Product: Weekly Highlights and Forecasts
:Issued: 2026 Mar 23 0245 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 16 - 22 March 2026
Solar activity reached moderate levels on 16-18 Mar, with low levels observed on 19-22 Mar. Region 4392 (S16, L=018, class/area=Csi/200 on 17 Mar) produced most of the flare activity observed throughout
the week, including three M-flares (R1-Minor). AR4392 produced an M2.7 flare at 16/1215 UTC with accompanying Type-II (est. 1,227 km/s), Type-IV, and Tenflare (380 sfu) emissions. The subsequent
asymmetric halo CME, first observed in LASCO C2 imagery at 16/1236 UTC, arrived at Earth on 20 Mar. AR4392 produced another M2.7 flare at 18/0842 UTC with accompanying Type-II (est. 860 km/s) and
Tenflare (229 sfu) emissions. The associated CME, first visible in LASCO C2 imagery at 18/0936 UTC, arrived simultaneously with the 16 Mar CME on 20 Mar.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 16-20 and 22 Mar. Normal to moderate levels were observed on 21 Mar following a period of an elevated geomagnetic field
activity.
Geomagnetic field activity reached G1-G3 (Minor-Strong) geomagnetic storm levels on 20-22 Mar, following the arrival of multiple CMEs (that left the Sun on 16 and 18 Mar) on 20 Mar. The remainder of the
period was at quiet and quiet to unsettled levels under ambient solar wind conditions.
Forecast of Solar and Geomagnetic Activity 23 March - 18 April 2026
Solar activity is expected to be at low levels with a varying chance for M-class (R1-R2/Minor-Moderate) flares through 18 Apr.
No proton events are expected at geosynchronous orbit, barring significant flare activity.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels on 23-25, 27-28, 30-31 Mar and 04-09, 11-15 Apr. Normal to moderate flux levels are expected to prevail
throughout the remainder of the period.
Geomagnetic field activity is expected to reach G1-G2 (Minor-Moderate) geomagnetic storm levels on 23 Mar due to negative polarity CH HSS influences. Periods of G1 (Minor) storming are
likely on 03-04 Apr in response to negative polarity CH HSS influences. Periods of G1 (Minor) storming are likely on 09 and 11 Apr, with G2 (Moderate) storm periods likely on 10 Apr, due to
positive polarity CH HSS influences. G2 (Moderate) storm periods are likely again on 18 Apr following the onset of negative polarity CH HSS influences.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2026 Mar 23 0245 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/content/subscription-services
#
# 27-day Space Weather Outlook Table
# Issued 2026-03-23
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2026 Mar 23 120 34 6
2026 Mar 24 120 14 3
2026 Mar 25 122 12 3
2026 Mar 26 125 12 3
2026 Mar 27 130 8 3
2026 Mar 28 130 5 2
2026 Mar 29 128 8 3
2026 Mar 30 125 15 4
2026 Mar 31 125 10 3
2026 Apr 01 130 5 2
2026 Apr 02 120 5 2
2026 Apr 03 120 18 5
2026 Apr 04 115 24 5
2026 Apr 05 110 10 3
2026 Apr 06 120 15 4
2026 Apr 07 120 8 3
2026 Apr 08 118 7 2
2026 Apr 09 120 25 5
2026 Apr 10 110 40 6
2026 Apr 11 112 20 5
2026 Apr 12 115 12 3
2026 Apr 13 115 8 3
2026 Apr 14 110 7 2
2026 Apr 15 115 5 2
2026 Apr 16 115 4 2
2026 Apr 17 120 7 2
2026 Apr 18 122 48 6
(NOAA)
