Routine Space Environment Product (Daily)
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050
FXXX12 KWNP 211231
DAYDIS

:Product: Forecast Discussion
:Issued: 2026 Jul 21 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 reached moderate levels as Region 4493 (N05E01,
Dkc/beta-gamma-delta) produced an M2.5 at 20/1436 UTC, an M1.1 at
20/1920 UTC, and an M3.4 flare at 20/2225 UTC along with numerous
C-class flares. Region 4492 (N15E52, Dko/beta-gamma) was only
responsible for low level C-class flaring. Region 4493 underwent rapid
flux emergence and developed several delta magnetic configurations.
Slight growth was observed in Region 4492, but was relatively stable. No
Earth-directed CMEs were observed.

.Forecast...
Solar activity is expected to be low with further M-class flares (R1-R2,
Minor-Moderate) likely on 21-23 Jul primarily due to the flare potential
of AR 4493.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux reached high levels this period
with a peak flux of 1,300 pfu at 20/1730 UTC. The greater than 10 MeV
proton flux was steady at background levels.

.Forecast...
The greater than 2 MeV electron flux is expected to return to normal to
moderate levels on 21 July with a chance to reach high levels once again
by late on 22 July and continuing into 23 July. The greater than 10 MeV
proton flux is expected to continue at background levels through 23 Jul
with a 5% chance for an S1 or greater event primarily due to the flare
potential of AR 4493.

Solar Wind

.24 hr Summary...
Solar wind parameters became enhanced after 20/2245 UTC, likely
indicative of a CIR preceding a negative polarity CH HSS. Solar wind
speed increased from approximately 275 km/s to near 425 km/s. Total
field increased to 14 nT by 21/0718 UTC with the Bz component ranging
from +/-12 nT. Phi angle shifted from positive into a negative sector at
21/0407 UTC.

.Forecast...
CIR effects are expected to continue through mid to late on 21 Jul and
transition into a negative polarity CH HSS. Solar wind speeds reaching
700 km/s are likely based on recurrence. HSS conditions are expected to
continue through 23 Jul before gradually diminishing.

Geospace

.24 hr Summary...
The geomagnetic field was quiet to active due to CIR onset.

.Forecast...
Unsettled to active conditions are expected through the latter half of
the UTC day on 21 Jul with a chance for G1 (Minor) storming. G1 Storming
is likely through early to midday on 22 Jul as HSS conditions increase.
Unsettled to active conditions are expected on 23 July as HSS effects
persist.