‰ Now 18 WPM transition file follows ‰

Solar indicators rose over the past week, for both solar flux and
sunspot numbers.  The highest were on Tuesday, December 10 when the
sunspot number was 169 and solar flux 175.2.  In an otherwise quiet
week the planetary A index reached 26 on Sunday, December 8, sparked
by a strong solar wind surging from a coronal hole.  We could see a
repeat this weekend.  Geomagnetic activity during the ARRL 10 Meter
Contest this weekend should be more active than contesters would
prefer, with predicted planetary A index values of 20 and 15 on
Saturday and Sunday.  NOAA said Thursday night that the geomagnetic
field may be anywhere from quiet to minor storm levels this weekend.
For the past six 10 Meter Contests, geomagnetic conditions have been
very quiet.  But in 2006 the contest, always the second full weekend
in December, fell right between two very active periods.  The 2006
contest was held on December 9 and 10, and we see the planetary A
index on those dates was 7 and 14.  But just prior on December 6 the
A index was 28, and 25 on December 7 and 8.  Following the contest
that year the planetary A index on December 11 to 15 was 15, 26, 5,
63 and 104.  The last two figures indicate a major geomagnetic
storm.  Lucky it didnt hit earlier, but the contest weekend was
still feeling the effects of the higher activity in the days before.
Reports included much trans equatorial propagation.  North South
propagation across the equator is not enhanced during periods of
high geo activity, but rather that is often the only propagation
path available.  Compared to the previous seven days, over December
5 to 11 the average daily sunspot number rose from 102.9 to 122.1,
and average daily solar flux increased from 132.9 to 162.4.  The
predicted values in the 45 day outlook for solar flux took a
substantial leap on December 8.  For example, on December 7 the
predicted average solar flux for December 10 to 15 was 141, and on
December 8 the projected average for the same period was 170.  The
predicted values for the following 45 days increased across the
board, but have since scaled back somewhat.  The latest prediction
has solar flux at 165 on December 13, 160 on December 14 and 15, 155
on December 16 to 18, 150 on December 19 and 20, 172 on December 21
and 22, 175 on December 23 to 25, 172 on December 26, 170 on
December 27 to 29, 165 on December 30, and 160 on December 31
through January 2, 2014.  After dipping to 150 on January 4, solar
flux is expected to rise to a short term peak of 172 on January 7
and 8.  Predicted planetary A index is 12, 20 and 15 on December 13
to 15, then 5 on December 16 to 25, then 12, 10 and 8 on December 26
to 28, 5 on December 29 through January 2, 2014, then 10, 20, 15, 10
and 8 on January 3 to 7.  OK1HH believes the geomagnetic field will
be quiet December 13 and 14, mostly quiet December 15, quiet to
unsettled December 16, quiet December 17 and 18, quiet to unsettled
December 19, quiet December 20 and 24, mostly quiet December 25,
quiet to unsettled December 26, quiet to active December 27, quiet
December 28, mostly quiet December 29, and quiet on December 30 and
31.  Predicted solar flux shows this weekends 10 Meter Contest
should have the highest solar flux and sunspot numbers since the
2002 contest.  Conditions may be similar to the 1999 contest, when
solar flux and sunspot numbers were about the same as now.  This was
before the peak of the last solar cycle, cycle 23.  Over the same
period using the same method, average sunspot numbers were 66.7,
153.3, 120.3, 70.7, 201.3, 202.3, 41.3, 27, 55.7, 22.7, 34, 4.7, 13,
27, 103 and 32.7.  We dont have a source for predicted daily sunspot
numbers, but the average reported at the end of this bulletin was
122.1.  This is also stronger than any contest weekend since 2002.
 
‰ End of 18 WPM transition file ‰