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000
FXXX12 KWNP 240032
DAYDIS

:Product: Forecast Discussion
:Issued: 2017 Sep 24 0030 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
#
#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity was at very low levels.  A B3 flare was observed at
23/0603 UTC from the east limb near S07, likely the return of old Region
2673 (S09, L=119), however no spots were visible at the time of this
report.  Slight growth was observed in Region 2681 (S13E32, Cso/beta).
No Earth-directed CMEs were observed in available satellite imagery.

.Forecast...
Solar activity is likely to be at low levels with a slight chance for
M-class (R1-R2, Minor-Moderate) flares on days one through three (24-26
Sep).

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to high levels with a
maximum flux of 2,143 pfu at 23/1930 UTC.  The greater than 10 MeV
proton flux continued at background values.

.Forecast...
The greater than 2 MeV electron flux is likely to decrease to moderate
levels on day one (24 Sep) with the arrival of a CIR in advance of a
negative polarity CH HSS.  An increase to high levels is expected by
days two and three (25-26 Sep).  The greater than 10 MeV proton flux is
expected to remain at background levels.

Solar Wind

.24 hr Summary...
Solar wind parameters were at nominal levels.  Solar wind speed ranged
from approximately 360 km/s to 410 km/s.  Total field was between 1-5 nT
while the Bz component was variable between +/-4 nT.  Phi angle was
oriented in a mostly positive (away) sector with deviations into a
negative (towards) sector between 23/0700-1400 UTC.

.Forecast...
Solar wind parameters are expected to become enhanced on days one and
two (24-25 Sep) with the arrival of a negative polarity CH HSS.  A slow
decrease to nominal levels is expected on day three (26 Sep).

Geospace

.24 hr Summary...
The geomagnetic field was quiet.

.Forecast...
The geomagnetic field is expected to be at quiet to active levels on
days one and two (24-25 Sep) with quiet to unsettled levels on day three
(26 Sep) due to CH HSS effects.