972
FXXX12 KWNP 170031
DAYDIS

:Product: Forecast Discussion
:Issued: 2024 Jul 17 0030 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
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Solar Activity

.24 hr Summary...
Solar activity reached high levels today as Region 3738 (N09W83,
Fki/beta-gamma-delta) produced and X1.9/1B flare (R3-Strong) at 16/1326
UTC. Accompanying the flare were Type II (398 km/s) and Type IV radio
sweeps, a Castelli U radio signature, as well as a CME off the W limb
beginning at 16/1336 UTC in SOHO/LASCO C2 imagery. Preliminary analysis
of the CME showed no Earth-directed component. Another CME was analyzed
that began at 16/0848 UTC off the NW limb. This CME was likely
associated with an M3.6/1B flare (R1-Minor) at 16/0737 UTC from Region
3753 (N12W36, Dai/beta). Modelling indicated no Earth-directed
component.

Some decay was noted in the trailing spots as Region 3738 began its
transit around the W limb. Slight growth and separation appeared in
Region 3751 (S08E41, Ekc/beta-gamma). New Region 3757 (N17E74,
Hsx/alpha) was numbered. The rest of the spot groups were either stable
or slightly decaying.

Other activity included an M1.9 (R1) flare at 16/2206 UTC from Region
3744 (N16W16, Cao/beta). Associated with the event was Type II radio
sweep (est. 633 km/s). Further coronagraph imagery is needed to identify
any potential ejecta that may have been produced by the event.

.Forecast...
Solar activity is likely to be moderate (R1-R2, Minor-Moderate) with a
chance for further X-class flares (R3, Strong) on 17 Jul. X-class flare
probabilities are expected to decrease to a slight chance on 18-19 Jul
as Region 3738 rotates further around the W limb.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux was at normal to moderate levels
and the greater than 10 MeV proton flux was steady at background levels.

.Forecast...
The greater than 2 MeV electron flux is expected to be at normal to
moderate levels on 17-19 Jul. There is a chance for S1 (Minor) storm
levels on 17 Jul due to the location and flare potential of Region
3738. As region 3738 rotates further around the west limb on 18-19 Jul,
probabilities decrease to a slight chance.

Solar Wind

.24 hr Summary...
Solar wind parameters were enhanced under CME influence. Total field
increased to a maximum of 17 nT at 16/0526 UTC before decreasing to end
of period levels near 9 nT. The Bz component was mostly positive ranging
from +13 nT to -7 nT. Solar wind speed was at nominal levels ranging
from 324-423 km/s. Phi angle switched from a mostly negative orientation
to positive at 16/1330 UTC.

.Forecast...
Solar wind parameters are expected to continue to diminish through early
on 17 Jul. By mid to late on 18 Jul, conditions are likely to become
enhanced due to the onset of a negative polarity CH HSS.

Geospace

.24 hr Summary...
The geomagnetic field was quiet to unsettled.

.Forecast...
Quiet to unsettled levels are expected through 19 Jul with active
periods likely on 18 Jul due to the onset of a negative polarity CH HSS.