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000
FXXX12 KWNP 191231
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Apr 19 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 this period. Region 3647 (S13E07,
Dac/beta-delta) produced three 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 (S09E03, Dai/beta) underwent slight decay in its intermediate spot
area and consolidation of the leader and trailing spots. Region 3639
(N29E05, Eai/beta-gamma) slowly decayed throughout the period. New
Regions 3649 (N16W17, Bxi/beta) and 3650 (S11E28, Cro/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 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 19-21 Apr. There is a slight chance for the
greater than 10 MeV proton flux to exceed S1 (Minor) storm levels over
19-21 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 16 nT
and the Bz component was sustained southward after 19/0410 with a peak
of -14 nT observed. Solar wind speeds reached a peak of 439 km/s at
19/1050 UTC.

.Forecast...
Enhanced solar wind conditions are expected to prevail over 19-21 Apr
due to CME activity (on 19 and 21 Apr) and negative polarity CH HSS
influences (on 20-21 Apr).

Geospace

.24 hr Summary...
The geomagnetic field reached active levels this period in response to
CME activity.

.Forecast...
Periods of active conditions and G1 (Minor) storms are expected on 19
Apr due to continued CME activity. Quiet and unsettled conditions are
expected on 20 Apr due to waning CME effects followed by the onset of
negative polarity CH HSS influences. Periods of active conditions are
likely again on 21 Apr due to continued negative polarity CH HSS
influences and the anticipated arrival of multiple CMEs from 16-18 Apr.