METHODS -

This Outlook was prepared using the following procedures and information:

A) Coupled ocean-atmosphere model predictions of tropical Pacific SST covering the forecast period. Particularly heavy weighting has been given to predictions from the coupled model operated by the NOAA National Centers for Environmental Prediction, Climate Modeling Branch. This model suggests a continuation of near-average conditions during the first forecast season. The forecast for near-neutral conditions is consistent with some, but not all, numerical and statistical forecasts of central and eastern Pacific SSTs.

B) Forecasts of the tropical Indian ocean using a statistical model developed by the IRI.

C) Global atmospheric general circulation model (GCM) predictions of the atmospheric response to the present and predicted sea-surface temperature patterns.

D) Other sources of information include NASA's Seasonal to Interannual Prediction Project (GSFC-NASA).

The procedures, models, and data used to derive this Climate Outlook may be somewhat different from those used by the national meteorological services in the region. Thus, this product may differ from the official forecasts issued in those areas. The Climate Outlook for September 2001 - February 2002 is dependent on the accuracy of the SST predictions. For the tropical Pacific, these predictions can be expected to provide useful information, but there is some uncertainty concerning the evolution of SSTs. Spread in global SST predictions is a source of uncertainty in the Outlook provided here. Note that even if perfectly accurate SST forecasts were possible, there would still be uncertainty in the climate forecast due to chaotic internal variability of the atmosphere. These uncertainties are reflected in the probabilities given in the forecast.

It is stressed that 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, and variations within the 3-month season should also be expected. For further information concerning this and other guidance products, users are strongly advised to contact their National Meteorological Services.

This Outlook covers four seasons: September-November 2001, October-December 2001, November-December 2001-January 2002 and December 2001-February 2002. Maps are given showing tercile probabilities of precipitation and temperature. The maps for precipitation indicate the probabilities that the seasonal precipitation will fall into the wettest third of the years (top number), the middle third of the years (middle number), or the driest third of the years (bottom number). The color shading indicates the probability of the most dominant tercile -- that is, the tercile having the highest forecast probability. The color bar alongside the map defines these dominant tercile probability levels. The right side of the color bar shows the colors used for increasingly strong probabilities when the dominant tercile is the above-normal tercile, while the left side shows likewise for the below-normal tercile. The gray color indicates an enhanced probability for the near-normal tercile (nearly always limited to 40%). As before, numbers and their associated histograms show the probabilities of the three terciles. In areas with lots of spatial detail, there may not be sufficient room on the map, to allow histograms for each region. In those cases, some idea of the probabilities may be gained from the color alone. A qualitative outlook of climatology ("C") indicates that there is no basis for favoring any particular category. Areas that are marked by "D" represent regions experiencing their dry season (less than 15% of annual precipitation) and for which less than 5cm of precipitation typically occurs over the season. Otherwise, for example, in the case of Russia in September-November 2001 (Map A), there is a 40% probability that the precipitation will be in the wettest third of the years, a 35% chance it will be in the near-normal third of the years, and a 25% chance that the precipitation will be in the driest third of the years.

Maps of temperature show expected probabilities that the seasonal temperatures will fall into the warmest third of the years, the middle third of the years, or the coldest third of the years (Map A). The numbers for each region on the temperature maps indicate the probabilities of temperatures to fall in each of the three categories, above-, near-, and below-normal.

Boundaries between sub-regions should be considered as transition zones, and their location considered to be only qualitatively correct.

September-October-November 2001:

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

An enhanced probability for below normal precipitation (45%-35%-20%)is forecast for poart of southeastern China, surrounded by more weakly enhanced probabilities for below normal precipitation in additional portions of southeastern China and the northern tip of North Vietnam.

Slightly enhanced probabilities for near normal precipitation (25%-40%-35%) are forecast for the southern Philippines and extreme northern Celebes.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for a small portion of western Siberia.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for the southercn and central Philippines and Palawan.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for the island of Yap, in the Federated States of Micronesia.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for northern Japan , southern Sakhalin of Russia, nd the southern Kuril Islands.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for northern South Korean, North Korea, and a very small portion of adjacent northeast China.

Slightly enhanced probabilities for below normal precipitation (40%-35%-25%) are forecast for extreme southern India, western Sri Lanka and the Maldive Islands.

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

A greatly enhanced probability for above normal temperature (15%-30%-55%) is forecast for westernmost Malaysia and extreme southwest Philippines, surrounded by several levels of more weakly enhanced probabilities for above normal temperature in a vast portion of Indonesia and southern Asia stretching from Afghanistan through India to the tropical Pacific islands. Countries having relatively strongly enhanced probabilities for above normal temperature include the remainder of Malaysia and the Philippines, southeast China and Taiwan, Borneo, the southern and northern ends of Sumatra, the northern Celebes, Nicobar Islands (of India), Irian Jaya of New Guinea, and Palau.

A greatly enhanced probability for below normal temperature (50%-30%-20%)is forecast for the extreme western Aleutian Islands of Alaska and the Commander Islands off the east coast of Kamchatka, Russia, surrounded by more weakly enhanced probabilities for below normal temperature in Kamchatka, the Kuril Islands and part of the Koryak Range of eastern Russia.

Slightly enhanced probabilities for near normal temperature (35%-40%-25%) are forecast for the southern Kuril Islands.

An enhanced probability for above normal temperature (20%-35%-45%) is forecast for Sri Lanka, as well as in the Maldives, surrounded by more weakly enhanced probabilities for above normal temperature in adjacent Indian Ocean waters.

An enhanced probability for above normal temperature (25%-30%-45%) is forecast for eastern Russia along the Sea of Okhotsk, surrounded by more weakly enhanced probabilities for above normal temperature to the northwest, also in eastern Russia.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for portions of mainly southern Japan.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for part of Iran.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for Hainan, of southern China.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for the southern tip of India.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for Cambodia and South Viet Nam.

Slightly enhanced probabilities for above normal temperature (30%-30%-40%)are forecast for west-central Siberia of Russia.

Slightly enhanced probabilities for above normal temperature (30%-30%-40%)are forecast for the part of Russia near Lake Baikal, and ajacent northern Mongolia.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for the western tip of China.

October-November-December 2001:

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

An enhanced probability for below normal precipitation (45%-35%-20%)is forecast for interior southeastern China, surrounded by more weakly enhanced probabilities for below normal precipitation in an expanded portion of southeastern China, as well as Taiwan, northern Myanmar and northern Vietnam.

An enhanced probability for above normal precipitation (20%-35%-45%) is forecast for Yap in the Federated States of Micronesia.

Slightly enhanced probabilities for near normal precipitation (30%-40%-30%)are forecast for most of the Philippines and extreme north Malaysia.

Slightly enhanced probabilities for above normal precipitation (30%-30%-40%)are forecast for parts of Pakistan and Afghanistan.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for a part of Siberia, Russia.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for South Korea and southern Japan.

Slightly enhanced probabilities for below normal precipitation (40%-35%-25%) are forecast for a small part of eastern Siberia, Russia.

Slightly enhanced probabilities for below normal precipitation (40%-35%-25%) are forecast for north-central and western India.

Slightly enhanced probabilities for below normal precipitation (40%-35%-25%) are forecast for western Sri Lanka and extreme southern India.

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

An enhanced probability for above normal temperature (20%-35%-45%) is forecast for northern China along the border of Mongolia, surrounded by more weakly enhanced probabilities for above normal temperature in additional portions of China and Mongolia.

Slightly enhanced probabilities for near normal temperature (30%-40%-30% and 35%-40%-25%) are forecast for the northern half of Kamchatka, Russia.

Slightly enhanced probabilities for near normal temperature (30%-40%-30%)are forecast for much of Afghanistan, a small part of southwestern Russia, and western Pakistan.

Slightly enhanced probabilities for near normal temperature (30%-40%-30% and 25%-40%-35%) are forecast for most of Japan.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for southern India and Sri Lanka.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for part of South Korea.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for a small part of southeast Russia, along the Tatar Strait.

Slightly enhanced probabilities for near normal temperature (25%-40%-35% and 30%-40%-30%)are forecast for parts of Laos, Cambodia and Vietnam.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for part of southwestern Myanmar.

Slightly enhanced probabilities for near normal temperature (30%-40%-30% and 25%-40%-35%) are forecast for extensive portions of southern Asia and Indonesia, most prevalently in the vicinities of Sumatra, Malaysia, Borneo, eastern Java, Timor, and western Philippines.

Slightly enhanced probabilities for above normal temperature (30%-30%-40%)are forecast for a part of northern Siberia along the coast of the Arctic Ocean.

Slightly enhanced probabilities for above normal temperature (30%-30%-40%)are forecast for the extreme eastern portion of Russia, bordering the Arctic Ocean and Bering Strait.

Slightly enhanced probabilities for above normal temperature (30%-30%-40% and 25%-35%-40%)are forecast for extreme northeastern China and adjacent southern Russia.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for west-central Siberia, Russia.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for part of intermediate southern Myanmar and part of Thailand.

A greatly enhanced probability for above normal temperature (20%-30%-50%)is forecast for Guam, (U.S.), and Yap, (Federated States of Micronesia).

Slightly enhanced probabilities for below normal temperature (40%-35%-25%) are forecast for southern Kamchatka, Russia, the western Aleutians (Alaska), and the Kuril Islands of Russia.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for the southern Philippines.

November-December 2001-January 2002:

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

An enhanced probability for above normal temperature (20%-35%-45%) is forecast for far eastern Russia, northeast of Kamchatka, surrounded by more weakly enhanced probabilities for above normal temperature in additional areas in the same region.

An enhanced probability for below normal temperature (45%-35%-20%)is forecast for the most of the Kuril Islands of Russia, surrounded by more weakly enhanced probabilities for below normal temperature in southern Kamchatka and the southern part of the Kuril Islands.

An enhanced probability for below normal precipitation (45%-35%-20%)is forecast for southeast China and Taiwan, surrounded by more weakly enhanced probabilities for below normal precipitation in an additional portion of southeastern and eastern China and southern Japan.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for western Mongolia.

Slightly enhanced probabilities for below normal precipitation (40%-35%-25%) are forecast for southern India and the Maldive Islands.

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

Slightly enhanced probabilities for near normal temperature (30%-40%-30% and 35%-40%-25%) are forecast for Taiwan and the northern Philippines.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for central and southern Japan, and South Korea.

Slightly enhanced probabilities for near normal temperature (35%-40%-25%) are forecast for northern Japan.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for southern Iran.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for much of the southern third of India, and Sri Lanka.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for parts of Laos, VietNam and Cambodia.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for southern Thailand and the Nicobar Islands.

Slightly enhanced probabilities for above normal temperature (30%-30%-40%)are forecast for northwestern Siberia, Russia.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for southern Russia, adjacent northwestern China and western Mongolia.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for western China and extyreme northeastern India.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for southern Pakistan and western India.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for the southern Philippines.

Slightly enhanced probabilities for below normal temperature (40%-35%-25%) are forecast for Kamchatka, Russia

Slightly enhanced probabilities for below normal and near normal temperature (40%-40%-20%)are forecast for the northern Philippines.

December 2001-January-February 2002:

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

A greatly enhanced probability for below normal precipitation (50%-25%-25%) is forecast for central and southern Japan, surrounded by more weakly enhanced probabilities for below normal precipitation in more of northern Japan, the Ryukyu Islands, part of South Korea, and a portion of eastern China.

An enhanced probability for below normal precipitation (45%-40%-15%) is forecast for the southwestern Philippines, surrounded by more weakly enhanced probabilities for below normal precipitation in much of the remainder of the Philippines.

Slightly enhanced probabilities for near normal precipitation (35%-40%-25%) are forecast for the southeastern Philippines.

Slightly enhanced probabilities for near normal precipitation (35%-40%-25%) are forecast for Brunei part of Malaysia, and the southwestern Philippines.

Slightly enhanced probabilities for above normal precipitation (30%-30%-40%)are forecast for part of the New Siberian Islands, north of Siberia in the Arctic Ocean.

Slightly enhanced probabilities for above normal precipitation (30%-30%-40%)are forecast for southern Iran.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for part of Afghanistan, and very small parts of southern Russia and Pakistan.

Slightly enhanced probabilities for above normal precipitation (25%-35%-40%)are forecast for Yap Island, in the Federated States of Micronesia.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for a portion of Siberia, Russia.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for eastern Russia, including Sakhalin and the Tatar Strait.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for southern Myanmar and parts of Thailand and Laos.

Slightly enhanced probabilities for below normal precipitation (40%-30%-30%)are forecast for Sri Lanka, the southern tip of India, and the Maldive Islands.

Slightly enhanced probabilities for below normal precipitation (40%-35%-25%) are forecast for southern Thailand and northern Malaysia.

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

An enhanced probability for above normal temperature (25%-30%-45%) is forecast for a part of eastern and northeastern China, all of North Korea, and part of south Korea, surrounded by more weakly enhanced probabilities for above normal temperature in additional portions of central and eastern China, most of Mongolia, and parts of Russia.

An enhanced probability for below normal temperature (45%-35%-20%)is forecast for the northern Philippines, surrounded by more weakly enhanced probabilities for below normal temperature in much of the remainder of the Philippines, northwestern Malaysia, and Taiwan.

An enhanced probability for above normal temperature (20%-35%-45%) is forecast for southern Myanmar, surrounded by more weakly enhanced probabilities for above normal temperature in most of the remainder of Myanmar, western Thailand, extreme eastern India and extreme southern China.

An enhanced probability for below normal temperature (45%-35%-20%)is forecast for eastern Russia near the Sea of Okhotsk, as well as for a separate but associated region over part of Kamchatka and the Kuril Islands, Russia. Surrounding and connecting both of these regions are more weakly enhanced probabilities for below normal temperature, including northern Japan and additional portions of eastern Russia.

Slightly enhanced probabilities for near normal temperature (35%-40%-25%) are forecast for extreme southern China, and parts of Laos, VietNam, Cambodia, and Thailand.

Slightly enhanced probabilities for near normal temperature (35%-40%-25%) are forecast for the southern Philippines, the northern Celebes, Brunei, and parts of Malaysia and Borneo.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for part of Nepal, and part of eastern India.

Slightly enhanced probabilities for near normal temperature (25%-40%-35%) are forecast for southwestern India.

Slightly enhanced probabilities for above normal temperature (30%-30%-40% and 25%-35%-40%)are forecast for western India, southern Pakistan and extreme southern Afghanistan.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for far eastern Russia, northeast of Kamchatka.

Slightly enhanced probabilities for above normal temperature (25%-35%-40%)are forecast for southern Russia, to the northwest of northwestern China.

Slightly enhanced probabilities for below normal and near normal temperature (40%-40%-20%)are forecast for the southern part of south Vietnam and extreme southern Cambodia.

OBSERVED CLIMATOLOGY DATA for Sep-Oct-Nov, Oct-Nov-Dec, Nov-Dec-Jan and Dec-Jan-Feb

CLIMATOLOGICAL AVERAGE: Temperature Precipitation

TERCILE THRESHOLDS (33%-ile & 67%-ile): Temperature Precipitation

EXTREME THRESHOLDS (15%-ile & 85 %-ile): Temperature Precipitation

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