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This is an off schedule propagation bulletin based on last Fridays
release, Propagation Forecast Bulletin ARLP011.  There will be
another off schedule bulletin on Thursday, March 20, because ARRL
headquarters will close for the Good Friday holiday.  The reason for
this Monday morning bulletin is to correct some bad data we obtained
from issue 1697 of the weekly Preliminary Report and Forecast of
Solar Geophysical Data from the NOAA Space Weather Prediction
Center.  Readers who clicked on the link to issue 1697 in last weeks
bulletin may have wondered what we were referring to when we
heralded a new prediction for a more robust Cycle 24, and talked
about changes from the first week of January forecast in issue 1687.
After I emailed a forecaster in Boulder about the new prediction, he
responded What new prediction?, and Friday morning corrected the
data.  Apparently nobody had noticed the new numbers, in a table on
page 9 of issue 1697, when it was released on Tuesday.  I sent my
email Thursday night, and I understand they are reviewing the
process used to publish these numbers.  They were so sorry about the
mistake that they even offered to let me be announcer for a day on
the 18 minutes after each hour bulletin of solar flux and
geomagnetic data transmitted by WWV, if I ever visit Colorado.  Cant
be sure if they were serious, but I promised not to use my own call
sign.  I understand that currently the numbers for the table are
hand typed, with the data coming from the swpc.noaa.gov site.  The
URL ending in high.txt shows the prediction from the forecast team
that believes the next cycle will be robust, and the URL ending in
low.txt is from the group which thinks Cycle 24 will be weak.  They
have averaged the two predictions.  Note that all three tables show
a high and low range, and these reflect what each team thinks the
likely range of values could be.  Note that both teams predict the
cycle bottom was in February 2008.  Last months value is still a
prediction, because these are smoothed sunspot numbers, averaged
over a year.  So Februarys numbers are an average of actual monthly
numbers for the past six months, and the predicted values for the
following six months.  The low team predicts a smoothed sunspot
number of 90 at the peak of Cycle 24 in August, 2012.  The high team
says Cycle 24 should peak much earlier in September or October 2011,
at 139R9.  And the average of the two shows a peak of 113R1 in
January, 2012.  In the past few days a sunspot has reappeared, with
the emergence of sunspot 986.  But it is way over on the Suns west
limb, and will shortly pass from view.  Sunspot numbers were 12, 0,
0, 0, 12, 0, and 0 with a mean of 3R4.  10R7 cm flux was 70R3, 70R5,
69R8, 69R5, 70R3, 70R2, and 69R4 with a mean of 70.  Estimated
planetary A indices were 2, 3, 11, 25, 18, 12 and 14 with a mean of
12R1.  Estimated mid latitude A indices were 2, 1, 6, 14, 12, 7 and
9, with a mean of 7R3‚

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