October 11-31 2000 - During October 21-31, 2000, the ITCZ in West Africa (10 degrees W to 10 degrees E) retreated southward 2.4 degrees latitude to 12.7 N, which is near the 1979-98 mean. Over East Africa (20 to 35 degrees east longitude), the ITCZ retreated 1.2 degrees south to 10.3 N. This is 1.2 degrees south of the 1988-99 mean of 11.5 N. The ITCZ was near normal over Mauritania, Mali, and Burkina Faso, and south of normal from Nigeria to western and central Sudan. During June-September 2000, the most important months for the Sahel rainy season, the ITCZ mean location of 17.8 N in West Africa was near the 1979-98 mean but 0.4 degrees south of the 1999 mean. The eastern Africa ITCZ mean position for June- September 2000 was the farthest south since 1990. The is the last report for the season. Monitoring for next season's ITCZ will begin in April 2001.

October 1-10 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E) retreated southward 1.1 degrees latitude to 15.4 N, which is close to the 1979-98 mean of 15.5 N. Over East Africa (20 to 35 degrees east longitude), the ITCZ advanced 0.2 degrees northward to 14.3 N. This is near the 1988-99 mean of 14.1 N. The ITCZ was south of normal over Mauritania, Mali, and Chad, and north of normal in eastern Sudan.

September 21-30 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E) retreated southward 1.5 degrees latitude to 16.5 N, which equals the 1979-98 mean. The June-September 2000 mean location of 17.8 N also equals the 1979-98 mean, but is 0.4 degrees south of last year's position. Over East Africa (20 to 35 degrees east longitude), the ITCZ retreated 1.8 degrees southward to 14.1 N. This is the lowest latitude for this time of year since records began in 1988, and is 1.0 degrees south of the 1988-99 mean. The June-September mean of 15.2 N is 0.4 degrees south of the 1988-99 mean. As the ITCZ movement implies, rainfall amounts decreased sharply in the Sahel as the rains moved southward in late September. The ITCZ was north of normal over Mauritania and south of normal from eastern Mali to Sudan. The overall season appears to be drier than last year across the region and drier than the long-term mean.

September 11-20 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E) advanced northward 0.6 degrees latitude to 18.0 N, 0.5 degrees north of the 1979-98 mean position of 17.5 N. The ITCZ typically retreats southward during this time of year, so the move northward was rather unusual. This was the largest advance northward for this time of year since the ITCZ moved 0.7 degrees north on September 11-20, 1983. Over East Africa (20 to 35 degrees east longitude), the ITCZ also advanced 0.6 degrees north. Its position of 15.9 N was 0.2 degrees north of the 1988-99 mean. This was the first time the ITCZ had been north of normal following four consecutive periods south of normal. Rainfall amounts tended to be above normal over West Africa. Reported rainfall, however, was mostly below normal in Sudan, despite the ITCZ averaging slightly north of normal. The ITCZ actually dipped sharply southward after September 14 and was generally south of normal during September 15-20.

September 1-10 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E) dropped sharply southward to 17.4 degrees north latitude, 1.3 degrees latitude south of the August 21-31 position and 0.8 degrees south of the 1979-98 mean position of 18.2 N. This is the farthest south location for this period since 1984, when it dipped to 16.6N. Over East Africa (20 to 35 degrees east longitude), the ITCZ retreated southward 0.5 degrees latitude to 15.3 N, which is 0.7 degrees south of the 1988-99 mean. This was the fourth consecutive period that the ITCZ was south of normal in the east and the second week it was south of normal in the west. As a consequence, rainfall amounts were below normal and temperatures above normal from Senegal to Sudan. The rainy season may have ended prematurely in the northern-most crop areas from Niger to western Sudan.

August 21-31 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E) retreated southward 0.7 degrees latitude. Its mean position of 18.7 degrees north was slightly south of the 1979-98 mean position of 19.0 N. Though the ITCZ has peaked and started its seasonal migration southward, there was little evidence of the rain band sliding southward across West Africa. The overall rainy season has been generally favorable across West Africa, with the rains mostly near or north of their long-term mean location since April. To the east, however, rainfall appeared to be much lighter in central Sudan, with temperatures above normal, reflecting a more significant shift in the ITCZ southward in this part of Africa. Over East Africa (20 to 35 degrees east longitude), the ITCZ retreated southward 0.8 degrees latitude to 15.8 N, which is 1.0 degrees south of the 1988-99 mean of 16.3 N. This was the third consecutive period that the ITCZ was south of normal in the east and, as a consequence, rains have continued erratic and spotty in Sudan while temperatures have been above normal. The ITCZ was south of normal mainly from eastern Niger to western Sudan.

August 11-20 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E)advanced northward 1.2 degrees latitude. Its mean position of 19.4 degrees north was near the 1979-98 mean position of 19.3 N. As a result, the seasonal rain band generally moved northward, bringing more rain to the Sahel and less to the south, expanding the "little dry season" from Liberia to Nigeria. Over East Africa (20 to 35 degrees east longitude), the ITCZ advanced 0.4 degrees latitude north to 16.6 N, which is 0.7 degrees south of the 1988-99 mean of 17.3 N. This was the second consecutive period that the ITCZ was south of normal in the east and, as a consequence, rains have been spotty in Sudan. The ITCZ was south of normal from eastern Niger to western Sudan.

August 1-10 2000 - The ITCZ in West Africa (10 degrees W to 10 degrees E) retreated southward 1.3 degrees latitude. Its mean position of 18.2 degrees north was 0.9 degrees south of the 1979-98 mean position. The ITCZ typically progresses north during this time of the year, so the retreat southward is unusual. The implication is that the seasonal rains have stalled, and the rainfall analysis for August 1-10 does indeed indicate that the leading edge of the rains in the Sahel did not advance northward, and even dropped slightly southward in places. Over East Africa (20 to 35 degrees east longitude), the ITCZ retreated 0.2 degrees latitude south to 16.2 N, which is 0.9 degrees south of the 1988-99 mean of 17.1 N. The ITCZ was south of normal throughout the region, and especially so over Chad, eastern Niger, and western Sudan.

July 21-31 2000 - During July 21-31, 2000, the ITCZ in West Africa (10 degrees W to 10 degrees E) advanced northward 0.2 degrees latitude. Its mean position of 19.5 degrees north was 0.6 degrees north of the 1979-98 mean position. The ITCZ has been north of its long-term mean position for the past three periods. This suggests the rainy season is advancing ahead of schedule over much of West Africa. Over East Africa (20 to 35 degrees east longitude), the ITCZ advanced 0.5 degrees latitude north to 16.4 N, which is at the 1988-99 mean of 16.4 N. The ITCZ was north of normal over eastern Mauritania and Mali, but south of normal over Chad and western Sudan.

July 11-20 2000 - During July 11-20, 2000, the ITCZ surged northward 1.5 degrees latitude in West Africa (10 degrees W to 10 degrees E). Its mean position of 19.3 degrees north was 1.0 degrees north of the 1979-98 mean position. The ITCZ had been close to its long-term mean position for most of this season until the current period's advance to a position north of normal. This suggests the rainy season is advancing ahead of schedule over much of West Africa. Over East Africa (20 to 35 degrees east longitude), the ITCZ advanced 1.1 degrees latitude north to 15.9 N, which is near the 1988-99 mean of 16.0 N. The ITCZ was north of normal from eastern Mauritania to Niger and near to slightly south of normal in Sudan.

July 1-10 2000 - During July 1-10, 2000, the ITCZ/ITD over West Africa leapt northward by 1.4 degrees latitude, averaging 17.8 degrees N, which is 0.3 degrees north of its long-term mean position. Over East Africa, the ITCZ/ITD advanced 0.8 degrees latitude, averaging 14.N, or 0.5 degrees south of its long-term mean position. Since June 1, the ITCZ has average precisely normal in the west, and 0.5 degrees south of normal in the east.

June 21-30 2000 - During June 21-30, 2000, the ITCZ/ITD over West Africa remained near its previous location, averaging 16.4 degrees latitude north, or 0.1 degrees south of the June 11-20 location. This is 0.6 degrees south of the 20-year mean location. It is rather unusual for the ITCZ/ITD not to migrate northward during this time of year, and implies that the seasonal rains are no longer advancing northward on schedule across the Sahel. Likewise, the ITCZ/ITD made little progress in East Africa, averaging 14.0N vs 13.9N during June 11-20 and the long-term mean of 14.6N.

June 11-20 2000 - During June 11-20, 2000 the ITD/ITCZ advanced 0.5 degrees north to 16.5 degrees latitude north, which was 0.1 degree north of the long-term mean position. Over West Africa, the ITD has been "abnormally normal" this season, with the location within 0.2 degrees of the long-term mean every 10-day period starting April 21-30. This suggests the rainy season has advanced at an average pace. In East Africa, the ITD advanced 0.9 degrees north to 13.9 N. This was 0.2 degrees south of the long-term mean.

June 1-10 2000 - During June 1-10, 2000, the ITD/ITF advanced 0.7 degrees latitude north to 16.0 N over West Africa but retreated 0.7 degrees lat to 13.0 N in East Africa. In West Africa, the location was the same as the long-term average, indicating that the seasonal rains appear to be advancing on schedule. In East Africa, the 10-day position was 0.7 degrees south of the long-term mean.

May 21-31 2000 - The ITD/ITCZ continued its seasonal march northward during May 21-31, with the mean position near 15.3 N in West Africa and 13.7 N in East Africa. In the west, this was near the long-term mean of 15.4 N, and 0.6 degrees north of its position during May 11-20, 2000. In the east, the ITD was located 0.7 degrees north of its long-term mean location and 0.7 degrees north of the May 11-20 location.

May 11-20 2000 - The ITD/ITCZ advanced 1.0 degrees northward in West Africa to 14.7 degrees north, putting it close to the long-term mean of 14.6 N. In East Africa, the ITD advanced sharply northward by 2.2 degrees, averaging 13.0 N, which is 0.7 degrees north of normal.

May 1-10 2000 - During May 1-10, the ITD/ITCZ progressed northward 0.5 degrees latitude to 13.7 degrees N over West Africa and 0.5 degrees to 10.8 N over East Africa. For the west, this was near the long-term mean of 13.9 N, but for the east, the position was well south of the long-term mean of 12.1 N and the farthest south for this time of year of record (since 1989, 1994 and 1997 missing). The implication is that the rainy season is progressing normally in the west, but is struggling in the east, where the ITD/ITCZ has been well south of normal during the past two 10-day periods.

April 21-30 2000 - The ITD/ITCZ changed little during April 21-31 across West Africa, its average position near 13.2 degrees north lat. This is at the long-term mean and just 0.1 degrees north of the previous period's location. To the east, the ITD actually retreated southward, averaging 10.2 degrees north latitude. This was 1.5 degrees south of the long-term mean and 1.6 degrees south of the April 11-20 position. It is not unusual for the ITD to retreat short distances during its progress northward during April-July, but it is rare for it to regress more than 1 degree latitude.

April 11-20 2000 - The ITD/ITCZ advanced significantly northward this period. Over West Africa, its average position of 13.1 degrees north was 0.6 degrees north of its previous location and 0.8 degrees north of the long-term mean. In East Africa, the ITD's location at 11.9 degrees north was 2.9 degrees north of its previous location and 1.0 degrees north of the long-term mean.

April 1-10 2000 - During April 1-10, 2000, the ITD/ITCZ was located near 12.5 degrees N latitude over West Africa (10 degrees W to 10 degrees E) and 9.0 degrees N latitude in East Africa (20 degrees E to 35 degrees E). Over West Africa, the daily position varied from 11.0 N on the 6th to 13.6 N on the 4th. The mean position of 12.5 N in the west was 1.2 degrees north of the 20-year (1979-98) mean. This was the farthest north location for April 1-10 since monitoring began in 1979. The mean position of 9.0 N in the east was 0.2 degrees north of the long-term (1989-98) mean.