\n<\/p>\n
A Coronal Mass Ejection (CME) associated with a filament eruption
became visible on February 26 at 1448 UTC.\u00a0 Model analysis
determined this CME to be a miss ahead of the Sun\/Earth line.<\/p>\n
Unsettled to active levels are likely on February 28 to March 1 as a
Coronal Hole influence continues, and a glancing blow is possible
from a Coronal Mass Ejection that occurred on February 25.<\/p>\n
Solar activity is forecast to range from low to moderate levels
through March 22.<\/p>\n
Minor to Moderate activity (R1 to R2) is possible at different
points throughout the period as active regions grow, evolve, and
return from the far-side of the Sun. There is a slight chance for R3
(Major) or greater events if any of the active regions develop
additional complex magnetic structures.<\/p>\n
Geomagnetic field activity is expected to be at quiet to unsettled
levels until March 6 with periodic, weak Coronal Hole influences.
Unsettled to active levels, with isolated G1 (Minor) storming
conditions are likely from March 7 to 18 as recurrent negative
polarity Coronal Holes are expected to be in a geoeffective
position.<\/p>\n
NOAA Space Weather forecasts a 55% chance of a Class-M flare, and a
10% chance of a Class-X flare, both within the next 48 hours
(February 28 to March 1).<\/p>\n
Weekly Commentary on the Sun, the Magnetosphere, and the Earth’s
Ionosphere – February 27, 2025, by F. K. Janda, OK1HH:<\/p>\n
“Solar activity is now increasing, but the increase is irregular,
which causes, among other things, a decrease in the reliability of
forecasts. Geomagnetically quiet periods, especially when associated
with an increase in total solar activity (such as 20-23 February),
are accompanied by improved conditions for ionospheric radio wave
propagation. A subsequent disturbance can cause even further
improvement (which happened on 24 February).<\/p>\n
“Following the increase in solar flare activity (from 23 February),
two proton flares were observed on 24 February. In the following
days, the Earth’s ionosphere was under the influence of a
solar-derived proton rain, after which the density of free electrons
in it decreased due to recombination.<\/p>\n
“However, the worsening of conditions was only noticeable on 25
February. The very next day, 26 February, there was an improvement,
in particular an increase in the MUF on a global scale. The jump in
the solar wind speed also contributed. However, the changes were so
rapid, even within a single day, that our assessment of the level of
conditions could have been reversed, depending on the time of day
and the frequency bands used.<\/p>\n
“The developments described can be considered as a harbinger of a
March increase in solar activity. Since the Spring Equinox is
approaching, it will contribute to an improvement in ionospheric
shortwave propagation, more accurately called decameter waves. The
possible shorter worse spells on March 1-2 and March 5-6 will make
no difference, with the seasonal improvement not fully manifesting
itself until the second half of the month.”<\/p>\n
This weekend is the ARRL International DX SSB contest.\u00a0 Information
can be found at, .<\/p>\n
For more information concerning shortwave radio propagation, see
and the ARRL Technical Information
Service web page at, For
an explanation of numbers used in this bulletin, see
. Information and
tutorials on propagation can be found at, .<\/p>\n
Also, check this:<\/p>\n
https:\/\/bit.ly\/3Rc8Njt<\/p>\n
“Understanding Solar Indices<\/em>” from September 2002 QST<\/em>.<\/p>\n The predicted 10.7 cm flux for February 28 to March 6 is 195, 195, \u00a0<\/p>\n<\/p><\/div>\n
190, 190, 190, 190, and 185, with a mean of 190.7.\u00a0 The predicted
Planetary A Index for February 28 to March 6 is 12, 10, 8, 5, 5, 5,
and 5, with a mean of 7.1.\u00a0 The predicted K Index for February 28 to
March 6 is 4, 3, 3, 2, 2, 2, and 2, with a mean of 2.6.<\/p>\n