Seasonal Rainfall Outlook for June to August 2019

The Ministry of Agriculture, Animal Industry and Fisheries collaborates with the Uganda Meteorological Authority (UNMA) through a focal office to provide weather and climate-related updates to farmers through the extension system and communication platforms of the Ministry.

Below is an excerpt of the Rainfall Outlook from UNMA signed off by the UNMA Executive Director Mr. Festus Luboyera.

The June, July and August forecast period is part of the dry season over most parts of South western, Central, Lake Victoria basin and parts of Eastern region but a continuation of rain season for much of Northern Uganda. In Southern sector, it marks the end of the first rainfall season and is generally crops harvesting season.

At the 52nd Climate Outlook Forum for the Greater Horn of Africa held in Addis Ababa in Ethiopia, from 28th – 29th May 2019, the National, Regional and International Climate Scientists reviewed the state of the global climate system and its implications on the seasonal rainfall over the Eastern Africa region. It was observed that the major physical conditions likely to influence the weather conditions over Uganda and the rest of the east African region for the forecast period of June to August 2019 are as follows:-

  1. The Indian Ocean Dipole (IOD) that significantly influences the regional climate currently in a neutral phase expected to slightly strengthen during the forecast period;
  2. The slightly positive SST anomalies currently present in the Tropical Pacific are expected to remain warmer than normal through the forecast period which calls for close monitoring;
  3. The influence of regional atmospheric circulation patterns, topographical features and large inland water bodies.

Based on the above considerations as well as details of the climatology of Uganda and scientific tools for climate analysis, Uganda National Meteorological Authority (UNMA) under Ministry of Water and Environment has downscaled the regional forecast and come up with the following detailed forecast:-

Overall, there is an increased likelihood of normal rainfall tending to below normal rainfall over the north western, parts of Western and South western Uganda, while parts of Lake Victoria and Eastern region is likely to experience above normal rainfall. The rest of the country is expected to experience Near Normal dry conditions punctuated with occasional light rains as shown by the map below:

Figure1: JJA 2019 climate Outlook.

The Breakdown of the Forecast for each region

WESTERN REGION

Central Western (Bundibugyo, Ntoroko, Kabarole, Kyenjojo, Kyegegwa, Kamwenge, Masindi, Buliisa, Hoima, Kakumiro, and Kibaale) districts

This region is experiencing moderate rainfall characterized by short dry spells. This condition is expected to persist up to around late June / early July when the dry conditions are expected to begin and continue up to the end of season. Overall, near normal to below normal rainfall (average to suppressed rainfall) is expected to prevail over most parts of the region.

South Western (Kasese, Kabale, Kisoro, Rukungiri, Kanungu, Ntungamo, Mbarara, Kiruhura, Isingiro, Ibanda, Bushenyi, Buhweju, Mitooma, Sheema and Rubirizi) districts

The region is receiving intermittent light rains which are likely to persist up to early-June. Thereafter, dry conditions are expected to set in and continue up to last week of July when isolated outbreak of light showers is expected to set in fast week of August, followed by dry spell punctuated with light rains upto the end of the season. Overall, below normal (suppressed rainfall/dry conditions) is expected over most parts of the region.

LAKE VICTORIA BASIN AND CENTRAL REGION

Northern and Southern parts of Central (Nakasongola, Luwero, Kyankwanzi, Nakaseke Kiboga, Mubende, Kasanda, Sembabule, Lwengo, Lyantonde, and Rakai) districts.

The rains being experienced over this region signify the onset of JJA & they are expected to continue up to the end of June to early July when dry conditions punctuated with light rains are expected to set in and continue until end of season. Overall, there are high chances of near normal (average) rainfall with tendency to above normal rainfall over most parts of the region.

Eastern parts of Central (Mukono, Buikwe, Kayunga, Buvuma) districts.

This region is experiencing rains which are expected to continue up to late June. Intermittent rains punctuated with dry spells are expected around July and continue up to the end of the forecast period. Overall, above normal rainfall with a tendency to below normal (suppressed) rainfall is over most parts of the region.

Central and Western Lake Victoria Basin (Kalangala, Kampala, Wakiso, Masaka, Mpigi, Butambala, Kalungu, Bukomansimbi, Gomba, and Mityana) districts

The region is experiencing occasional showers and thunderstorms, which are expected to continue up to late June / early July. Thereafter, relatively dry conditions are expected to set in and persist up to the end of July. However, some parts of  Kampala, Wakiso and Mpigi are expected to continue experiencing intermitted rains until the end of forecast period. Overall near normal (average) rainfall with tendency towards above normal rainfall is expected during this season.

Eastern Lake Victoria Basin: (Jinja, Bugiri, Busia, Mayuge, Namayingo and Tororo) districts.

The region is currently experiencing some showers and thunderstorms that are likely to continue up to end of June / early July when the dry conditions punctuated with intermitted rains are expected to set in and continue up to the end of forecast period. Overall, near normal (average) rainfallwithtendency to above normal rainfall is expected.

EASTERN REGION

South Eastern: (Kamuli, Iganga, Luuka, Namutumba, Buyende, Kaliro, and Butaleja) districts

The rains which are being experienced over this region are expected to continue up to mid June when the dry conditions are expected to begin and prevail up to the end of June, thereafter, occasional outbreaks of showers and thunderstorms are expected to set in and prevail up to the end of the forecast period. Overall, there are high chances of near normal (average) rainfall with tendency to above normal rainfall conditions over this region.

Eastern Central: (Pallisa, Budaka, Kibuku, Mbale, Sironko, Manafwa, Bududa, Bulambuli, Kapchorwa, Kween, Bukwo, Bukedea, Kumi, Kaberamaido, Serere and Soroti) districts.

The rains which are being experienced over this region are expected to continue up to mid June when the dry conditions are expected to begin and prevail up to the end of June, thereafter, occasional outbreaks of showers and thunderstorms are expected to set in and prevail up to the end of the forecast period. Overall, there are high chances of above normal rainfall over this season.

North Eastern:  (Amuria, Katakwi, Moroto, Kotido, Nakapiripirit, Abim, Napak, Amudat, and Kaabong) districts

The region is experiencing occasional showers and thunderstorms punctuated with some dry spells which are expected to continue up to end of June, when a reduction in the rainfall is likely to be experienced until end of the season. Overall, below normal rainfall is expected in northern parts of Karamoja, whereas near normal rainfall is expected over the southern parts Karamoja region during this season.

NORTHERN REGION

North Western (Moyo, Yumbe,  Adjumani, Arua,  Maracha, Zombo, Nebbi, Koboko) districts

The region is experiencing intermittent seasonal rains punctuated with dry spells which are expected to continue up to the end of the season. Overall, near normal (average) rainfall with tendency below normal rainfall is expected over this region.

Eastern Northern Parts: (Lira, Kitgum, Agago, Lamwo, Otuke, Pader, Alebtong, Kole, and Dokolo ) districts

The region has been experiencing showers punctuated with dry conditions since mid-May which is expected to continue till mid-June when the rains are expected to reduce till mid-July with a dry spell setting in. The dry condition is expected to persist up to mid-August when the rains pick again until end of the season. Overall, there are high chances for this region receiving below normal with slight tendency to near normal (average) rainfall.

Central Northern Parts: (Gulu, Apac, Pader, Nwoya, Amuru, Oyam and Kiryandongo) districts

The period June to August (JJA) is normally a continuation of rainy season for March to May season over this region. Currently, the region is experiencing wet conditions which are expected to continue up to late June when a reduction in the rains is expected to set in. Thereafter, showers punctuated with dry spells are expected to continue up to the end of the season. Overall, there are high chances for this region receiving below normal with slight tendency to above normal (average) rains over the JJA forecast period.

ACCURACY          

This forecast is up to 75% accurate.  It is supported by useful forecast guidance inputs drawn from a wide range of sources including the World Meteorological Organization’s Global Producing Centres’ (WMO GPCs). These inputs were combined into a regional consensus forecast using objectively deterministic and probabilistic modelling alongside expert analysis and interpretation to obtain the rainfall forecast for this June-July-August (JJA) season.

UNMA will continue to monitor the evolution of relevant weather systems particularly the seas surface temperatures in Indian and pacific oceans (IOD, El Niño/Laniña event) and accordingly issue appropriate updates and advisories to the users.