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000
FXXX12 KWNP 181231
DAYDIS

:Product: Forecast Discussion
:Issued: 2017 Aug 18 1230 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 very low. Region 2671 (N11E28, Fkc/beta-gamma) was
stable and only managed B-class activity. No Earth-directed CMEs were
observed in available coronagraph imagery.

.Forecast...
Solar activity is expected to remain very low with a slight chance of
M-class flares (R1-R2; Minor-Moderate radio blackouts) on days one and
two (18-19 Aug); and a decreasing chance of C-class flares all three
days (18-20 Aug). This expectation is based primarily on the decreased
activity trends of Region 2671.


Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to moderate levels
due to electron redistribution associated with CIR arrival and CH HSS
onset. The greater than 10 MeV proton flux continued at background
values.

.Forecast...
The greater than 2 MeV electron flux is expected to be at normal to
moderate levels on day one (18 Aug) and increase to moderate to high
levels on days two and three (19-20 Aug) due to continuing CH HSS
influences. The greater than 10 MeV proton flux is expected to remain at
background levels all three days.


Solar Wind

.24 hr Summary...
Solar wind parameters were indicative CH HSS inflences. Solar wind
speeds increased to maximum speeds averaging near 600 km/s. Total field
strength underwent a steady decreasing trend throughout the period from
values near 10 nT to 6 nT. The Bz component became less variable this
period and has settled to +/- 4 nT. The phi angle was positive.

.Forecast...
The solar wind environment is expected to remain enhanced for all three
days (18-20 Aug) due to CH HSS influences.


Geospace

.24 hr Summary...
The geomagnetic field was mostly quiet to active, with isolated periods
of G1 (Minor) storm levels early in the reporting period.

.Forecast...
The geomagnetic field is expected to be unsettled to active with
isolated periods of G1 (Minor) storming likely on day one (18 Aug) as CH
HSS influences continue. Unsettled to active levels are expected on days
two and three (19-20 Aug) as CH HSS effects diminish.