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000
FXXX12 KWNP 201231
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Apr 20 1230 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 reached moderate levels due to an isolated M1.0 flare at
19/1306 UTC from Region 3647 (S13W08, Dac/beta-delta), which continued
to show signs of separation of the shared penumbra between its principle
spots. Region 3645 (S09W13, Dai/beta) underwent slight decay in its
intermediate spot area and consolidation of the leader and trailing
spots. Minor growth was observed in Region 3650 (S11E14, Cao/beta) while
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 20-22 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 Particle

.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 20-22 Apr. There is a slight chance for the
greater than 10 MeV proton flux to exceed S1 (Minor) storm levels over
20-22 Apr due to the flare potential of several active regions on the
visible disk.

Solar Wind

.24 hr Summary...
Solar wind conditions were enhanced this period following the passage of
a CME early on 19 Apr. Total field strength reached 18 nT and the Bz
component was sustained southward until 19/1830 UTC with a peak of -17
nT observed. Solar wind speeds reached a peak of 549 km/s at 19/2235
UTC.

.Forecast...
Enhanced solar wind conditions are expected to prevail over 20-22 Apr
due to CME activity (on 20 and 21 Apr) and negative polarity CH HSS
influences (on 20-22 Apr).

Geospace

.24 hr Summary...
The geomagnetic field reached G3 (Strong) storm levels this period
following the passage of a CME early on 19 Apr.

.Forecast...
Geomagnetic field activity is expected to be quiet and unsettled on 20
Apr with waning CME effects and the onset of negative polarity CH HSS
influences. Periods of active conditions are expected on 21 Apr 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
with waning CH HSS influences.