:Product: Forecast Discussion
:Issued: 2025 Mar 20 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
Solar Activity

.24 hr Summary...
Solar activity reached moderate levels due to an isolated M1.5/1n flare
at 19/2040 UTC from Region 4031 (N17W41, Dai/beta). Regions 4028
(S16W18, Dai/beta), 4034 (S13E11, Bxo/beta) and 4035 (N15E38, Dso/beta)
exhibited slight growth. Region 4026 (S19W49, Bxo/beta) re-emerged in
the SW quadrant. Regions in the NW quadrant, including 4020 (N19W74,
Axx/alpha), 4022 (N05W72, Hax/alpha), 4025 (N10W58, Cso/beta) and 4031
all appeared to be in a decay phase.

No Earth-directed CMEs were detected in available coronagraph imagery.

.Forecast...
C-class flares are expected to continue on 20-22 Mar, with a chance for
isolated M-class (R1-Minor) flares.

Energetic Particle

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

.Forecast...
The greater than 2 MeV electron flux is expected to be at normal to
moderate levels, with a chance for high levels, on 20-22 Mar. The
greater than 10 MeV proton flux is expected to continue at background
levels.

Solar Wind

.24 hr Summary...
Solar wind parameters were enhanced, possibly a combination of weak
transient and HSS activity. Total field ranged from a high of 13 nT
early in the period followed by a decrease after 19/2100 UTC to 4-6 nT.
The Bz component ranged from +6/-7 nT. Solar wind speeds were mostly in
the 440-515 km/s range. Phi angle was mostly negative.

.Forecast...
Weak disturbances in the solar wind are anticipated through 20 Mar in
response to persistent transient/HSS effects as well as possible
flanking influences of a nearby CME passage that departed the Sun on 17
Mar. Solar wind parameters are expected to slowly diminish on 21 Mar.
Another enhancement is expected late on 22 Mar due to the arrival of a
CIR preceding a negative polarity CH HSS.

Geospace

.24 hr Summary...
The geomagnetic field was at quiet to G1 (Minor) storming.

.Forecast...
Quiet to unsettled levels are expected for the remainder of 20 Mar as
CME/HSS conditions wane. Quiet to unsettled levels are expected on 21
Mar. By late on 22 Mar, unsettled to active levels are likely due to the
aforementioned CIR arrival.