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000
FXXX12 KWNP 210031
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Apr 21 0030 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity is currently low with C-class flare activity observed
from Regions 3636 (S21W44, Cro/beta), 3638 (S18W22, Cai/beta), 3639
(N29W14, Eac/beta-gamma), 3643 (S13W03, Cro/beta) and 3645 (S09W20,
Dai/beta), the largest region on the disk .The largest flare was a C7.5
at 20/1706 UTC from Region 3645. The next largest spot group, Region
3647 (S13W15, Dac/beta-delta), was quiet this period, and continued to
show signs of separation of the shared penumbra between its principle
spots. Regions 3644 (N13E23, Dao/beta), 3645 and 3650 (S11E05, Cai/beta)
displayed slight area growth. The remaining regions were stable or in
decay. No Earth-directed CMEs were detected in available coronagraph
imagery.

.Forecast...
Solar activity is expected to reach moderate levels on 21-23 Apr.
M-class flares (R1-R2/Minor-Moderate) are expected, with a slight chance
for X-class flares (R3/Strong), due to the flare potential of several
active regions on the visible disk.

Energetic Particles

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to moderate levels
and the greater than 10 MeV proton flux was steady at background levels.

.Forecast...
The greater than 2 MeV electron flux is expected to continue at normal
to moderate levels over 21-23 Apr. There is a slight chance for the
greater than 10 MeV proton flux to exceed S1 (Minor) storm levels over
21-23 Apr due to the flare potential of several active regions on the
visible disk.

Solar Wind

.24 hr Summary...
Solar wind conditions were enhanced early this period following the
passage of a CME early on 19 Apr. Total field strength reached 7 nT and
the Bz component was sustained southward most of the period with a peak
of -6 nT observed. Solar wind speeds reached a peak of 5433km/s at
20/0408 UTC. By periods end, wind speeds were in the 400-450 km/s
range. Phi angle was mostly variable through the period.

.Forecast...
Enhanced solar wind conditions are expected to prevail over 21-23 Apr
due to CME activity (on 21 Apr) and negative polarity CH HSS influences
(on 21-23 Apr).

Geospace

.24 hr Summary...
The geomagnetic field was at quiet to unsettled levels under waning
effects from the CME early on 19 Apr.

.Forecast...
Geomagnetic field activity is expected to be at unsettled to active
levels on 21 Apr quiet due to continued CH HSS influences and the
anticipated arrival of multiple CMEs from 16-18 Apr. Quiet and unsettled
conditions are expected on 22 Apr, increasing to unsettled to active
levels with negative polarity CH HSS influences.