IRI Climate Information Digest - October 1999
Issued 13 November 1999
Temperature in Percentiles (NOAA CPC CAMS)
1961-1990 Base Period
Historically in October, the primary
global rain belts retreat southward following the sun and ocean temperatures.
The peak of the tropical storm season in the northern hemisphere has passed,
and on average draws to a close in November.
Rainfall observations indicated
a late end to the monsoon seasons in Mexico, central Africa and India
as rains continued well into October. Wetter than average conditions in
Mexico and India were exacerbated by tropical storm activity.
Tropical Storm activity has been above
average in the Atlantic, with 11 named storms compared with an average
of 9.8 for the period 1944-1996. In contrast the eastern Pacific
has seen only 9 named storms through October where on average 16
have been observed for the period 1966-1996.
Tropical Pacific: A moderate La Niña
(colder than average sea surface temperatures) is continuing in the tropical
Pacific Ocean. The La Niña is expected to persist through the next
Extratropics: Warmer than average temperatures
continue to evolve in the northwestern Pacific basin.
Africa: Seasonal rains continued into late
October across much of central Africa and into Ethiopia.
South Asia: The western region of India and
Pakistan received much-needed late season rainfall, while excessive rains
from two consecutive cyclones inundated the east coast of the subcontinent
Mexico: Above average rainfall in southern
Mexico was associated with the remnants of a tropical depression.
South America: Northeastern Argentina, Uruguay,
Paraguay and Southern Brasil have experienced drier than average conditions
since late August.
Western Europe: Spain, France and England
received above average rainfall.
Seasonal Temperature and Precipitation
Northern Hemisphere: Above average temperatures
prevailed over central Asia the Middle East and North Africa.
South America: The north coast, central Brazil
and the Southern Cone experienced persistent above average temperatures.
Australia: The eastern half of Australia was
warmer than average for most of October.
On Fisheries, Agriculture, Health and Hazards.