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000
FXXX12 KWNP 171231
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Apr 17 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 M1.1 flare at 16/1802
UTC from newly numbered Region 3645 (S10E31, Cai/beta). Although
previously reported as originating from Region 3643, looking at previous
imagery of the development of the spot group, it was determined to be a
separate region. Region 3645 exhibited slight growth over the period, as
well as Regions 3643 (S13E41, Dai/beta) and 3638 (S17E21, Cri/beta).
Consolidation was observed in Region 3634 (N27W63, Dki/beta) while
Region 3639 (N29E29, Eki/beta-gamma-delta) appeared to be separating. A
new region rotated around the NE limb and was numbered as 3646 (N21E66,
Hrx/alpha). The rest of the spot groups were either stable or slightly
decaying.

An approximate 15 degree filament eruption was observed after 16/1900
UTC centered near S45E30. An associated CME was observed off the S limb
at 16/2124 UTC. Analysis indicated the potential for a grazing early to
midday on 21 Apr. Another filament eruption was observed at 17/0100 UTC
in H-alpha imagery. The approximate 20 degree filament structure was
centered near N40W00. An associated CME was observed off the NW limb at
17/0506 UTC in SOHO/LASCO C3 imagery. Initial analysis indicated no
Earth-directed component.

.Forecast...
Solar activity is forecast to be moderate, with M-class flares
(R1-R2/Minor-Moderate) likely and a slight chance for an X-class flare
(R3/Strong) over 17-19 Apr.

Energetic Particle

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

.Forecast...
There is a slight chance for a greater than 10 MeV proton event
(S1/Minor) over 17-19 Apr. The greater than 2 MeV electron flux is
expected to continue at normal to moderate levels through 19 Apr.

Solar Wind

.24 hr Summary...
Solar wind parameters continued to be enhanced under CME influence.
Although solar wind speed was nominal in the 341-422 km/s range, total
field values reached 13 nT with a prolonged period of southward Bz
between 16/1205-2231 UTC.

.Forecast...
Solar wind conditions are expected to trend towards nominal levels
mid-day to late on 17 Apr. Early on 18 Apr, additional enhancements are
expected due to the anticipated arrival of CMEs that left the Sun on 14
and 15 Apr. Waning CME conditions are likely on 19 Apr.

Geospace

.24 hr Summary...
The geomagnetic field ranged from quiet to G1 (Minor) levels under
CME influence.

.Forecast...
The geomagnetic field is expected to be at quiet to unsettled levels for
the rest of the UTC day on 17 Apr. G1 (Minor) geomagnetic storm
conditions are likely on 18 Apr due to anticipated arrival of CMEs that
left the Sun on 14 and 15 Apr. Quiet to unsettled conditions are likely
over 19 Apr as CME influence wanes.