12th March

Solar activity reached high levels during the period. At approximately
11/1622 UTC, Region 2297 (S16W00, Dkc/beta-gamma-delta) produced an
impulsive X2/2b flare with associated Type II (est. shock speed 1461
km/s) and Type IV radio emissions, as well as a 160 sfu Tenflare.
SDO/AIA imagery observed ejecta leaving the flare location in a mostly
easterly direction. This region also produced an M1/1n flare at 11/1851
UTC and an M3 flare at 12/0446 UTC. Numerous mid to upper-level C-class
flares were also observed from this region over the past 24 hours.

Region 2299 (S07E53, Bxo/beta) rotated onto the East limb and was
numbered during the period. This new region produced a C7 flare at
12/0218 UTC with an associated Type II radio sweep (est. shock speed
1903 km/s). No LASCO coronagraph imagery is available. However, based on
the location of the spot group, any associated coronal mass ejection
(CME) that may originate from this area will likely be too far East of
the Sun-Earth line. Region 2298 (S11W52, Cro/beta) continued to develop
slightly but remained quiescent.

Due to an extended outage of SOHO LASCO coronagraph imagery, accurate
analysis of any CMEs associated with the X2, M1, and M3 flares is
degraded, at best. However, the presence of the Type II radio sweep
combined with SDO/AIA 304 imagery indicated there was likely a CME
associated with the X2 flare with at least a portion of the plasma cloud
directed at Earth.

Solar activity is expected to be at low levels with M-class
(R1-R2/Minor-Moderate) flare activity likely for the next three days
(12-14 Mar). A slight chance for X-class (R3 or greater) flare activity
still exists as Region 2297 maintains its size and complex magnetic
structure. The forecast remains unchanged for the CMEs previously
mentioned in the prior discussion as it appears that a combined impact
of these transients may occur in the form of a glancing blow, mid to
late on day two (12 Mar).

A very rough estimate, based solely on the Type II estimated shock speed
and available SDO imagery, indicate the approximate arrival time of the
CME associated with the X2 flare at Earth is mid to late in the day on
13 March, prompting possible increases in solar wind velocities as the
transient passes Earth.

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