1. Northern Hemisphere
The 500-hPa circulation
pattern during November featured persistent positive height anomalies in the
, in the area south of
, and from northwestern
, and persistent negative height anomalies over the western and central
North Pacific (Figs. E9, E11).
The main surface temperature departures reflected above-average temperatures
, in the high latitudes and subtropical latitudes of the
, and across northern and eastern
(Fig. E1). The main precipitation departures
included above-average totals in the northeastern
, and below-average totals in the south-central
and portions of both eastern Europe and central
(Figs. E3, E5, E6).
During November, a persistent
pattern of above-average heights at 500-hPa covered western
(Figs. E9, E11),
and contributed to exceptionally warm temperatures over large portions of
. The largest positive temperature departures were observed in
, where monthly temperatures averaged 3°-4°C warmer than normal. In the
, monthly temperatures averaged 2°-3°C warmer than normal. For both
regions, these anomalies were above the 70th percentile of
Precipitation was below
average (in the lowest 30th percentile of occurrences) in the
regions of the
, and in portions of eastern Europe (Fig. E3).
Each of these areas was situated in anomalous descending motion between the
mean upper-level ridge and trough axes (Fig. E9).
North Atlantic Hurricanes
The extremely active 2005
Atlantic hurricane season produced an additional three named storms during
November (TS Beta, TS Delta, H Epsilon), with all occurring during the
second half of the month. By the
end of November, the 2005 season had featured a record 26 named storms, a
record of 14 hurricanes, and 7 major hurricanes. The previous record of 21
tropical storms was set in 1933, and the previous record of 12 hurricanes
was set in 1969.
The 500-hPa circulation
pattern during November featured a persistent pattern of positive height
anomalies over the central
, and extending from western
(Fig. E11). These conditions were
associated with a pronounced split-flow pattern over
. They were also associated with an enhanced poleward transport of
relatively mild, maritime into northern
within the northern branch of the split-flow. This anomalously warm air
overspread much of
, resulting in the well above-average temperatures from
. The most anomalous warmth
, where temperatures were 4°-7°C above average.
2. Southern Hemisphere
The mean 500-hPa circulation pattern during November
featured above-average heights southeast of Australia and over the high
latitudes of the eastern South Pacific, and below-average heights southwest
of Australia, over the central South Pacific, and across southern South
America and the western South Atlantic (Fig. E15).
Positive surface temperature anomalies were observed over the eastern half
and most of
, with monthly mean temperatures in both regions exceeding the 70th
percentile of occurrences.
the rainy season normally lasts from October to April. Rainfall was slightly
above average in this region during November, following well above-average
rains during October (Fig. E4). In November,
the largest positive rainfall anomalies occurred in southeastern
, and near-normal totals occurred elsewhere.