Weekly Introduction:
Update of El Niño:
Synopsis:
ENSO-neutral or weak La Niña conditions are likely during the next 6-9 months.
By the end of October, equatorial SST anomalies greater than +0.5ºC were found between Indonesia and 175ºW, while negative anomalies less than –0.5ºC were observed at most locations between 130ºW and the South American coast. The SST departures in the Niño 3, Niño 3.4, and Niño 1+2 regions were negative, while weak positive departures were observed in the Niño 4 region. Collectively, the present oceanic and atmospheric anomalies are consistent with ENSO-neutral conditions in the tropical Pacific.
The spread of the most recent statistical and coupled model forecasts (weak La Niña to weak El Niño) indicates some uncertainty in the outlooks. However, current conditions (stronger-than-average easterly winds over the central equatorial Pacific) and recent observed trends (decreasing SST anomalies throughout the central and eastern equatorial Pacific) do not support the development of El Niño. Rather, they support either a continuation of ENSO-neutral conditions or the development of weak La Niña conditions during the next 6-9 months.
This discussion is a consolidated effort of NOAA and its funded institutions.
Weather Hazards Assessment Graphic:
Weather Hazards Text Explanation:
1. Gu rains in southern Somalia, as well as March – June rains in adjacent Kenya were erratic and early to end during the previous season. This led to widespread areas of hydrological and agricultural problems including poor crop production, dry pasture conditions, and low drinking water levels. As a result, groups of people and their livestock have been relocating to areas of permanent water sources. To further complicate the situation, current seasonal rainfall in much of the affected region in the Horn is delayed by as much as five weeks and is erratic in nature as the season nears its normal peak.
2. Associated with area #1, regions of southern and southeastern Ethiopia, southern Somalia, and much of Kenya are plagued by a similar current-season lack of rainfall. Though much of this area did not experience the severe 2 year drought that was observed to the southeast, the past March – June rains were much lighter than normal. Current seasonal dryness is negatively affecting pastures and agriculture in the region, though some precipitation is expected during the next week.
3. 2004-05 seasonal rainfall totals were between 25-75 percent of normal in parts of southern Malawi, central and southern Mozambique, eastern Zimbabwe and extreme northeastern South Africa. This led to widespread hydrological drought extending into the dry season. Current season rains have been slightly slow to start in the area, though rainfall has increased dramatically during the past two weeks with the passage of a frontal system and associated lingering rainfall activity. A drier regime is forecast to set up over much of the region during the next week, and the area will not see the widespread rainfall that was observed during the past two weekly periods.
4. Seasonal rains in parts of north central Ethiopia and Djibouti were much less than normal, leading to areas localized pastoral dryness in the area. Pasture conditions in and around the Afar region do not show signs of extreme dryness, though some localized problems exist eastward into much of Djibouti. Agriculture to the west, near Weldiya in north central Ethiopia, has been stressed by the erratic late season rainfall, though crops are currently being harvested and any effects are not likely dramatic. Seasonal rainfall has likely ended in the region, though a few periods of light rain may be seen during the next few months, especially to the north along the Red Sea zone.
5. Abnormal dryness continues in much of eastern Tanzania due to seasonal rainfall delays of 3-4 weeks in the area. October rainfall totals were generally near zero for 2005, though long term monthly averages are closer to 25-40 mm. Precipitation is showing signs of increasing though, but seasonal rainfall is late by as much as five weeks throughout the area. Late crop plantings are likely a result of this abnormal dryness, and pasture conditions are negatively affected.
AUTHOR: Timothy B Love
Questions or comments about this product may be directed to Alvin.Miller@noaa.gov or 1-301-763-8000 x7552
FEWS NET is a USAID-funded activity whose purpose is to provide objective information about food security conditions. Its views are not necessarily reflective of those of USAID. The FEWS NET weather hazards assessment process and products include participation by FEWS NET field and home offices, NOAA-CPC, USGS, NASA, and a number of other national and regional organizations in the countries concerned.