Message:23222 In: SPACWX.USA
From: N4SDDate: Fri, 29 May 26 00:32:00 Z
Newsgroups: SPACWX.USA
Subject: Space Weather Forecast Discussion
Message-ID: <14546_N4SD>
Path: N2MH4|N3MEL|KC3SMW|N3IP|KA3VSP|N4SD
R:260529/0547Z 31753@N2MH4.#SENC.NC.USA.NOAM LinBPQ6.0.24
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FXXX12 KWNP 290031
DAYDIS
:Product: Forecast Discussion
:Issued: 2026 May 29 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 remained at low levels. The largest event of the period
was a C3.2/Sf flare at 28/0729 UTC from Region 4452 (N09W34, Dai/beta).
There are eleven numbered regions on the visible disk. Region 4452
underwent rapid growth with notable new flux emergence, developing a
complex gamma configuration. Region 4452 is also notable as it is an
anti-Hale region with reversed magnetic polarity for its hemisphere in
Solar Cycle 25. Region 4449 (S10E11, Cao/beta) showed minor new flux
emergence with opposite polarity transitory spots appearing, making it
no longer a unipolar group while its main leading spot declined in
extent. Region 4455 (N15E65, Dho/beta) continues to rotate onto the disk
as an apparently stable D-group, though limb foreshortening hinders full
characterization. The remaining regions on the visible disk remained
stable or displayed minor decay and simplification.
A fair amount of faint eruptive activity was noted from the cluster of
active regions in the southeast, though a lack of distinct flares or
major on-disk signatures complicates source identification. At least two
very faint CMEs were observed: a narrow CME first visible in LASCO C2 at
approximately 27/2300 UTC (and CCOR1 at 28/0045 UTC), and a secondary
faint CME first seen in STEREO-A COR2 imagery at 28/0938 UTC. Both
events were preceded by faint coronal dimming in the southeast as seen
in GOES SUVI imagery. No other Earth-directed CMEs were observed in
available coronagraph imagery.
.Forecast...
Solar activity is expected to be at low to moderate levels through 31
May. There remains a chance for isolated M-class flares
(R1-R2/Minor-Moderate), driven primarily by Regions 4452 and 4455.
Energetic Particle
.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit was at low
to moderate levels, with a peak flux of 561 pfu observed at 28/1720 UTC.
The greater than 10 MeV proton flux at geosynchronous orbit began the
period slightly elevated but gradually declined back to baseline
background levels by the end of the period following the 26 May S1
(Minor) solar radiation storm.
.Forecast...
The greater than 2 MeV electron flux is expected to remain at low to
moderate levels through 31 May, as anticipated enhancements are not
anticipated to be sufficient to raise flux levels. The greater than 10
MeV proton flux is expected to remain at background levels.
Solar Wind
.24 hr Summary...
The solar wind environment was indicative of mild negative polarity
coronal hole high-speed stream (-CH HSS) influences. Total magnetic
field (Bt) strength ranged primarily from 6 to 10 nT, and the
north-south (Bz) component was highly variable between northern and
southern orientations, with a peak southward deflection to -8 nT. The
phi angle was predominantly in a negative (towards the Sun) sector.
Solar wind speed ranged mainly between 350-400 km/s for most of the
period, with a brief increase to approximately 450 km/s observed later
in the timeframe.
.Forecast...
Mild enhancements due to weak -CH HSS influences will persist through 29
May. Further enhancements are possible on 30 May due to a CME that
departed the Sun on 26 May. Additional solar wind enhancements are
anticipated on 31 May due to the onset of a new -CH HSS, combined with
possible glancing influences from the slow eruptions that departed the
Sun on 27 and 28 May.
Geospace
.24 hr Summary...
The geomagnetic field was quiet to active in varying response to -CH HSS
influences.
.Forecast...
Geomagnetic field conditions are anticipated to be at quiet to unsettled
levels 29–30 May, with a chance for isolated active periods due to
waning -CH HSS effects and potential glancing CME influences. Active
conditions are likely on 31 May in response to the combined onset of the
new -CH HSS and glancing CME influences.
------
73 de Sperry N4SD
N4SD@N4SD.#TIDE.VA.USA.NOAM
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