Product: Weekly Highlights and Forecasts
:Issued: 2025 Mar 31 0224 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and web contact www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 24 - 30 March 2025
Solar activity was low on 24-25 Mar, moderate on 26-27 Mar and 29 Mar, and high on 28 Mar and 30 Mar. High levels were reached on 28 Mar as the strongest event of the period, an X1.1 (R3-Strong) flare at 28/1521 UTC from yet-to-be-numbered Region 4046 (N05, L=301, class/area=Dho/270 on 30 Mar), was produced on the Sun's eastern limb. Associated with the event was a Type IV radio sweep and a Tenflare (380 sfu). The resulting fast-moving CME was analyzed and modelled. The results suggested the far flank of the CME would pass close, but ultimately miss Earth. High solar activity levels were again reached on 30 Mar due to frequent R1 flares from Region 4048 (S15, L=281, class/area=Eki/300 on 30 Mar). A total of six events were observed, the largest of which was an M1.6 (R1) flare at
30/1642 UTC.
Other activity included Type II radio sweeps on 25 Mar and 26 Mar. Both of these events were associated with non-Earth-directed CME events on or beyond the W. limb.
No proton events were observed at geosynchronous orbit. However, an increase above background was observed two days after the X1.1 flare at 28/1521 UTC. Although delayed, the rise in proton flux is likely related to this event.
The greater than 2 MeV electron flux at geosynchronous orbit climbed to high levels on 27-30 Mar. This increase in electron flux was caused by the influence of a strong, positive polarity CH HSS, which began around 26 Mar.
Geomagnetic field activity ranged from quiet to G2 (Moderate) geomagnetic storms. Active conditions on 24 Mar were associated with the passage of a CME that left the Sun on 21 Mar. On 25 Mar active conditions were again observed due to the onset of CIR ahead of a positive polarity CH HSS. Geomagnetic activity increased to G2 (Moderate) levels on 26 Mar as total magnetic field strength reached a brief peak of 29 nT and the Bz component reached as far south as -27 nT.
Wind speeds increased from above ~600 km/s on 26 Mar to above ~800 km/s on 27 Mar. The geomagnetic field responded with a mix of active to G1 (Minor) storm conditions. As total magnetic field strength and solar wind speeds declined on 28 Mar, geomagnetic conditions decreased to mostly unsettled to active levels. During the final waning stage of the positive polarity CH, an isolated period of active was last observed early on 29 Mar and only quiet conditions were observed over 30 Mar.
Forecast of Solar and Geomagnetic Activity 31 March - 26 April 2025
Solar activity will continue at a chance for R1-R2 (Minor-Moderate) throughout the outlook period due to multiple complex regions on the visible disk as well as on the Sun's farside that are likely to return. A slight chance exists for R3 (Strong) events over the next three days primarily due to the flare potential from complex regions in the Sun's eastern hemisphere.
No proton events are expected at geosynchronous orbit are likely to remain below the S1 (Minor) solar radiation storm threshold (proton flux of 10 pfu).
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at high levels on 31 Mar, 06-14 Apr, and 23-26 Apr in response to multiple, recurrent, CH HSSs. The remainder of the outlook period is expected to be at normal to moderate levels.
Geomagnetic field activity is expected to range from quiet to G2 (Moderate) geomagnetic storm conditions. G2 conditions are likely on 05 Apr and 09 Apr; G1 (Minor) conditions are likely over 04 Apr, 08 Apr, and 10 Apr, active conditions are likely over 11 Apr, 13 Apr, and 21-24 Apr; unsettled conditions are likely on 03 Apr, 06-07 Apr, 12 Apr, 14-15 Apr, 17-20 Apr, and 25-26 Apr. All increases in geomagnetic activity are anticipated in response to multiple, recurrent, CH HSSs. The remainder of the outlook period is likely to
mostly quiet.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2025 Mar 31 0225 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and web contact www.swpc.noaa.gov/content/subscription-services
#
# 27-day Space Weather Outlook Table
# Issued 2025-03-31
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2025 Mar 31 170 5 2
2025 Apr 01 175 5 2
2025 Apr 02 175 5 2
2025 Apr 03 175 10 3
2025 Apr 04 180 20 5
2025 Apr 05 180 35 6
2025 Apr 06 180 10 3
2025 Apr 07 185 12 3
2025 Apr 08 185 30 5
2025 Apr 09 180 35 6
2025 Apr 10 175 25 5
2025 Apr 11 175 18 4
2025 Apr 12 175 10 3
2025 Apr 13 175 15 4
2025 Apr 14 170 12 3
2025 Apr 15 170 8 3
2025 Apr 16 175 5 2
2025 Apr 17 175 10 3
2025 Apr 18 175 12 3
2025 Apr 19 170 8 3
2025 Apr 20 170 10 3
2025 Apr 21 165 15 4
2025 Apr 22 165 15 4
2025 Apr 23 170 15 4
2025 Apr 24 170 15 4
2025 Apr 25 165 10 3
2025 Apr 26 165 8 3
(NOAA)
