152
FXXX12 KWNP 011231
DAYDIS

:Product: Forecast Discussion
:Issued: 2026 Jun 01 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
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#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity remained at low levels with weak C-class flare activity.
Region 4446 (S14W43, Cso/beta) continued to undergo decay while
producing low level C-class flare activity. Region 4455 (N15E17,
Cko/beta) exhibited decay while its large leading penumbra began to take
on an asymmetric shape. Region 4456 (N14, L=66) decayed to plage.

Two CMEs of note were observed during the period. The first was seen
emerging from the southwest in GOES CCOR-1 imagery at approximately
31/1330 UTC. Analysis of GOES SUVI imagery determined the bulk of the
material associated with this event to have originated from beyond the
western limb and thus is not Earth-directed. However, it should be noted
that relatively narrow, jet-like ejecta from the vicinity of AR 4446 and
AR 4449 (S08W38, Hsx/alpha) was observed in GOES SUVI 304 imagery as
well just before the larger far side eruption and could have been faint
enough to have been masked. The second CME of note was observed emerging
from the southwest as well in GOES CCOR-1 imagery near 31/1715 UTC. SUVI
304 angstroms indicated a likely source location of AR 4447. There is
currently a gap in LASCO C2 coronagraph imagery that would be needed to
perform modeling of this event as of the time of this writing, but an
Earth-directed component can reasonably be ruled out based upon source
location alone.

.Forecast...
Solar activity is expected to be at low to moderate levels through 02
Jun with a chance for isolated M-class flare activity. M-class flare
probabilities decrease to a slight chance (20%) on 03 Jun as multiple
regions exit the western limb.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit was at low
to moderate levels. The greater than 10 MeV proton flux at
geosynchronous orbit remained at background levels.

.Forecast...
The greater than 2 MeV electron flux is expected to continue to reach
moderate levels through 03 Jun with a chance for high levels. The
greater than 10 MeV proton flux is expected to remain at background
levels through 02 Jun.

Solar Wind

.24 hr Summary...
Solar wind parameters reflected negative polarity CH HSS influences.
Total field primarily ranged 3-7 nT. The Bz component of the IMF began
the period with brief deflections reaching -3 nT, and remained weakly
southward. Solar wind speeds began the period near 550 km/s, but slowly
decayed to near 425 km/s by periods end.

.Forecast...
Negative polarity CH HSS influences are expected to continue through 01
Jun with possible glancing influences from the slow eruptions that
departed the Sun on 27 and 28 May. Ambient-like conditions are expected
to return by the close of 02 Jun. Enhanced conditions are anticipated to
return on 03 Jun first due to a solar sector boundary crossing followed
by weak and likely glancing CME influences from an eruption that left
the Sun on 30 May.

Geospace

.24 hr Summary...
The geomagnetic field oscillated between quiet to isolated unsettled
levels.

.Forecast...
Unsettled to isolated active conditions are expected for the remainder
of 01 Jun under continued negative polarity CH HSS effects and any
glancing influences from the 27 and 28 May CMEs. Mostly quiet
conditions, with isolated unsettled periods, are expected to prevail on
02 Jun as CH HSS effects wane. Unsettled to active levels, with a chance
for G1 (Minor) storming periods, are expected to return on 03 Jun due to
combined solar sector boundary crossing and relatively weak, glancing
CME effects from the aforementioned 30 May event.