Routine Space Environment Product Issued Weekly
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:Product: 7-day Space Weather Highlights
:Issued: 2014 Apr 14 0224 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
#
#                7-day Space Weather Highlights
#
Highlights of Solar and Geomagnetic Activity
07 - 13 April 2014

Solar activity was low. The largest flare of the week was a C9, with
no optical counterpart, produced by Region 2035 (S18, L=222,
class/area=Eai/210 on 13 Apr) on 11 Apr at 1124 UTC. The same region
produced a C5 flare at 11/1501 UTC. A small CME, most likely
associated with the C9 event, was visible in LASCO C2 coronagraph
imagery at 11/1212 UTC but was directed well south and east of the
ecliptic plane. A much larger CME associated with the C5 flare was
observed in LASCO C2 imagery at 11/1448 UTC. The CME was also on the
east limb and the majority of the ejecta was directed away from
Earth. Region 2035 began as a plage area on 09 Apr and by the 11th
had grown to a Dao Beta-type group with 2 spots. It developed a
beta-gamma magnetic configuration on the 12th.

In addition to CMEs associated with the week's largest flares,
others accompanied filament eruptions. A 9 degree filament eruption
was observed near S23E25 at 10/0004 UTC. An associated CME occurred
off the southeast limb with an estimated speed of 298 km/s. Around
the same time, Region 2031 (N03, L=30, class/area=Dao/50 on 08
April) produced a C1/Sf flare at 10/0013 UTC and a slow,
westward-directed coronal mass ejection (CME) with coronal dimming
visible in SDO/AIA imagery. Analysis suggested a speed near 330
km/s. A Type II radio sweep (1109 km/s) was also observed between
10/0010-0022 UTC . A 14 degree filament centered near S35W48
disappeared at 10/0622 UTC with no apparent CME in LASCO imagery.
Neither these CMEs, nor others occurring throughout the week, were
judged to be particularly geoeffective.

No proton events were observed at geosynchronous orbit, however, the
week began with slightly elevated flux levels (<1 pfu) in the
wake of an M6 flare the previous week. By 09 April, flux had
returned to background levels.

The greater than 2 MeV electron flux at geosynchronous orbit was
normal to moderate throughout the week.

Geomagnetic field activity began the week at unsettled to active
levels on 07 April attributed to the muted effects of transient
features. Activity remained at quiet levels from 08 April through
late on 11 April. Late on the 10th, around 1928 UTC, there was a
modest increase in solar wind speed from 350-400 km/s. The brief
episode of increased winds was followed by a jump in density and
accompanied by fluctuations in Phi angle. Over the next 36 hours,
Phi exhibited a smooth rotation from a positive to a negative
orientation. Bz began to plunge southward around 11/0940 UTC,
reaching a minimum of about -10 nT by 12/0800 UTC. Bt reached a
maximum near 12 nT by 12/1406 UTC. Throughout the 11th and 12th,
solar wind speed continued to decline, reaching a minimum of 316
km/s at 12/1331 UTC. The planetary geomagnetic field responded to
the nearly 24 hours of southward Bz with minor storm conditions
(Kp=5) from 00-09 UTC on 12 April and a major storm period observed
at College (Fairbanks), AK. The remainder of the 12th saw quiet to
unsettled conditions. Late on the 12th, temperature and wind speed
began to rise signaling the end of the transient feature and the
beginning of the influence of a weak negative polarity cornal hole
high speed stream.Active conditions returned for the first two
synoptic periods of the13th followed by quiet to unsettled levels of
activity.



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