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000
FXXX12 KWNP 200031
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Apr 20 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 reached moderate levels this period. Region 3647 (S13W00,
Dac/beta-delta) produced two M-flares (R1/Minor), the largest of which
was an M2.1 flare at 19/0453 UTC. Region 3647 began to show signs of
separation of the shared penumbra between its principle spots. Region
3645 (S09W04, Dai/beta) underwent slight decay in its intermediate spot
area and consolidation of the leader and trailing spots. Region 3639
(N29W02, Ekc/beta-gamma) underwent some slight area growth. New Regions
3649 (N16W24, Bxi/beta), 3650 (S11E21, Cro/beta) and 3651 (N13E25,
Bxo/beta) were numbered, but were otherwise unremarkable.

Other activity included a large prominence eruption on the SE limb
beginning at around 19/0400 UTC, however, the associated CME is not
Earth-directed. No Earth-directed CMEs were detected in available data.

.Forecast...
Solar activity is expected to reach moderate levels on 19-21 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 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 became enhanced beginning at 19/0413 UTC due to
CME activity. Following CME arrival, total field strength reached 18 nT
and the Bz component was sustained southward after 19/0410 UTC with a
peak of -17 nT observed. Solar wind speeds reached up to ~549 km/s at
19/2233 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) geomagnetic storm levels this
period in response to CME activity.

.Forecast...
Periods of unsettled to active levels are expected on 20-21 Apr due to
continued CME activity, coupled with the onset of negative polarity CH
HSS influences and the anticipated arrival of multiple CMEs from 16-18
Apr. Quiet to unsettled conditions are expected on 22 Apr due to
negative polarity CH HSS influence.