Routine Space Environment Product (Daily)
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FXXX12 KWNP 201231

:Product: Forecast Discussion
:Issued: 2014 Sep 20 1230 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
#             Forecast Discussion
Solar Activity

.24 hr Summary...
Solar activity was at low levels. New Region 2171 (S09E60, Dao/beta)
produced the largest event of the period, a C3 flare at 19/1832 UTC.
Region 2164 (S12W88, plage) was the only other region to produce any
flare activity; two C1 flares early in the period, before decaying to an
enhanced plage area. All other regions were either stable or in decay,
and all were unremarkable. An enhanced plage area was observed rotating
into view around the southeast limb, but it is still too early to
accurately determine its magnetic structure, and will wait to numbered
it until it rotates further onto the visible disk. No Earth-directed
coronal mass ejections (CMEs) were observed during the period.

Solar activity is likely to be low with slight chance for an M-class
flare (R1-Minor)for the next three days (20-22 Sep).

Energetic Particle

.24 hr Summary...
The greater than 10 MeV proton flux at geosynchronous orbit was at
background levels and the greater than 2 MeV electron flux at
geosynchronous orbit was at normal levels.

The greater than 10 MeV proton flux at geosynchronous orbit is expected
to be at or near background levels (Below S1-Minor) for the next three
days (20-22 Sep). The greater than 2 MeV electron flux at geosynchronous
orbit is expected to be at normal to moderate levels over the next three
days (20-22 Sep).

Solar Wind

.24 hr Summary...
The solar wind environment remained enhanced during the first half of
the period, following the previously discussed transient and/or coronal
hole activity. Solar winds, measured by the ACE spacecraft, observed
elevated wind speeds at the beginning of the period that ranged from an
initial speed near 440 km/s to a peak of 573 km/s at 19/2108 UTC. Just
prior to the new UT day, speeds settled into fairly consistent
velocities around 460 km/s, where they remained for the rest of the
period. Density and temperature signatures both indicated initial
elevated values, followed by a steady decreasing trend. IMF Bt began the
period with frequent fluctuations between 3 nT and 16 nT, but quickly
stabilized near 9 nT shortly after 19/1600 UTC. The Bz component of the
IMF also varied widely at the beginning of the period, reaching a max of
+13 nT while seeing a maximum southward deflection of -13 nT. It too,
exhibited some stability after 19/1600 UTC, varying between +/-7 nT. Phi
measurements initially had isolated oscillations from negative to
positive sectors until it stabilized and remained in a negative (toward)
orientation after 19/1600 UTC.

Solar wind parameters are expected to remain enhanced for the remainder
of day one into day two (21-22 Sep) as the elevated activity begins to
subside. A return to nominal levels is expected by day three (22 Sep).


.24 hr Summary...
The geomagnetic field was at quiet to unsettled levels with an isolated
active period from 19/1500-19/1800 UTC, attributed to the activity
associated with the aforementioned transient/CH HSS combination.

The geomagnetic field is expected to be at quiet to unsettled levels on
day one (20 Sep) as the CME/CH HSS influence wanes. Mostly quiet
conditions are expected on days two and three (21-22 Sep). is the U.S. government's official web portal to all federal, state and local government web resources and services.