Africa Drought and Floods Hazards Assessment: May 26, 2004
CCA Guidance for September - October - November at Four Months Lead This week we focus on the outlooks for September - November for east Africa, divided into two areas.
The outlook for Sep-Nov 2004 East Africa rainfall at four months lead show climatology in all areas, except locally over western Uganda, where there is a tilt in the odds favoring above average rainfall (eafSON4.gif).
Northern Horn of Africa
The outlook for Sep-Nov 2004 Northern Horn of Africa rainfall at 4 months lead shows a tilt in the odds favoring above average rainfall locally over southern Sudan and central Ethiopia. Climatology is expected elsewhere (neafSON4.gif).
With respect to the rainfall over Africa, the main body of heavy rainfall has continued to be maintained in the mid-central portion of Africa mainly in an area extending from Gulf of Guinea in the west through northern DRC to southern Sudan and western Ethiopia on the east.
The Gulf of Guinea region received general light rains of about 25 mmm with some scattered areas of 75 mm. Finally, northern Morocco received beneficial rains of about 15 mm with heavier amounts impacting northern Algeria.
The latest report on May 21 from the Food and Agriculture Organization (FAO) of the United Nations, Rome, Italy indicates that intensive ground and aerial control operations continue against hopper bands south of the Atlas Mountains in Morocco, Algeria and Tunisia. Hatching and band formation are expected shortly in northwestern Libya. New swarms continue to form, albeit on a smaller scale, in northern and central Mauritania and the Western Sahara. A few swarms have also formed and dispersed in the Air Mountains, Niger. The situation remains calmer in the Central Region where only small hopper band infestations persist near Dongola, northern Sudan. FAO predicts that swarms will move from Northwest Africa to the Sahel during June and July. There is also some risk that some swarms could reach western Sudan. Additional details can be found at the USAID web site for Assistance for Emergency Locust/Grasshopper Abatement (AELGA) at http://www.aelga.net.
WEEKLY WEATHER HAZARDS ASSESSMENT STATEMENT May 26, 2004 DISCUSSION:
1. Poor performance of the wet season rains over the past several years has resulted in a long term, multi-year drought across the Sool Plateau and the nearby Togdheer Region in northern Somalia. This season, however, has seen an overall good performance of the rains. However no rainfall is expected during the period as the dry season sets in. The next season typically occurs during the month of October.
2. Rainfall totals over the past year were 40 to 65 percent of normal, resulting in long term moisture deficits ranging from 100 to 150 mm over northern Hiraan in Somalia and adjacent parts of southeastern Ethiopia. The deficits are mainly due to the poor performance of last years short rains. Further east, poor Gu rains this year have resulted in March-May rainfall totals that are less than 50 percent of normal across the Galguduud and Mudug regions of central Somalia. This may result in degradation of pastures and reduction in water availability to people and livestock. Dry conditions are expected during the period. The next chance for significant rain will be with the onset of the short rains in October.
3. April rains across the northern belg producing areas of Ethiopia were near to above normal, mainly due to abundant rains early in the month. However, little if any rain has fallen in the vicinity of Dese and Weldiya since April 20th. This has raised concerns over local agriculture. Similar conditions have been observed further west near and just east of Lake Tana where early rains are needed for land preparation efforts prior to the Meher season. Dryness is expected to increase during the period as no significant rainfall is expected. The belg rains have ended prematurely and the next chance for significant rainfall will be with the onset of the Meher rains in June-early July.
4. Multi-seasonal drought has resulted in long term moisture deficits across interior sections of southeastern Kenya and northeastern Tanzania. Short term dryness has increased moisture deficits and has raised concerns over main season crops across most of the area. Dry conditions are expected during the period, which will increase stress on crops and reduce water supplies.
5. March-May rainfall totals so far are only 30 to 60 percent of normal across northeastern Tanzania, much of interior eastern Kenya and the pastoral areas of south-central Ethiopia. This has resulted in deficits of 50 to locally 200+ mm. The long rains typically end during mid-late May, therefore relief is unlikely until the onset of the short rains in October.
6. Along the Kenya coast, a very dry May has resulted in March-May rainfall totals that are only 20-50 percent of normal. In Mombasa , less than 10 mm of rain has fallen over the past 30 days, normal is about 250 mm. In addition, temperatures have been warmer than normal over the past several weeks. May is typically the wettest month of the year along the coast, however heavy rains are also possible during June. Conditions are expected to become more favorable for rainfall along the coast, with rain expected to begin during by mid week. This will help to ease dryness and benefit local agriculture.
AUTHOR: Chester V. Schmitt