= NOW 18 WPM transition file follows =

Solar activity is expected to range from low to moderate levels
through March 15.  There is a varying chance for R1 or R2, Minor or
Moderate, events, and a slight chance for R3 or greater events.
Geomagnetic field activity is likely to reach G1, or Minor, levels
on February 28, March 9, and March 12 to 14.  Active levels are
predicted for March 1. Quiet, and quiet to unsettled conditions are
expected to prevail throughout the remainder of the period.  The
NOAA Ap Index Forecast is 5 for February 21 and 22.  The NOAA Space
Weather Prediction Center reports no space weather storms predicted
for the next 24 hours.  For the last 24 hours, solar flare activity
has been at low levels with only a C Class observed.  The largest
flare was a C8.1 on February 19.  This flare was accompanied by a
Type II radio emission and associated CME off the Southwest edge of
the solar disk. Modelling efforts determined the bulk of the CME to
miss ahead of Earths orbit.  However, a weak glancing influence
cannot be ruled out late on February 24.  Region AR3996 is the
largest and most complex region on the disk but was responsible for
only one C Class flare. Flux emergence and an increase in interior
spots can be seen in Region AR3998 but overall the region has been
fairly quiet.  Spaceweather.com has an article link from the
Advancing Earth And Space Sciences website concerning an extreme
compression of Earths magnetic field that was caused by the May 2024
solar superstorm.  Weekly Commentary on the Sun, the Magnetosphere,
and the Earths Ionosphere, February 20, 2025, by F. K. Janda, OK1HH,
The increase in geomagnetic activity following the decrease in solar
activity is a simple phenomenon to explain systems of magnetic field
lines over active regions in the Sun open up and charged particles,
both free electrons and the nuclei of hydrogen atoms, or protons
themselves, slip through them more easily into space.  In Earths
orbit, we see an increase in the solar wind and, consequently, an
increase in geomagnetic activity. At the same time, the ionization
rate of the ionosphere is increasing, while the shortwave
propagation conditions may not only worsen, due to scattering on
inhomogeneities, but also improve as the MUF may grow.  This was
well known, for example, on Saturday 15 February on the Europe/North
America route.  The only geomagnetically quiet days in the first
half of the month were 3 to 7 February. Then the solar wind, blowing
from the long canyon shaped coronal hole, intensified and
geomagnetic activity was elevated for most of the second third of
February. A calm trend can be expected on most days of the last
third of the month. Although there does not appear to be a
significant increase in solar activity, it is sufficiently high. In
addition, spring is approaching, which is good news for the state of
the ionosphere.  The predicted Planetary A Index is 5 for February
21 to 26, and 10 on February 27.  The predicted Planetary K Index is
2 on February 22 to 26, and 3 on February 27.  Predicted 10.7 cm
solar flux is 170 for February 22 to 23, 190 on February 24, 195 on
February 25, 200 on February 26, and 195 on February 27.

= END OF 18 WPM transition file <