:Product: Weekly Highlights and Forecasts
:Issued: 2014 Jan 13 0717 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
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
06 - 12 January 2014

Solar activity ranged from low to high levels during the period. Low
levels were observed on 06 January and again from 09-12 January with
the majority of the solar flare activity originating from Regions
1944 (S09, L=101, class/area Fkc/1560 on 08 January), 1946 (N09,
L=103, class/area Dkc/530 on 10 January), and 1947 (N11, L=180,
class/area Cro/030 on 06 January). High levels were reached on 07
January due to an M1/1n flare at 07/0353 UTC from Region 1946, an
M7/2b flare at 07/1013 UTC with an associated Tenflare (Castelli-U)
radio burst (409 sfu) from Region 1944, and an X1/2n at 07/1832 UTC
also from Region 1944. The X1 flare was associated with a Type II
radio sweep (1064 km/s), a 8300 sfu Tenflare, and a partial halo
coronal mass ejection (CME) with an approximate speed ranging from
1800 km/s to 2100 km/s. Model output of the CME indicated an
Earth-directed component; however the impact on the geomagnetic
field was significantly less than expected (see geomagnetic field
activity below). By 08 January, solar activity decreased to moderate
levels due to an isolated M3/Sf flare from Region 1947 at 08/0347
UTC on the west limb. The M3 flare was accompanied by a Type II
radio sweep (697 km/s) and a non-Earth directed CME. Region 1944 was
one of the largest sunspot groups in solar cycle 24, maintained a
Fkc spot class with a complex beta-gamma-delta magnetic
classification for the majority of the period, as well as reaching
an impressive 1,560 millionths of areal coverage. By 09 January and
through the rest of the reporting period the sunspot group was in a
slow decay phase.

The period began with the greater than 10 MeV proton flux recovering
from last weeks enhancement likely associated with an M4 flare from
Region 1944 late on 04 January. At 06/0820 UTC, both the greater
than 10 MeV and 100 MeV proton flux levels began to rise in response
to flare activity beyond the west limb from old Region 1936 (S15,
L=225) which rotated off the visible disk on 04 January. The greater
than 10 MeV protons crossed the 10 pfu (S1 Minor) threshold at
06/0915 UTC and reached a maximum of 42 pfu at 06/1600 UTC before
slowly declining to 10.1 pfu by 07/1930 UTC. The greater than 100
MeV protons crossed the 1 pfu threshold at 06/0830 UTC and reached a
maximum of 4 pfu at 06/1005 UTC. The event ended at 06/1710 UTC. By
07/1935 UTC, another influx of energetic particles was observed by
GOES 13 related to the X1 flare from Region 1944 at 07/1832 UTC. The
10 MeV proton flux levels were still above the 10 pfu threshold at
this time and increased to a maximum of 1033 pfu (S3-Moderate) at
09/0340 UTC before slowly returning below the 10 pfu threshold by
11/2020 UTC. However, there were some fluctuations in the greater
than 10 MeV protons early on 12 January with a couple readings above
the 10 pfu threshold. The greater than 100 MeV proton event
associated with the X-flare reached the 1 pfu threshold at 07/2030
UTC, reached a maximum of 4 pfu at 07/2240 UTC, and ended at 08/1225
UTC.

The greater than 2 MeV electron flux at geosynchronous orbit was at
mostly normal to moderate levels during the period with high levels
(2690 pfu) briefly reached on 07 January before the instrument
became contaminated due to high proton flux levels late on 07
January through 09 January. By 10 January, electron flux levels
recovered and remained in the normal to moderate range for the rest
of the period.

Geomagnetic field activity ranged from quiet to active levels during
the period. The geomagnetic field began the period at quiet levels
until after mid-day 07 January when a sudden increase in
temperature, speed, density, and total field measurements were
observed in ACE SWEPAM data indicating the arrival of the 04 January
CME. Solar wind speed increased from approximately 350 km/s to 435
km/s with the total field increasing from 3 nT to 7 nT at 07/1428
UTC. This small shock and CME resulted in several periods of
unsettled levels late on 07 January through early on 08 January.
Quiet to unsettled levels continued through 09 January. Late on 09
January, the anticipated arrival of the CME associated with the X1
flare on 07 January arrived at the ACE spacecraft at 09/1932 UTC
with a less than expected solar wind increase of from approximately
400 km/s to near 527 km/s. Total field measurements increased from 6
nT to 16 nT with the Bz component mostly north between -4 nT and +10
nT. A small sudden impulse (12 nT) was observed in the Fresno
magnetometer data at 09/2010 UTC. An isolated unsettled period was
observed late on 09 January as a result of CME activity. Nominal
solar wind condition continued through late on 12 January with
mostly quiet conditions observed. By late on 12 January, a negative
polarity coronal hole high speed stream (CH HSS) began to impact the
geomagnetic field. Solar wind speeds increased from approximately
480 km/s to near 680 km/s by the end of the period. The geomagnetic
field responded with unsettled to active levels by late on 12
January.

Forecast of Solar and Geomagnetic Activity
13 January - 08 February 2014

Solar activity is expected to be at low levels with a chance for
M-class flare activity until Region 1944 rotates off the west limb
on 14 January. Very low to low levels are expected from 15-16
January. Low levels with a chance for M-class flare activity is
expected from 17 January through 08 February as old Regions 1936 and
1944 return on 17 January and 26 January, respectively.

There is a chance for a greater than 10 MeV proton event from 26
January through 08 February when Region 1944 returns on the visible
disk assuming it retains its magnetic complexity.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal to moderate levels with high levels
possible from 14-17 January, 29 January, and 03-05 February due to
CH HSS activity and recurrence.

Geomagnetic field activity is expected to be mostly quiet with
unsettled to active period possible on 13 January, 23-24 January,
28-30 January, and again on 07-08 February due to recurrent CH HSS
activity.