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SB PROP @ ARL
$ARLP005
ARLP005 The
ARRL Solar
Report
ZCZC AP05
QST de W1AW
Propagation
Forecast
Bulletin 5
ARLP005
From ARRL
Headquarters
Newington, CT
January 30,
2026
To all radio
amateurs
SB PROP ARL
ARLP005
ARLP005 The
ARRL Solar
Report
Solar activity
continued at
low levels
this week.
Low-level
C-class flares
were observed
from Regions
4342 and 4353.
The majority
of the regions
were either
stable or in
decay.
New Regions
4359, 4360,
and 4361
emerged on the
disk and were
numbered.
No
Earth-directed
Coronal Mass
Ejections
(CMEs) were
observed. The
forecast calls
for solar
activity to
remain at low
levels with a
chance for
M-class flares
(R1-R2/Minor-Moderate) through January 31.
Solar wind
parameters
reflected a
solar sector
boundary
crossing
followed by
the likely
onset of
high-speed
stream (HSS)
conditions. On
January 27,
phi angle
switched into
a negative
sector.
Solar wind
speed began to
increase after
January 28 to
around 610
km/s.
Enhancements
in the solar
wind
environment
are expected
through
January 31
under negative
polarity
Coronal Hole
High Speed
Streams CH
HSS)
influences.
The
geomagnetic
field is
expected to
quiet to
unsettled
levels on
January 31,
and quiet
levels on
February 1.
Solar activity
is expected to
be
predominantly
low with a
varying chance
for M-class
flares
(R1-R2/Minor-Moderate)
through
February 21.
No proton
events are
expected at
geosynchronous
orbit.
The greater
than 2 MeV
electron flux
at
geosynchronous
orbit is
expected to
reach high
levels on
January 31,
and then on
February 1 to
3. Normal to
moderate flux
levels are
expected to
persist
through the
remainder of
the period.
Geomagnetic
field activity
is likely to
reach G1
(Minor) storm
levels on
February 13,
with active
periods likely
on February 4
and 5 due to
the influences
of multiple,
recurrent CH
HSSs.
Quiet and
quiet-to-unsettled
conditions are
expected to
prevail
throughout the
remainder of
the outlook
period.
Weekly
Commentary on
the Sun, the
Magnetosphere,
and the
Earth's
Ionosphere,
January 29,
2026, by F. K.
Janda, OK1HH:
"The number of
sunspot groups
has ranged
between eight
and ten in
recent days,
but these are
mostly
magnetically
simple areas
with low
eruptive
activity.
However, the
solar wind is
blowing faster
and faster
from the Sun,
resulting in
increased
geomagnetic
activity,
especially
since January
28. Although
this was
expected, the
combination of
fast solar
wind, while
rapid and
significant
changes in the
polarity of
the
interplanetary
magnetic field
has had
atypical
consequences
in the
ionosphere.
These include
numerous
occurrences of
ionospheric
waveguides on
January 28 and
during the
night of
January 29.
"In the coming
days, solar
and
geomagnetic
activity
should
continue to
decline.
The next
increase in
geomagnetic
activity can
be expected in
the middle of
the first week
of February,
but this time
without the
major
influence of
high-speed
solar wind.
Therefore,
only a
decrease in
critical
frequencies
and an
increase in
attenuation
are expected
in the
ionosphere
until February
6, followed by
a return to
average values
is expected."
The latest
solar report
by Dr. Tamitha
Skov, WX6SWW,
can be found
on YouTube at
https://youtu.be/JXKADnd1E8w?si=pTrl5bAwGvvajUuF.
The Predicted
Planetary A
Index for
January 31 to
February 6 is
8, 5, 5, 5,
15, 12, and
10, with a
mean of 8.6.
Predicted
Planetary K
Index is 3, 2,
2, 2, 4, 4,
and 3, with a
mean of 2.9.
10.7-centimeter
flux is 120,
120, 130, 140,
140, 130, and
120, with a
mean of 128.6.
For more
information
concerning
shortwave
radio
propagation,
see www.arrl.org/propagation
and the ARRL
Technical
Information
Service web
page at www.arrl.org/propagation-of-rf-signals.
For an
explanation of
numbers used
in this
bulletin, see
www.arrl.org/the-sun-the-earth-the-ionosphere.
Information
and tutorials
on propagation
can be found
at http://k9la.us.
Also, check
this:
"Understanding
Solar Indices"
from September
2002 QST.
NNNN
/EX
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