vf-tropicom Location of Rains Across West Africa

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The Calculated Rain Line Location Across the Season

Rainline location


The Intertropical Discontinuity/Intertropical Front

From the African Desk, Climate Prediction Center, NOAA

NOTE: The ITCZ for March and for November-December is an experimental product.

December 21-31 2003 - During the final ten days, the African portion of the Intertropical Convergence Zone moved significantly southward , especially in eastern regions near Uganda, DRC, Congo, and Gabon. In extreme eastern areas, the ITCZ is becoming more diffuse as the weeks pass, as convergence into areas of southern Africa is more apparent. Rainfall in Sahelian regions north of the Gulf of Guinea was very light during the period, as was precipitation in CAR, southern Sudan, and Uganda. In the west (10W-10E) the ITCZ continued its southward movement. Its latest average location here is 5.2N as opposed to 7.3N from the previous period. In the east (20-35E) the ITCZ rocketed southward almost five degrees from the last period. The average location is now 1.7N, as opposed to 6.0N during December 11-20. It should be noted that with the shift in convergence patterns comes difficulty in distinguishing the ITCZ with the current method, and thus positional information will be suspended until March or April 2004. Thanks for your patience.

December 11-20 2003 - The African portion of the ITCZ was located near 6.5 degrees north latitude, or around 0.3 degrees north from its position during the first ten days of December. The strong northerly winds responsible for the rapid southward movement of the ITCZ during Dec 1-10 moderated for this period and allowed the convergence zone to move slightly back northward. Examining precipitation associated with both periods, a substantial decrease was observed during the recent ten days throughout much of the Greater Horn of Africa, though rainfall was slightly heavier in parts of northern DRC and Uganda. This was likely due to the northward movement of the ITCZ near these longitudes. Little overall movement is evident in the western ITCZ region, though there was movement northward in the east.

December 1-10 2003 - The African ITCZ was located on average near 6.2 degrees north latitude. This reflects a southward movement of approximately 2.4 degrees to the south from the previous ten day period, and a decrease in ten day accumulated precipitation in Guinea, southern Nigeria, CAR, northern DRC, and southern Sudan. Although areas of the Greater Horn of Africa saw markedly increased rainfall, the ITCZ does not explain it. Rather, stronger than normal southeasterly winds from the Indian Ocean led to increased moisture transport into the region. Examining the western region (10W-10E), the position of the ITCZ was near 7.5N, as opposed to near 8.9N during the previous period. From 20-35E, the location averaged around 4.8N, a dramatic almost four degrees to the south from its November 21 -30 position! Very strong northerly winds blowing from Egypt and Sudan helped to push the convergence zone to the south.

November 21-30 2003 - The African portion of the Intertropical Convergence Zone was located near 8.8 degrees north latitude, or around 2.0 degrees south from its position during the second ten days of November. Over the past 10 days, the ITCZ has shown significant movement southward, especially over central portions of the continent. Over Nigeria, Cameroon and Chad the ITCZ migrated nearly 3 degrees southward. The eastern-half showed some movement to the south of about 1.3 degrees, while the western half had a southward migration. Heavier rain showers have now moved south of the Gulf of Guinea coast in western Africa, while in the east, most of the rain is confined to southern Sudan and Ethiopia. The generally large southward movement of the ITCZ is expected to continue over the next month.

November 11-20 2003 - The African portion of the Intertropical Convergence Zone was located near 10.7 degrees north latitude, or around 1.0 degree south from its position during the first ten days of November. During the current period the most significant movement in the ITCZ was seen in the west, which is contradictory to the past several weeks. The western side has shown movement of nearly 2 degrees southward over the past 10 days. The eastern side showed limited movement south as only the eastern-most two data points or longitude lines showed a migration of about 0.3 degrees south. Central regions were difficult to discern as data was limited in these regions.

November 1-10 2003 - While central and eastern longitudes saw a pronounced southward movement of the ITCZ, the region from western Mali into southern Senegal and Guinea noted little movement. This lack of change in the western region is related to the anomalous precipitation seen locally in the area, though rains did decrease throughout much of Mauritania. The current position is a degree or two north of normal. This contrasts with the eastern region depicted, where the latest position appears to be much closer to normal.

October 21-31 2003 - The ITCZ continued its southward movement, though its northward bias from the 1998-2002 climatological mean increased. Overall, the ITCZ was located near 13.1 degrees north latitude, compared with a normal position near 12.5 north. This compares to the previous position, collocated with the mean, around to 14.6 degrees north. Responsible for the northward bias was a stronger-than-normal low pressure region in western Africa which brought strong southerly winds to the area and pushed the area of convergence slightly north from October 24-28. The effects of this northward bias of the ITCZ could be seen in southern Mali and Burkina, where heavier than normal rainfall was noted. Further north, into areas of western Algeria, northwestern Mauritania, and West Sahara, moderate showers fell, also in relation to the meteorological factors governing the ITCZ last period. From 10 degrees west to 10 degrees east longitude the 2003 ITCZ southward progression has followed the 1979-2002 normals closely, except the deviation during the last ten days of October. From 20-35 degrees east longitude, while this region was near normal for the period, a slight northward bias allowed some abnormal rainfall to be seen over parts of northeastern Sudan.

October 11-20 2003 - The Intertropical Convergence Zone over Africa was located near 14.2 degrees north latitude, or around 0.3 degrees north of the 1988-2002 normal. The rate of descent increased somewhat for this period as the ITCZ moved around 1.0 degree southward over the past 10 days. In the Sahel, the ITCZ has shown the most southward movement, as during the last period the northern extent was almost 17 degrees north, while during this period it moved to around 15 degrees north or a 2 degree southward movement. The 10-day rainfall totals seem to correlate with this sharp movement as the heaviest rains are now confined to the immediate coastal areas of the Sahel region. Namely, Liberia, Côte d'Ivoire, and southern portions of Ghana picked up as much as 200 mm locally. Other isolated showers were further north in Guinea and southern Senegal, but rainfall totals only reached 50 mm. Through central and eastern portions of Africa the ITCZ remained slightly north (central areas) or near climatology (eastern). Most of the widespread rain showers were confined to southern Chad where amounts were up tp 75 mm and in southern Sudan, where isolated amounts reached greater than 100 mm.

October 1-10 2003 - The Intertropical Convergence Zone over Africa was located near 15.0 degrees north latitude, or around 0.3 degrees south of the 1988-2002 normal for the period. The rate of descent was much less however, as the ITCZ only moved around 0.6 degrees southward since the end of September. Comparing ITCZ location and accumulated precipitation with recent periods, little change has taken place in overall spatial extent of rainfall, likely due to the small degree of southward movement. Major differences were seen in the form of decreased west Ethiopian and Guinean precipitation though. Both western and eastern regions of the ITCZ are currently located near normal compared to the long term mean. If the next few periods resemble the average trend in ITCZ movement, a quick southward movement of around 1.5 degrees will occur each ten days.

September 21-30 2003 - The Intertropical Convergence Zone over Africa was located near 15.6 degrees north latitude, or around 0.4 degrees south of normal. The average position of the ITCZ moved around 1.4 degrees south from the previous ten days, while the normal movement for the same period is closer to 0.9 degrees south. The ITCZ moved sharply south over Niger, Chad, and Sudan, while little movement was seen further west. Overall, the current ITCZ is very near the 1988-2002 mean position. Associated with the movement south, a sharp decrease in rainfall was seen over much of central Mali, southern Niger, and northern Burkina. Rainfall continues to creep southward into southern Ethiopia. In both the western and eastern regions, the current ITCZ is very near the average position for the period, and the early peak of the northward extent does not at this time seem to be affecting the eastern season to a high degree. >

September 11-20 2003 - The Intertropical Convergence Zone over Africa is located near 17.0 degrees north latitude, which is about 0.4 degrees north of normal for the current period. This is around 0.7 degrees south from the previous period and about 3.0 degrees south of its maximum northward seasonal position. The rainfall accumulations in the western Sahel correspond to the slightly southward anomaly in the ITCZ as compared to the 1988-2002 climatological mean. The heaviest showers continue in southern Senegal, northern portions of Guinea, and Guinea Bissau as the convergence zone continues its southward migration. Rains also increased along the Gulf of Guinea region, mainly over Liberia and southern Côte d'Ivoire and Ghana. Western and eastern ITCZ regions show a continued general trend of the southward movement if the ITCZ. The region from 10 degrees east to 10 degrees west longitude (western ITCZ region) is very close to the climatological mean, while the convergence zone from 20 degress to 35 degress east (eastern ITCZ region) remained similar to the last 10-day period, which was slightly north of the mean.

September 1-10 2003 - The African portion of the Intertropical Convergence Zone was located on average near 17.7 degrees north latitude, or around 0.3 degrees north of normal for the period. The latest location is nearly 0.6 degrees south from the previous period and around 2.3 degrees south of its maximum northward position this season. Rainfall patterns from the current and most recent periods over the region are similar, with heavy rains seen in southern Senegal, much of Nigeria, and northwestern Ethiopia, and lighter rains along southern Côte d'Ivoire and Ghana. Rains did increase though in parts of northern Senegal and were associated with a northward movement of the ITCZ on September 7-9. Rainfall also was seen to increase southward toward the Gulf of Guinea region as the convergence zone pushes to the south. Both western and eastern ITCZ regions show the continued movement to the south, though the area from 10W-10E is currently located much further northward than the average area between 20-35E. This is fairly standard though, with this characteristic of the ITCZ seen normally during this time of the year.

August 21-31 2003 - The African region of the Intertropical Convergence Zone continued to move southward from its position during the previous dekad. It can now be stated with confidence that the ITCZ reached its peak northward position in 2003 during the first ten days of August. Since then, the ITCZ has moved almost 1.7 degrees south and is currently located near 18.3 degrees north latitude. This is near the climatologically-normal position for the period. Comparing current 10-day rainfall with that of the previous period shows that rainfall has remained heavy in parts of southern Senegal, western Burkina, northwestern Nigeria, and northwestern Ethiopia, while rains have began to move toward Gulf of Guinea area. Examining the western ITCZ region (from 10W-10E), the average position moved around 0.8 degrees south from the previous dekad and is currently located near 0.1 degrees south of normal. In the eastern area (20-35E), the ITCZ moved around 0.3 degrees south from last period and is now located nearly 0.7 degrees north of normal.

August 11-20 2003 - The African portion of the Intertropical Convergence Zone appeared to begin its transition southward, as the longitudinal averaged position was located around a full degree south from its position during August 1-10. If this does indeed mark the beginning of the ITCZ's southward movement, this year's peak position would have occurred around ten days earlier than climatologically normal. The 2003 peak northward location of around 20.0 degrees north would also be around 1.4 degrees north of the normal maximum northward position. The fact that the ITCZ has been located north of normal since around mid-June has led to a two-faced situation throughout much of the Sahel and western Africa. The northward bias of convective activity has led to enhanced rainfall across much of Africa between 10 degrees north and the Sahara Desert. Some regions to the south, however, have experienced locally severe dryness with much less rainfall than usual during the season.There has been locally heavy rainfall in parts of southern Senegal, Gambia, and Guinea-Bissau as well as east of Khartoum in eastern Sudan. Favorable conditions are generally seen elsewhere.

August 1-10 2003 - The African portion of the Intertropical Convergence Zone continued moving to the north with a similar rate of the previous period. The overall average position during the first ten days of August was near 20.0 degrees north, around 1.5 degrees north of the climatologically normal location and just under a degree north of its position during July 21-31. Compared to the previous period, precipitation increased in eastern Senegal, southern Mauritania, and western Mali but decreased somewhat in eastern Ghana. Even with the northward bias of the western ITCZ region, western Senegal has remained dry for most of the season. Abnormally heavy rains were noted in northern Mali and southern Algeria as well as parts of western Niger. Although very heavy rains did not continue further east into southern Chad and eastern Sudan, rains were plentiful nonetheless. In the western region (10W-10E) in 2003, the ITCZ reached the normal maximum northward extent in early July and has continued to move north into the Sahara. This has led to increased abnormal rainfall throughout parts of western Africa during the past few weeks. A similar situation exists in the eastern region (20-35E), as the ITCZ continues to be north of the 1988-2002 mean position.

July 21-31 2003 - The Africa region of the Intertropical Convergence Zone was located near 19.1 degrees north latitude when averaged from 15W-35E longitude. This is around 0.9 degrees north of its climatological position for the period and around 0.9 degrees north from the previous 10 days. When comparing the latest ITCZ position to precipitation over the same period, rainfall generally increased in coverage in the east and decreased overall in the west. In Ethiopia, eastern Sudan, and southwestern Eritrea, moderate to heavy rains fell during the period, with extreme amounts east of Khartoum causing flooding problems. In contrast, portions of southwestern Nigeria, southern Togo, Benin, Ghana, Côte d'Ivoire, and Liberia received virtually no rainfall during the period. Examining the western region of the ITCZ (10W-10E), it is noted that a northward bias continued during the period, with the average position nearly half a degree north of normal. Associated with this bias, increased rainfall was seen in parts of Senegal and western Mali. While the western track seems to be nearing its maximum northward extent for the season, the east (20-35E) continues to move northward above the climatological normal. Ideally, this should continue to enhance precipitation over Ethiopia, Sudan, and Eritrea. The ITCZ normally reaches its peak northward position during the middle of August.

July 11-20 2003 - The African portion of the Intertropical Discontinuity slowed its overall northward movement, and was located near 18.2 degrees north latitude when averaged from 15W-35E longitude. This places the ITCZ around 0.4 degrees north from its position during the first ten days of July; a small movement compared to the previous progression of around 1.1 degrees northward. Although much of the Sahelian region saw an ITCZ with little movement from the previous period, the region from 15W-0E saw a jump northward due to stronger-than-normal southerly winds pushing into the area. These winds from the south helped to spread rainfall throughout much of the western Sahel as evident in increased ten-day total precipitation into Guinea, Côte d'Ivoire, Liberia, and Ghana. Rainfall during the current period was lighter though in parts of southern Mali and in Burkina in western Africa. In the east, rainfall was generally similar to as seen during the first 10 days of July. Examining the western region of the ITCZ, the current position (near 19.8N) continues to be displaced northward of normal (~18.4N). The western region (from 20-35E) shows a smaller northward bias of around a degree for the current period. Both western and eastern region ITCZ average positions have already reached their normal maximum northward extent, almost a month early, and the possibility for further movement to the north continues to exist.

July 1-10 2003 - The African ITCZ continued its movement northward and was again located to the north of the 1988-2002 mean position for the period. While the current average position from 15W-35E was near 17.8N, the long term mean was closer to 16.3N. Associated with the northward movement, seasonal precipitation is increasing into central Sudan, central Chad, and southern Mali. The current northward bias is also undoubtedly connected to unseasonable dryness found in parts of Ghana, Côte d'Ivoire, Liberia, and Sierra Leone. Dryness in Liberia, particularly, is the most extreme noted during at least the past few years. Both western and eastern zones of the ITCZ remain north of normal, and although the western bias is decreasing, the separation between climatology and current position in the east is expanding. Both current western and eastern positions are already near the usual maximum northward location during a season.

June 21-30 2003 - The African ITCZ moved markedly northward from the previous period in almost all locations from 15 degrees west to 35 degrees east. While last period's overall average ITCZ position was near 15.2 degrees north latitude, the average position from June 21-30 was closer to 16.7N. This average 1.5 degree push northward was accompanied by healthy rainfall moving towards central Niger, Chad, and Sudan, and increased precipitation locally in southern Senegal, southern Mauritania, and southern Eritrea. Associated with the movement of convergence northward, parts of coastal Côte d'Ivoire, Ghana, and Liberia saw lighter ten day rainfall totals. In western Africa, the ITCZ, which has been generally following climatological patterns, remained north of normal for most of the month of June, and is currently located near 18N, or around 1.3 degrees north of the 1988-2002 normal. In the west, the ITCZ has continued its rebound from a southward bias during the months of April and May and has remained near normal for the past forty days. The current position in this region is near 15.3N or about 1.1 degrees north of normal. This overall northward bias of the ITCZ should encourage continued healthy rainfall conditions throughout most of Sahelian Africa.

June 11-20 2003 - The African region of the Intertropical Convergence Zone moved little overall from its position during the first ten days of the month. Both the climatological mean and the current average ten-day position of the ITCZ is located near 15.2 degrees north latitude when averaged over the entire domain from 15W-35E. Rainfall continued over western portions of the Ethiopian Highlands, and some precipitation was noted in southwestern parts of Eritrea. Southern Sudan, Chad, and most of CAR and Cameroon received moderate precipitation, while overall rainfall decreased throughout much of western Africa. Associated with the current ITCZ position, the northward progression of rainfall is generally normal for the 2003 monsoonal season in western Africa. When looking at western and eastern secions of the ITCZ, each region is near normal compared to 1988-2002.

June 1-10 2003 - From June 1-10 2003, the African portion of the ITCZ moved northward nearly 0.7 degrees from last period, and was located near 15.2N degrees latitude. This places the current zonally-averaged ITCZ position half a degree north of its 1988-2002 mean value. Associated with the current location, rainfall was once again widespread throughout most of southern Sudan, southern Chad, western Ethiopia, and into southern Senegal, Mali, and Niger during the first ten days of June. Rainfall decreased, however, in parts of eastern Ethiopia, southern Somalia, and coastal Kenya in eastern Africa. Further west, rains pushed into southern parts of Senegal and western Mali for the first time this season. Breaking the ITCZ down into eastern and western sections shows that the current convergence zone continues to dip southward in the eastern half of the continent. From 10W-10E longitude, the recent ITCZ average position was near 16.6N, while from 20-35E, values were closer to 13.8N.

May 21-31 2003 - The African portion of the ITCZ was located much closer to its climatologically-normal position, especially in eastern regions. While the ten day average position of the ITCZ was around 0.9 degrees south of normal during May 11-20, the current period has the average position 0.2 degrees north of normal when averaged from 15W-35E longitude. Associated with the northward movement, rainfall increased from the pervious period throughout much of Ethiopia, Somalia, coastal Kenya, southern Sudan, Chad, and virtually all of western Africa. Widespread decreased precipitation was seen only near the Nigeria/Cameroon border and central Burkina Faso. The western region of the ITCZ remained nearly stationary, but the eastern area saw a dramatic northward push during the last 11 days. From 20-35E longitude, the ITCZ moved nearly 3 degrees north from last week and is now located slightly north of its climatologically-normal position.

May 11-20 2003 - The spatially-averaged 10 day position of the Africa ITCZ moved nearly 1.5 degrees northward from its position during the first ten days of May. While the normal average position for the period is near 13.5 degrees north latitude, the latest position is around 12.6N. This is an improvement which has reduced the southward bias seen during the past few periods. The recent northward movement has helped to increase rainfall in areas such as northern CAR, Nigeria, Cameroon, and Burkina Faso. Rains during the period decreased locally in areas of Gabon, western Kenya, and southern Ethiopia. The western region of the ITCZ is located near its climatologically-normal position, and in fact less than 0.2 degrees separation exists when averaged from 10 degrees west to 10 degrees east. More problematic, however, is the eastern region of the African ITCZ. Though the latest position remains south of normal, the difference is decreasing. While the normal 10 day position in this region is near 12.2 degrees north, the May 11-10 mean was closer to 10.6N. The current difference of around 1.6 degrees is less than during the previous period (2.4 degrees).

May 1-10 2003 - The overall average position of the Africa ITCZ remained nearly stationary compared to the last ten days of April. While the current ITCZ position, averaged over ten days from 15W-35E longitude, was located near 11.1 degrees north latitude, the climatological mean location was closer to 12.9N. This substantial overall southward bias of the convergence zone over Africa contributed to ten-day precipitation totals generally much lower than during the last ten days of April. Compared to the previous period, much of Ethiopia, southern Somalia, and eastern Kenya saw dramatically decreased rainfall totals, while locally heavy rains continued in parts of southern Ethiopia and western Kenya. Further west, rains eased throughout most of western Africa, though central Guinea received ten day totals exceeding 100 mm locally. From 10W-10E longitude, the current position in the region is near normal and the northward push in extreme western Africa helped to increase rains in Guinea. This is a bit misleading though, as the current ITCZ is south of normal entirely from 0E-35E. Disturbingly, the May 1-10 average position from 20-35E (9.2N) is almost 2.5 degrees south of normal. The largest bias is currently near the 15 degree east meridian, as a nearly five degree difference exits.

April 21-30 2003 - The western region of the Africa ITCZ remained nearly stationary while the eastern region moved to the south. Overall, the Africa ITCZ was located near 10.9 degrees north, and this was 0.5 degrees south from the previous ten days and 1.3 degrees south from the climatologicall y normal location. See figure 1 for a graphical representation of the current vs previous vs normal position. For the western region from 10 degrees west to 10 degrees east longitude the ITCZ has been located near normal throughout the season as of yet, even though it moved slightly to the south from last ten days. For the eastern Africa region (20-35E) a large 2003 southward bias is seen. In fact, the current average position is 2.0 degrees south from the 1988-2002 normal location, and actually 0.5 degrees south from last period. This southward position of the eastern ITCZ region is evidenced in the lack of rainfall from April 21-30 in parts of southern Chad, northern CAR, southern Sudan, and western Ethiopia. This southward movement of the ITCZ explains the dramatically increased moisture throughout most of Kenya for the period. This enhanced surface convergence over the region also helped to increase precipitation over southern Ethiopia and northwestern Tanzania. Further west, conditions dried out somewhat over southern Nigeria and Cameroon, Liberia, and Côte d'Ivoire.

April 11-20 2003 - The African portion of the Intertropical Convergence Zone moved around 2.2 degrees north from its overall position during the first ten days of the month. This places the ITCZ near 11.4 degrees north latitude for the current period, as opposed to 11.3 degrees north for the 1988-2002 climatological mean. Although the ITCZ is located near its normal position when averaged from 15 degrees west to 35 degrees east, this may be misleading, as there is a northward bias this period over Nigeria/Niger and a southward bias toward CAR and Sudan. From 10W-10E longitude, the current position of around 13.1N is near normal at 12.5N. This region saw the northernmost location of the ITCZ during the recent ten days, around 5-10 degrees east longitude, pushing toward 17 degrees north at times. From 20-35E, although the average location in this area was near normal last period, the ITCZ has slipped south of normal during the current period, and is located near 9.5N (mean~10N). Compared to the period from April 1-10, 2003, this period saw greatly increased precipitation throughout much of Ethiopia (excluding northwestern areas), southern Somalia, central Kenya, and Uganda. Locally in southeastern Ethiopia, southern Somalia, and northeastern Kenya, rainfall amounts totaling greater than 300 mm for the week were seen. Parts of northwestern and southeastern Kenya, along with much of northern Somalia, northwestern Ethiopia, and western Eritrea remained dry however. In the west, heavy rains fell throughout much of coastal and eastern Nigeria and southern Liberia/southwestern Côte d'Ivoire.

April 1-10 2003 - The current location of the ITCZ is generally near normal, especially in the west, compared with the 1988-2002 mean position. In fact, the 2003 April 1-10 position was near 9.2 degrees north latitude on average, or 0.4 degrees north from its position during the final ten days of March. This average position was around a degree south of normal due to a southward bias from Chad to Sudan. The ITCZ in western Africa was near normal last period, with both 1988-2002 mean position and current location near 11.6 degrees north. Stronger than normal southerly winds helped to push the ITCZ north around 1.3 degrees during the period, and associated moisture led to heavier 10 day precipitation throughout much of Togo, Benin, and especially Nigeria. The eastern Africa portion of the ITCZ regained its northward movement this period, and in fact was located around 1.2 degrees north from last period and nearly the same as normal when looking at the 20-35N longitude segment. Although the ITCZ near 35 degrees east longitude was located nearly three degrees north of normal for the period, much of the Greater Horn Of Africa saw dramatically decreased precipitation from April 1-10. Rainfall decreased so substantially that most of Kenya, Uganda, Somalia, and eastern Ethiopia recorded little to no rain during the entire ten days. This will further hurt the agricultural and hydrological situation in the region, especially in Kenya where the rainy season is short to begin with.

March 21-31 2003 - The African portion of the ITCZ was located on average near 8.8 degrees north latitude. This position was around 0.6 degrees north from its position during the previous period, and around a degree north from our initial 2003 analysis. The eastern region behaved much differently than the west with respect to ITCZ movement during the last third of March. The western region’s (10W-10E) ITCZ jumped almost two degrees north from the previous week due to a very strong low pressure center and associated frontal system which moved through northwestern Africa during the first part of the period. This weather event caused strong southerly winds to bring in moisture from the Gulf of Guinea and thus pushed the ITCZ to the north in this region. The ITCZ reached a northward peak of 17 degrees N on March 22. A different pattern is seen in a plot of current vs mean eastern region (20-35E) ITCZ. In this area, the ITCZ retrograded around 0.6 degrees south from the previous period. Examining the current and previous period rainfall estimate product, rains decreased from last period in parts of coastal Nigeria, Togo, and Benin. Associated with the northward push of the ITCZ, parts of Burkina Faso received unusual rainfall with 11-day totals up to 60 mm locally. Much of Kenya, Uganda, and northern Tanzania saw dramatically increased rainfall as well, with local thunderstorms helping to produce ten-day totals exceeding 150 mm locally.

March 11-20 2003 - The African portion of the ITCZ was located on average near 8.2 degrees north latitude, or around 0.4 degrees north from last period. Both western (10W-10E) and eastern (20-35E) regions of the ITCZ moved northward nearly 0.8 degrees from the first ten days of March and were located near 8.6 and 8.0 degrees north, respectively, for the current period. For this period, the minimum average position was found near 15E, with the maximum near 35E. This resembles the max/min position of last period. Examining the precipitation estimated during March 11-20, it is seen that although the ITCZ retrograded slightly southward near 35E, much of Ethiopia received heaver rain than during March 1-10. Heavier rainfall was also noted throughout much of the current map, though parts of eastern Tanzania, western DRC, and southern Congo saw the greatest increases. Sections of Gulf of Guinea countries saw slightly weaker rains for the period.

March 1-10 2003 - The African portion of the ITCZ was located near 7.8 degrees north latitude and the rainfall pattern followed the convergence zone fairly closely. The western region of the ITCZ (from 10W-10E) averaged around 7.8 degrees north latitude as well, though the eastern portion (20-35E) had its mean near 7.2 degrees north. The minimum 10-day mean position for the current period occurred near 15 degrees east longitude, while the maximum northward position was near 35 degrees east. Associated with this position, 10-day rainfall totals in southern Côte d'Ivoire, Liberia, and Ghana were from 10-80 mm, while rainfall totals throughout the highlands of Ethiopia were less than during the previous week and generally totaled less than 50 mm. Moderate to heavy thunderstorms continued to produce locally heavy rainfall (up to 150 mm) in parts of western Gabon, southwestern CAR, and northern and central DRC.


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