[net.ham-radio] ARRL PROPAGATION FORECAST NR 9

wheatley@inuxi.UUCP (Steven Wheatley) (03/04/86)

qst de k9eui
hr propagation forecast bulletin nr 9  from arrl headquarters
newington ct  march 3, 1986
to all radio amateurs

as you may have observed, conditions on 14, 21, 24 and  28  mhz
have  been  running  better  than  predicted by the monthly qst
propagation charts much of the time since early  february.   if
you  copy  solar  flux information from wwv daily you know why.
the solar flux reached 103, 30 points  above  the  base  figure
used  for  the qst charts, on february 5 and it was at or above
the base figure most of the time, except for a  few  days  just
after the middle of february.

the solar flux is currently following its february curve almost
exactly.  it was up to 89 at bulletin time, high enough to make
things hot for the arrl dx contest phone weekend, march  1  and
2.   the  first of two active areas of the sun, responsible for
the february peak came around the east limb of  the  sun  again
march  2, still looking lively. the flux is running higher than
would be expected from that one group, so  the  second  may  be
contributing, as it did last month a few days before its actual
appearance around the east edge of the solar disk.

fast  rising  solar  flux  curves  mean  increased  geomagnetic
activity,   and   increasing   absorbtion   of  signal  energy,
especially on high latitude  paths.   such  conditions  may  be
accompanied by increased signal levels and higher muf, on north
south paths and other low latitude or transequatorial circuits.
these  effects  were  common during early february, even to the
extent of 50 mhz openings to south america, and  major  auroral
periods  on  144,  220 and even 432 mhz.  watch for more of the
same around march 8 and 9.  more  conventional  propagation  is
generally  good  just  before and just after such disturbances.
watch  march  3  through  5  and  10  through  11.   our  lower
frequencies  should  be working well around the middle of march
and whenever the wwv k index is 2 or lower and the  solar  flux
is in the low 70s or high 60s.

american sunspot  numbers  for  february  20  through  26  were
between 0 and 6 with a mean of 2.6  ar