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000
FXXX12 KWNP 261231
DAYDIS

:Product: Forecast Discussion
:Issued: 2017 Jul 26 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 remained at very low levels. Region 2668 (N03, L=311) was
numbered and quickly decayed into a plage region. No Earth-directed CMEs
were observed in available satellite imagery.

.Forecast...
Solar activity is expected to be very low on days one through three
(26-28 Jul).

Energetic Particles

.24 hr Summary...
The greater than 2 MeV electron flux was at high levels with a peak flux
of 18,800 pfu observed at 25/1515 UTC. The greater than 10 MeV proton
flux climbed above normal background levels, peaking around 2 pfu at
25/1930 UTC, possibly as a result of CME activity on the far side of the
Sun on 23 Jul. Nonetheless, 10 MeV protons remained well below the 10
pfu warning threshold.

.Forecast...
The greater than 2 MeV electron flux is expected to reach high levels
over the next three days (26-28 Jul). The greater than 10 MeV proton
flux is expected to remain below threshold and recover to normal
background levels throughout the forecast period.

Solar Wind

.24 hr Summary...
Solar wind parameters reflected the continued influence of a positive
polarity CH HSS. Solar wind speeds remained elevated, averaging around
600 km/s, for most of the period. Total field measurements ranged
between 1 and 8 nT while the Bz component was variable between +/- 5 nT.
The phi angle was in a predominately positive orientation, with a few
oscillations into the negative sector throughout the period.

.Forecast...
Solar wind parameters are expected to trend towards background levels on
day one (26 Jul) as CH HSS effects weaken. Days two and three (27-28Jul)
are expected to be at near nominal levels.

Geospace

.24 hr Summary...
The geomagnetic field was at quiet to active levels due to continued
effects from a positive polarity CH HSS.

.Forecast...
The geomagnetic field is expected to be at quiet to unsettled levels on
day one (26 Jul), with a chance for isolated active levels due to
continued CH HSS effects. Days two and three (27-28 Jul) are expected to
be quiet as solar wind parameters settle back to nominal in the wake of
the CH HSS.