Subject: Weekly Highlights of Solar and Geomagnetic Activity, 10 - 16 March 2025

:Product: Weekly Highlights and Forecasts
:Issued: 2025 Mar 17 0140 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# https://www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
10 - 16 March 2025

Solar activity was at moderate levels on 11 and 14 March with two
M1.1 flares observed. The first M1.1 flare was observed at 11/1304
UTC from Region 4024 (N05, L=289, class/area Cro/020 on 11 Mar). The
second M1.1 flare was observed at 14/2221 UTC from Region 4030 (S16,
L=123, class/area Eso/090 on 15 Mar). No significant radio or CMEs
were associated with these events. The remainder of the highlight
period was at low levels.

At about 16/0900 UTC, dimming and a possible DSF was observed near
Region 4023 (N25, L=177, class/area Hsx/030 on 11 Mar). A likely
faint, slow CME was observed in LASCO C2 imagery with a weak
Earth-directed component expected to arrive midday on 20 Mar.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
high levels on 10-16 March with a peak flux of 5,060 pfu observed at
16/1445 UTC.

Geomagnetic field activity was at quiet to unsettled levels on 10-11
March. Activity levels increased to active to minor storm (G1-Minor)
levels on 12-13 March and an isolated moderate storm (G2-Moderate)
level early on 14 March. Unsettled to active levels were observed
for the remainder of 14 March through 15 March with mostly quiet to
unsettled levels on 16 March. The enhanced activity levels on 12-16
March were due to a negative polarity CH HSS. During the active
period, solar wind speeds peaked at 500-550 km/s, Bt reached 12 nT
and Bz reached -10 nT levels.

Forecast of Solar and Geomagnetic Activity
17 March - 12 April 2025

Solar activity is expected to be at a chance for R1-R2
(Minor-Moderate) levels through the outlook period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at high levels on 17, 29-31 March and 06-12 April due
to recurrent CH HSS influences. Normal to moderate levels are
expected for the rest of the outlook period.

Geomagnetic field activity is expected to be at unsettled to active
levels on 17-21 March due to a combination of negative polarity CH
HSS effects and weak CME effects. Active to minor storm (G1-Minor)
levels are expected on 25-28 March due to recurrent positive
polarity CH HSS effects. Active to minor to major storm
(G1-G2/Minor-Moderate) levels are expected on 04-12 April due to
recurrent negative polarity CH HSS effects. Quiet to unsettled
levels are expected for the remainder of the period (subject to
change with any CME activity).


--- MBSE BBS v1.0.8.4 (Linux-x86_64)
* Origin: NOAA Space Weather Prediction Center (3:633/280.2@fidonet)