ARRL

ARRL Propagation Bulletin ARLP001 (2000)

SB PROP @ ARL $ARLP001
ARLP001 Propagation de K7VVV

ZCZC AP01
QST de W1AW  
Propagation Forecast Bulletin 1  ARLP001
From Tad Cook, K7VVV
Seattle, WA  January 7, 2000
To all radio amateurs 

SB PROP ARL ARLP001
ARLP001 Propagation de K7VVV

For the first propagation bulletin of the new year, we will review
some of the solar numbers for 1999.

Currently we are moving toward the peak of solar cycle 23.  Activity
is not as high as we had hoped, and current projections place the
broad peak of the cycle some time later this year.

We can see a broad progression of the current cycle by reviewing
annual solar flux averages.  The average daily solar flux in 1996,
1997 and 1998 was 70.8, 80.9 and 117.9, and for 1999 it was 153.7.

The average daily solar flux for the four quarters of this year were
136.7, 145, 157.6 and 175.2 for the quarter just ended.  This
indicates a steady upward trend.  Monthly averages of daily flux
values for September through December were 135.7, 164.8, 191.5 and
169.8.

So what does the short term outlook say?  Projected solar flux for
Friday through Sunday is 150, 155 and 160, and the projected
planetary A index is 10, 8 and 12.  Beyond the weekend it looks like
quiet geomagnetic conditions for January 10-19, moderately unsettled
around January 20 and 21, then quiet again until January 26 through
the end of the month.  The most active days should be around January
27 and 28 due to recurring coronal holes.  Solar flux should rise
until January 16 and 17, peaking around 205, the drop below 150 by
January 25.

If you want to graph data from these bulletins, you should try
WA4TTK's graphing program.  The solar flux and sunspot database has
just been updated, so it now covers 11 whole years, from January 1,
1989 to December 31, 1999.  You can download the software and the
data from http://edge.net/~scraig/sol.htm.  Then starting with this
bulletin and for every bulletin after this, you can use the WA4TTK
freeware to import the data automatically from the bulletin text and
display it graphically.

Sunspot numbers for December 30 through January 5 were 88, 91, 69,
69, 77, 102 and 100 with a mean of 85.1. 10.7 cm flux was 135.6,
130.1, 129.9, 132.9, 133.1, 134.7 and 136.5, with a mean of 133.3,
and estimated planetary A indices were 8, 27, 27, 14, 13, 12 and 15,
with a mean of 16.6.

Path projections for this weekend are to Japan for the JA
International DX CW Contest.

From Seattle, WA, 80 meters 0700-1730z, 40 meters 0600-1830z, 20
meters 2030-0430z, 15 meters 2200-0200z, 10 meters 2230-0030z.

From Salt Lake City, UT, 80 meters 0700-1600z, 40 meters 0600-1700z,
20 meters 1530-1630z and 2100-0430z, 15 meters 2130-0130z, 10 meters
2230-0030z.

From Omaha, NE, 80 meters 0700-1500z, 40 meters 0600-1630z, 20
meters 1500-1630z and 2100-0200z, 15 meters 2130-0030z, 10 meters
2230-2300z.

From Dallas, TX, 80 meters 0630-1430z, 40 meters 0600-1500z, 20
meters 2000-0300z and 1430-1530z, 15 meters 2130-0130z, 10 meters
2200-0000z.

From Newington, CT, 80 meters 0700-1330z, 40 meters 0600-1400z, 20
meters 2030-1030z and around 1630-1730z, 15 meters 2200-2300z.

From Miami, FL, 80 meters 0700-1300z, 40 meters 0530-1330z, 20
meters 2100-0100z and 1230-1300z, 1430-1530z and 1630-1700z, 15
meters 2130-0000z, 10 meters around 2230z.

From Cleveland, OH, 80 meters 0700-1430z, 40 meters 0530-1600z, 20
meters 2100-0130z, 0600-0900z and 1500-1700z, 15 meters 2130-2300z,
10 meters possibly around 2200z.
NNNN
/EX