Average-to-above average rainfall resulted in favorable agroclimatoligical conditions for crops

• Generally, the 2022 seasonal rainfall has been average to above-average and/or well-distributed in time throughout the region, providing adequate moisture conditions for crop growth and development.
• The 2022 end of season has been normal to slightly late in the Sahelian zone, except in the western portion, where it continues to rain in late October.
• The September-November minor season rainfall in the bimodal zone has been mostly below-average, particularly in southeastern Nigeria and southern Cameroon.  However, moisture conditions are still adequate for crops given the large amount of rainfall normally received in the area.
• Floods have been observed in almost all river basins of the region.

• This portion of the rainfall season is dominated by the southward retreat of the Intertropical Front (ITF).  During the first dekad of October, it was north of its normal position throughout the region and produced generous amount of rainfall in the northern part of the Sahelian zone.  As of the second dekad of October, the ITF remained north of its normal position in its western portion (15W and 1E) and eastern portion (16E-18E), but south of it in its central portion (1E-16E). The slower-than-normal southward ITF retreat over most of the Sahelian zone during the first dekad of October indicates a normal to late end of the 2022 season in the Sahelian zone.
• The seasonal rainfall (Figure 1) has been generally average to above-average and well distributed at the exception of western Niger, northwestern and southern Nigeria, Guinea, Sierra Leone, and southern Cameroon where seasonal rainfall has been below-average.  These rainfall deficits are not expected to negatively affect crop performance, except over western Niger.
  • The large swaths of below-average rainfall areas in the bimodal and parts of the Guinean zone, including Guinea and Sierra Leone, always results in adequate moisture for crops, even under deficit conditions.
  • Most of the Sahelian and Sudanian zone deficit affected areas – with the exception of western Niger, central Mali and southwestern Mauritania – benefited from a regular time distribution (Figure 2 and Figure 3) that often offsets the negative impacts of deficits on crop performance.
• The southern Timbuctoo region in Mali and the southwestern Mauritania border area suffered from rainfall deficits and long dry spells, but only in July at the beginning of the season (Figure 2).  The southwestern part of Niger, however, suffered from below-average rainfall totals and long dry spells in July and September (Figure 2 and Figure 3).  These July conditions led to a late start of season, which is expected to negatively affect yield in an area where most crops are photoperiod sensitive.  The below-average rainfall and long dry spells experienced toward the end of the season in September negatively affected the maturation process, which is also known to result in a significant drop in yield.  Therefore, western Niger – and particularly the northern part of Tillaberi region – is the only area in the region with bad harvest prospects.
• Floods have started in almost all river basins of the Sahelian and Sudanian zone in July while the bimodal zone was entering in its minor dry season.  They continued and got worse in August and spread into the bimodal zone where the minor wet season started in late August and early September.  During the second half of September into early October discharges have exceeded the 5-year return period in Niger River in Mali, Black & White Volta Rivers in Burkina Faso and Ghana, Komadugu and Benue Rivers in Nigeria, and Logone River in Chad.  In Nigeria and Chad, the flood situation continued to deteriorate till mid-October and then waters started to recede.  Relatively important crop damage has been reported, however, the area of damaged crop is but a small percentage of the total cropped area in the affected countries.
• The phytosanitary situation has been generally calm over the region.  The presence of solitary adults of desert locust in very low numbers has been reported in Mauritania and in Niger; few larvae have been also observed northwest of Mauritania; which constitute no threat at all.  Armyworm have been reported causing light damage on maize particularly in Togo and southern Mauritania.  Grasshoppers’ infestation has been also reported in September in some Sahelian countries and particularly in the northern parts Maradi and Zinder regions in Niger.  However, damage was limited to below normal as the plant protection services quickly brought the situation under control.
• According to mid-September PREGEC estimate the regional cereal production is expected to be between 71 and 78 million of MT or between 2% below and &5 above the last 5-years average.  The production of roots and tuber is expected to be 3-9% above the last 5-years average.  However, cash crop production is expected to be below average compared to last year.  The expected decrease is 4-17% is for groundnut, 7-9% for sesame, and 3-8% for cotton.

• The short-term forecasts from NOAA-CPC and subseasonal-to-seasonal (subX and NMME) rainfall forecasts indicate the season in West Africa is coming to an end by mid-November.

Agroclimatic seasonal calendar