9th September


Solar activity was at moderate (NOAA Scale R1-minor) levels due to a
long-duration M4/1n flare at 09/0029 UTC from Region 2158 (N15E21,
Dkc/beta-gamma-delta). This flare was originally believed to be from
Region 2157 (S15E13, Ekc/beta-gamma-delta), but after additional imagery
became available, was later determined to be from Region 2158. The M4/1n
flare had associated Type II (999 km/s estimated shock velocity) and
Type IV radio sweeps, as well as a 10cm (370 sfu) radio burst.

The associated asymmetrical, full halo coronal mass ejection (CME),
first observed in Lasco C2 imagery at 09/0006 UTC, appears to be
directed mostly northeastward, with the bulk of the ejecta well east of
the sun/Earth line. It does appear, however, that Earth may see a
glancing blow shortly after this forecast period ends.

Region 2157 and Region 2158 remain the largest and most complex regions
on the visible disk. Region 2157 exhibited minor consolidation in its
leader spots with slight development in its southern most intermediate
spots. Region 2158 had minor spot development just north and slightly
south of the large leader spot, and maintained its enhanced magnetic
complexity. Region 2155 (S21W01, Cao/beta) exhibited minor spot growth
in the smaller leader spots, but was otherwise fairly stable. The other
regions on the visible disk remained relatively unchanged.

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