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868
FXXX12 KWNP 201230
DAYDIS

:Product: Forecast Discussion
:Issued: 2017 Aug 20 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 at moderate levels due to an M1 flare at 20/0152 UTC
from an emerging sunspot on the E limb. Multiple C-class flare activity
was also observed from this area of enhanced brightening. Region 2671
(N12E01, Fkc/beta-gamma) also produced a few C-class flares, of which
the largest was a C7/Sf flare, with an associated Type II (928 km/s)
radio sweep, observed at 19/2155 UTC. Coronal dimming was observed to
the north of the Region in SDO/AIA 193 imagery beginning at 19/2143 UTC
suggesting a CME was lifting off. We are currently awaiting updated
coronagraph imagery to determine if there is an Earth-directed
component.

.Forecast...
For the next three days (20-22 Aug), solar activity is likely to be at
low levels with a slight chance of M-class flares (R1-R2; Minor-Moderate
radio blackouts).

Energetic Particles

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to high levels with a
peak flux of 8,118 pfu observed at 19/1815 UTC. 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 high
levels all three days of the forecast period (20-22 Aug) while the
greater than 10 MeV proton flux is expected to remain at background
levels.

Solar Wind

.24 hr Summary...
Solar wind parameters were indicative of positive polarity CH HSS
influence. Solar wind speed began and ended the period near 700 km/s
with increased sample deviations above 800 km/s throughout the reporting
time-frame. Total field strength ranged between 2 and 6 nT while the Bz
component reached a low value of -6 nT with periods of sustained
negative values. The phi angle remained in a predominately positive
orientation.

.Forecast...
The solar wind environment is expected to remain enhanced through day
one (20 Aug). A gradual return to a more nominal wind regime is expected
through days two and three (21-22 Aug) as CH HSS influences slowly wane.

Geospace

.24 hr Summary...
The geomagnetic field was at unsettled to minor storm levels (G1-Minor)
due to positive polarity CH HSS influence.

.Forecast...
The geomagnetic field is expected to be at predominately unsettled to
active levels on day one (20 Aug) with minor storm levels (G1-Minor)
expected as CH HSS influence persists. Days two and three (21-22
Aug) are expected to be at quiet to isolated active levels as positive
polarity CH HSS influence persists.