half of the Democratic Republic of Congo, and extending eastward to about 30E

P.E) slightly enhanced probabilities of normal precipitation over Kenya, southern Ethiopia, most of Uganda, north-eastern Tanzania, and the far south-eastern part of Sudan

P.F) enhanced probabilities of normal precipitation over northern and coastal Angola, most of the southern half of the Democratic Republic of Congo, north-eastern Zambia, most of Tanzania, the northern half of Malawi, and northern Mozambique

P.G) enhanced probabilities of above-normal precipitation over the far northern part of Namibia, southern Angola, most of Zambia, northern Zimbabwe, southern Malawi and central Mozambique

P.H) slightly enhanced probabilities of above-normal precipitation over the west coast of Namibia and South Africa

P.I) slightly enhanced probabilities of below-normal precipitation over the far south-western part of South Africa

P.J) enhanced probabilities of normal precipitation over most of Namibia and South Africa, Botswana, Lesotho, Swaziland, southern Zimbabwe and southern Mozambique

P.K) enhanced probabilities of above-normal precipitation over
Madagascar

P.L) enhanced probabilities of above-normal to normal precipitation over the Seychelles

P.M) slightly enhanced probabilities of normal precipitation over the Mauritius and Reunion

North and Central America

January-March 2000 Precipitation probabilities

The following regions of enhanced probabilities of precipitation anomalies are indicated:

P.A) slightly enhanced probabilities of above-normal precipitation over the Pacific Northwest, covering northern Oregon, Washington, and southern parts of British Columbia and Alberta

P.B) enhanced probabilities of below-normal precipitation in a zone over the southwest United States, extending slightly into northwest Mexico and Baja

P.C) enhanced probabilities of above-normal precipitation over an area extending over the central/north eastern United States, east of about 90E from Tennessee, to southeastern Canada and including the New England States

P.D) enhanced probabilities of below-normal precipitation of the central Atlantic states of the US, from Georgia through southern Maryland

P.E) greatly enhanced probabilities of below-normal precipitation along the Gulf Coast of the United States starting at Texas, and including all of Florida, Cuba, and the Bahamas. There is a slightly enhanced risk of the seasonal precipitation being in the extreme below-normal category over Florida

P.F) enhanced probabilities of below-normal precipitation over the southern tip of Texas down through central eastern Mexico

Temperature OutlookThe Outlook for January-March 2000 can also be found at  http://iri.columbia.edu/forecast/net_asmt.

The temperature map shows expected probabilities that the seasonal temperatures will fall into the warmest third of the years (top number), the middle third of the years, or the coldest third of the years (bottom number).
A qualitative outlook of climatology "C" (light grey) indicates equal probabilities in each class i.e.; there is no basis for favoring the forecast of any particular category.
Boundaries between sub-regions should be considered transition zones, and their location considered to be only qualitatively correct.

The following regions of enhanced probabilities of temperature anomalies are indicated:

T.A) slightly enhanced probabilities of above-normal temperatures over the north coasts of Morocco and Algeria, northern Tunisia, extending northward into southern Europe

T.B) enhanced probabilities of near-normal to above-normal temperatures over most of Morocco, and the northern part of Algeria

T.C) greatly enhanced probabilities of above-normal temperatures over an area extending from southern Mali into northern Sudan and Djibouti, and into the southern part of the Arabian peninsula

T.D) greatly enhanced probabilities of above-normal temperatures over West Africa south of about 10N, extending along the south-west coast to Senegal, and southward to include most of Congo

T.E) greatly enhanced probabilities of above-normal temperatures over Somalia, Djibouti, and the eastern half of Ethiopia

T.F) enhanced probabilities of normal temperatures over Kenya, Uganda, Rwanda, Burundi, Tanzania, northern Zambia and the far northern part of Malawi

T.G) greatly enhanced probabilities of above-normal temperatures over Mozambique, the eastern half of Zimbabwe, south-eastern Zambia, and most of Malawi

T.H) enhanced probabilities of normal temperatures over eastern Angola, western Zambia, Botswana, Lesotho, and most of South Africa

T.I) greatly enhanced-probabilities of above-normal temperatures over Madagascar

January-March 2000 Temperature Probabilities

The following regions of enhanced probabilities of temperature anomalies are indicated:

T.A) greatly enhanced probabilities of below-normal temperatures over a zone extending from the northwest corner of the United States and the entire west coast of Canada eastward to Hudson Bay

T.B) slightly enhanced probabilities of above-normal temperatures over an area extending from the south-western region of the United States, down through the western half of Mexico and extending eastward though the central United States

T.C) enhanced probabilities of above-normal temperatures over the eastern United States

T.D) greatly enhanced probabilities of above-normal temperatures over the eastern half of Mexico, and the gulf coast of the United States, including all of Floria

T.E) enhanced probabilities of below-normal temperatures over Cuba, Jamaica, and the Bahamas

T.F) slightly enhanced probabilities of near-normal to below-normal temperatures over southern Guatemala, Honduras, El Salvador and Nicaragua

• Coupled ocean-atmosphere model predictions of tropical Pacific SST -- particularly heavy weighting has been given to the NOAA /NCEP, Climate Modeling Branch coupled model
• Statistical forecasts of Indian Ocean and Atlantic Ocean sea surface temperature
• The response of Atmospheric global circulation model (GCM) predictions to the present and predicted SST patterns
• Statistical analyses

• Appropriate Regional Climate Outlook Forum consensus guidance.