Weekly Highlights of Solar and Geomagnetic Activity, 05 - 11 November 2012

[SWPC.We...@noaa.gov]

:Product: Weekly Highlights and Forecasts
:Issued: 2012 Nov 12 0405 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/weekly.html
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# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
05 - 11 November 2012

Solar activity ranged from very low to moderate levels. On 05
November, low levels were observed due to a C2 X-ray flare from a
unnumbered region around the southeast limb at 05/1839 UTC. Solar
activity remained at very low levels until 08 November when a long
duration M1 flare was observed at 08/0223 UTC from Region 1611 (N13,
L=240, class/area Eso/270 on 09 November). Associated with this
event was a Type II radio sweep (784 km/s) and a non-geoeffective
coronal mass ejection (CME) off the East limb. Also on 08 November,
a full halo backsided CME was observed in SOHO/LASCO imagery from
old Region 1598 (S12, L=111). By 09 November, solar activity
returned to low levels with a single C1 flare from Region 1604 (N08,
L=322, class/area Bx0/010 on 03 November) at 09/0151 UTC. Also on 09
November, a 12 degree long filament, centered near S16E03, erupted
at approximately 09/1230 UTC which resulted in an Earth-directed CME
first observed in SOHO/LASCO C2 imagery at 09/1524 UTC. By 10
November, multiple low level C-flares were observed including a long
duration C2 flare from Region 1608 (S20, L=286, class/area Hrx/020
on 06 November) at 10/0504 UTC. An Earth-directed CME was observed
in association with this C2 flare in STEREO A COR2 imagery at
10/0539 UTC and SOHO/LASCO C3 imagery at 10/1054 UTC. By 11
November, solar activity increased to moderate levels due to an M1
flare from Region 1614 (N15, L=193, class/area Dso/110 on 11
November) at 11/0233 UTC with an associated Type II radio sweep (659
km/s).

An enhancement of the greater than 10 MeV proton flux at
geosynchronous orbit was observed beginning at approximately 08/1400
UTC likely associated with flare activity and the associated CME
from old Region 1598. A peak enhancement of 2.4 pfu was observed at
09/0420 UTC and remained slightly enhanced through the end of the
reporting period. No event thresholds were exceeded.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal background levels throughout the reporting period.

Geomagnetic field activity was at quiet levels until 07 November
when a coronal hole high speed stream (CH HSS) moved into
geoeffective position. At 06/2119 UTC, the phi component of the
interplanetary magnetic field changed from positive to negative with
corresponding increases in density, temperature, and speed in ACE
spacecraft data indicating a solar sector boundary crossing followed
by a co-rotating interaction region and CH HSS. Solar wind speed
increased from approximately 300 km/s to a peak of near 525 km/s by
07/1538 UTC. Total field (Bt) reached a maximum of 14 nT at 07/0031
UTC with a maximum deflection of the Bz component southward to -12
nT at 07/0039 UTC. The geomagnetic field responded with quiet to
active periods on 07 November. By 08 November, conditions returned
to quiet levels and remained that way through the end of the
reporting period.

Forecast of Solar and Geomagnetic Activity
12 November - 08 December 2012

Solar activity is expected to be low with a chance for M-class
flares through 24 November when Region 1614 is due to rotate off the
west limb. Very low to low conditions are expected from 12 November
until 27 November. On 28 November, and through the end of the
forecast period, very low to low conditions with a chance for
M-class activity is expected with the return of old Region 1598.

There is a slight chance for a greater than 10 MeV proton event from
28 November through the end of the reporting period due possible
flare activity from old Region 1598.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal levels on 12 November. Moderate to high
levels are expected from 13-24 November due to CME activity and
recurrence. Normal levels are expected from 25 November through 03
December. Moderate to high levels are expected from 04-06 December
due to CH HSS activity. By 07 December through the end of the
forecast period, normal levels are expected.

Geomagnetic field activity is expected to be unsettled to active
with a chance for minor storm periods starting around mid-day on 12
November and continuing through 13 November as the 09 and 10
November CMEs are expected to become geoeffective. Unsettled levels
are expected on 14 November as CME activity wanes. Mostly quiet
conditions are expected from 15-18 November. Quiet to unsettled
conditions are possible on 19 November due to a possible solar
sector boundary crossing. From 20 November through 02 December,
mostly quiet conditions are expected. On 03-04 December, a recurrent
CH HSS is expected to become geoeffective causing quiet to unsettled
with isolated active conditions. A return to mostly quiet conditions
is expected from 05 December through the end of the forecast period.