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000
FXXX12 KWNP 161231
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Apr 16 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. Region 3639 (N28E43,
Eai/beta-gamma) produced multiple M-class flares. The largest was an
M4.0 (R1-Minor) flare at 15/1932 UTC. Development and growth was
observed in Region 3639, Region 3643 (S13E55, Dai/beta), Region 3638
(S17E39, Cao/beta), Region 3637 (S13E34, Bxo/beta), and Region 3634
(N26W49, Dhi/beta). Low-level M-class (R1) activity was also observed
from Region 3634. The remaining regions were either stable or in decay.

The faint CME observed off the NE limb at 14/1124 UTC in SOHO/LASCO C2
imagery, likely associated with a long duration C5.0 flare from Region
3636 (S18E20, Cso/beta) at 14/1101 UTC, was analyzed. Another faint
partial halo CME was observed at 15/0648 UTC, likely associated with a
filament eruption N of Region 3636 at 15/0557 UTC.  Analysis of these
events suggests a combined Earth-directed component late on 17 through
18 Apr.

.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 16-18 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 16-18 Apr. The greater than 2 MeV electron flux is
expected to continue at normal to moderate levels through 18 Apr.

Solar Wind

.24 hr Summary...
Solar wind parameters became weakly enhanced after 15/1725 UTC and
suggested the arrival of a CME that left the Sun on 12 Apr. Total
magnetic field strength increased from 5 nT to a peak of 12 nT. The Bz
component reached as far southward as -10 nT. Solar wind speeds only
increased from ~330 km/s to between 375-415 km/s. Phi angle was mostly
negative.

.Forecast...
Solar wind conditions are expected to continue at enhanced levels on 16
Apr. Late on 17 Apr and into 18 Apr, additional enhancements are
expected due to the anticipated arrival CMEs that left the Sun on 14 and
15 Apr.

Geospace

.24 hr Summary...
The geomagnetic field ranged from quiet to active levels under CME
influence.

.Forecast...
The geomagnetic field is expected continue at unsettled to active levels
through 16 Apr due to the passage of a CME from 12 Apr. Additional
unsettled to active conditions are expected over on 17-18 Apr, with G1
(Minor) storming likely on 18 Apr, due to the anticipated influence of
CMEs that left the Sun on 14 and 15 Apr.