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January 08
Temperatures fell as the sun lowered in our hemisphere.
Our average temperature this month was -29.9? C (-21.8?
F). Along with temperatures dropping, we had clear skies
and many hours of solar radiation. Ten out of thirty one
days were clear and a total of 622.9 hours of solar radiation
were recorded, averaging 20.8 hours per day. There were
two wind related records broken, both occurring on the
10th. The daily peak wind speed of 27kts/31mph broke the
previous daily peak wind speed of 25kts/29mph set in 1986.
Also, the daily average wind speed of 18.8kts/21.7mph
broke the previous highest daily average wind speed of
17.5kts/20.1mph set in 1986.
February 08
Temperatures continued to fall as the sun lowered. Our
average temperature was -41.6? C (-42.9? F). Along with
temperatures dropping, skies were mostly clear on the
majority of days and had many hours of solar radiation.
Six out of twenty-nine days were clear, thirteen were
partly cloudy, and a total of 487.4 hours of solar radiation
were recorded, averaging 16.8 hours per day. There were
no new wind records set. Temperatures in the first half
of the month were colder than average. There were four
daily minimum temperature records broken, occurring on
the 1st, 2nd, 3rd, and 7th. The record minimum temperature
on the 7th was exaggerated by the occurrence of an 82%
solar eclipse.
March 08
Temperatures have continued to fall as the sun lowered
and set in our hemisphere. Sunset occurred at 0822 UTC
on March 22nd. It was not directly observed due to overcast
sky condition, so the recorded sunset time is the U.S.
Naval Observatory calculated time. Our average temperature
this month was -53.4? C (-64.1? F). Eleven out of thirty-one
days were clear, fourteen were partly cloudy, and six
were cloudy. There were no new wind records set. Although
the average monthly temperature was only slightly warmer
than the historical average, daily temperatures varied
widely this month. On March 13th and 14th, the daily low
temperatures of -64.8? C (-84.6? F) were less than three
Celsius degrees away from the record low temperatures.
A week later on March 21st, a new record high of -35.9?
C (-32.6? F) was set. There were also nine days with surface
visibility of less than ¼ mile, mainly due to blowing
snow.
April 08
The average monthly temperature was -54.2?C (-65.6?F)
which was 3.1?C warmer than the historical average. This
trend was fueled mainly by two warm systems on the 9th
and the 24th-26th of the month, which brought cloudy skies
and prevailing winds from the north-northeast. Sixteen
out of thirty days were clear, nine were partly cloudy,
and five were cloudy. The average wind speed of 10.7 knots
was slightly less than the historical average, but one
new peak wind record of 30 knots was set on April 9th.
The average pressure of 684.2 millibars was also higher
than the historical average of 680.3 millibars. Two new
maximum temperatures were set with -36.8?C (-34.2?F) on
April 9th and -33.5?C (-28.3?F) on April 25th. There were
also seven days with surface visibility of less than ¼
mile, mainly due to blowing snow.
May 08
May's average monthly temperature was -59.1?C (-74.4?F)
which was only 1.1?C colder than the historical average.
We experienced a warm system with cloudy skies and winds
from the north-northwest on the 16th and 17th, and several
cold spells with temperatures in the -66.8?C to -69.7?C
range that mostly corresponded with winds from the higher
polar elevations to the east-southeast, but most of the
month's weather was fairly unremarkable and close to the
historical average values. Fifteen out of thirty-one days
were clear, fourteen were partly cloudy, and two were
cloudy. The average wind speed of 8.2 knots was less than
the historical average of 11.9 knots, but no new wind
records were set. The average pressure of 680.6 millibars
was also very close to the historical average of 680.0
millibars. No new maximum or minimum temperature records
were set for the month. Surface visibility of less than
¼ mile occurred on only one day. This was due to
blowing snow, which accounted for the majority of visibility
restrictions that occurred on other days as well.
June 08
The average monthly temperature was -61.8?C (-79.2?F)
which was -3.2?C colder than the historical average. We
experienced a warm system with mostly cloudy skies and
winds from the north-northwest on the 7th and 8th, and
several cold spells with temperatures in the -70.1?C to
-71.4?C range that mostly corresponded with winds from
the higher polar elevations to the east-southeast. Twenty
out of thirty days were clear, nine were partly cloudy,
and one was cloudy. The average wind speed of 7.8 knots
was less than the historical average of 12.1 knots, continuing
this winter's trend of below average wind speeds. The
average pressure of 677.7 millibars was also less than
the historical average of 681.0 millibars. No new maximum
or minimum temperature records were set for the month.
Surface visibility of less than ¼ mile was not
observed. No new wind speed records occurred.
July 08
July's average monthly temperature was -57.1?C (-70.8?F)
which was +2.9?C warmer than the historical average. There
were several warm systems on the 12th-13th and the 25th-28th
that drove this warm average, and the only particularly
cold snap occurred on the 10th. Fifteen out of thirty
days were clear, twelve were partly cloudy, and four were
cloudy. Though the average wind speed of 10.9 knots was
less than the historical average of 12.5 knots, we had
several systems from the north/northeast that brought
the periods of sustained winds over 20 knots that are
more typical of South Pole winters than the relatively
calm winds we have been experiencing for most of this
season. The average pressure of 675.2 millibars was also
less than the historical average of 676.9 millibars. No
new maximum or minimum temperature records were set for
the month. Surface visibility of less than ¼ mile
was observed on 7 days. No new wind speed records occurred.
August 08
The average monthly temperature of -60.1?C (-76.2?F) was
just -0.4?C colder than the historical average. We had
warm systems on the 2nd-3rd and 7th-8th with cloudy skies
and winds from the north, and a particularly cold spell
on the 17th that brought the winter's lowest temperatures
so far. Twelve out of thirty-one days were clear, sixteen
were partly cloudy, and three were cloudy. The average
wind speed of 12.7 knots was only +0.1 higher than the
historical average of 12.6 knots, and like July, there
were several periods of sustained winds over 20 knots
that are more typical of South Pole winters than the relatively
calm winds we experienced in earlier months. The average
pressure of 670.1 millibars was also 5.6 millibars less
than the historical average of 675.7 millibars. No new
maximum or minimum temperature records were set for the
month. Surface visibility of less than ¼ mile was
observed on 7 days. No new wind speed records occurred.
September 08
The average monthly temperature of -53.9?C (-65.0?F) was
considerably warmer than the historical average of -59.1?C
(-74.4?F). This was fueled by very warm systems on the
3rd-5th and on the 11th, and by generally warmer temperatures
overall throughout the month. Three out of thirty days
were clear (tying a minimum record set in 2006), sixteen
were partly cloudy, and eleven were cloudy. The average
wind speed of 10.9 knots was lower than the historical
average of 12.3 knots, but this statistic was mostly driven
by an extended period of low winds from the 9th-12th.
Average winds during the rest of the month were more typical
of winter and included several sustained gusty periods.
The average pressure of 677.3 millibars was only 1.6 millibars
higher than the historical average of 675.7 millibars.
On September 4th, the maximum temperature of -33.7°C
(-28.7°F) broke the previous daily record high of
-39.2°C (-38.6°F) set in 1976. Surface visibility
of less than ¼ mile was observed on 7 days. A new
wind record occurred on the 10th with the daily average
wind speed of 2.3 knots breaking the lowest average wind
speed of 5.6 knots set in 2005.
October 08
The average monthly temperature of -51.5?C (-60.7?F) was
close to the historical average of -51.1?C (-60.0?F).
A warm system on the 17th came with overcast skies and
winds from the north, and the coldest temperatures were
seen on the 1st. Temperatures increased throughout the
month as the sun rose higher in the sky. Six out of thirty-one
days were clear, twelve were partly cloudy, and thirteen
were cloudy. The average wind speed of 8.7 knots was lower
than the historical average of 12.0 knots. The average
pressure of 674.7 millibars was 2.1 millibars lower than
the historical average of 676.8 millibars. No new temperature
or wind speed records were set. Surface visibility of
less than ¼ mile was observed on 4 days. No other
monthly records were set.
November 08
The cold air of October trickled into the first couple
of days of November before it was scoured away by a storm
system which brought low clouds, gusty winds, and warmer
air on the 3rd through the 5th. It was during these three
days that daily record high temperatures were set. This
intrusion of warmer weather was short-lived though, as
sunshine, along with colder than normal conditions, returned
for much of the remainder of the month. These cold conditions
resulted in a monthly average temperature of -38.7°C/-37°7F,
which was 0.5°C/0.9°F below normal. The prevailing
wind was from grid northeast at 9.2kts/10.6mph. The abundance
of grid northeast and east wind, a katabatic wind, was
responsible not only for the colder than normal temperatures,
but also played a role in the lower than normal average
monthly pressure of 678.3mb/20.030"Hg. This monthly
value was 4.4mb (0.130"Hg) lower than normal. The
average daily amount of sunshine (21.1 hrs, or 88%) was
also indicative of the clear and cold month. November
also yielded a total of seven clear days, fourteen partly
cloudy days, and nine cloudy days, although the majority
of the cloudy days were days with a very high, thin cirrostratus
cloud layer.
December 08
The first half of the month was relatively free of clouds,
but low level moisture and a strong pressure gradient
brought bouts of mist and periods of blowing snow to the
pole. Although the horizon was fuzzy, the lack of clouds
kept temperatures slightly cooler than normal during the
first half of the month. The second half of the month
was much more eventful, with storm systems moving in off
the Weddell Sea on an almost constant cycle. This kept
the moisture and winds in place, but also brought clouds
and snow grains. One particular storm on the 23rd produced
the peak wind gust of 27kt/31mph. Another potent storm
brought strong winds, freezing fog, and unseasonably warm
temperatures to the pole between the 29th and the 31st.
In fact, on the 31st the temperature rose above the zero
degree mark, reaching a daily record high of -17.5°C/+0.5°F.
With a number of storms moving through the region it was
expected that there would be a good accumulation of snow
at the snowstake field. However, the net change in the
field was only +0.004". Other highlights for the
month included a new record in terms of the monthly minimum
station pressure. The new record, 667.6mb/19.714"Hg,
broke the old record of 670.0mb/19.785"Hg set in
1999. The overall average monthly pressure was 4.7mb/0.139"Hg
lower than normal and the average monthly temperature
was 1.2°C/2.1°F warmer than normal. The station
averaged 19.0 hours of sunshine (79% of normal). And,
although it was a particularly unsettled month in terms
of weather, there were zero days in which the visibility
dropped below one quarter of a mile.
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