445
FXXX12 KWNP 191156
DAYDIS

:Product: Forecast Discussion
:Issued: 2026 Aug 19 1155 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
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#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity continued at low levels, with most of the C-class
activity originated at Region 4507 (N04W62, Ehi/beta-gamma-delta). The
secondary source of C-class flares was beyond the East-limb and was
responsible for the largest flare of the period, a C5.0 at 19/0454 UTC.
There were four numbered regions on the visible disk, most of them
showed some decay (loosing intermediary/trailer spots or penumbra area).
Region 4510 (N12W88, Dao/beta) continued to rotate off the West-limb
during the day.

No Earth-directed CME was observed in the available coronagraph imagery
during the period.

.Forecast...
Solar activity is expected to continue at low levels over 19-21 Aug,
with a chance for M-class flares (R1-R2/Minor-Moderate).

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit remained at
normal to moderate levels. The greater than 10 MeV proton flux at
geosynchronous orbit remained at background levels.

.Forecast...
The greater than 2 MeV electron flux is likely to remain at low to
moderate levels through 20 Aug. High levels are likely by 21 Aug due to
CH HSS influences. The greater than 10 MeV proton flux is expected to
remain at background levels through 20 Aug.

Solar Wind

.24 hr Summary...
Solar wind parameters reflected the waning effect of the CIR and
dominating influence of a negative polarity coronal hole high speed
stream near Earth. Total magnetic field strength decrease from 15 nT
levels to values between 5-10 nT after 18/1900 UTC. Around the same
time, the Bz oscillation range diminished from +/- 10 nT to +/- 5 nT and
solar wind speeds increased from 400 km/s to about 550-600 km/s. Phi
angle remained predominantly negative during the past 24h.

.Forecast...
Solar wind parameters are likely to continue reflecting the presence of
high speed streams associated with negative polarity coronal hole(s)
through 21 Aug.

Geospace

.24 hr Summary...
The geomagnetic field ranged from quiet to G1 (Minor) storm levels. G1
levels were observed in two synoptic periods (18/1800-2100 UTC and
19/0300-0600 UTC) as a result of intervals with persistent Bz negative.

.Forecast...
The geomagnetic field is likely to reach G1 levels again until the end
of 19 Aug UTC-day due to negative polarity CH HSS influence. Mostly
active conditions are likely over 20-21 during the waning phase of the
CH HSS.