Product: Weekly Highlights and Forecasts
:Issued: 2026 Jun 01 0157 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 25 - 31 May 2026
Solar activity reached moderate levels on 29 May when Region 4455 (N15, L=83, class/area=Eko/370 on 29 May) produced an M1.1/Sf flare at 29/0704 UTC; the largest flare of the period. Solar activity was low with C-flare activity observed throughout the remainder of the week.
The greater than 10 MeV proton flux became enhanced late on 25 May following an eruption from beyond the NW limb. The greater than 10 MeV proton flux exceeded S1 (Minor) levels at 26/0010 UTC, and reached a peak flux of 2,380 pfu at 26/0110 UTC before decreasing below S1 levels by 26/0540 UTC. The greater than 100 MeV proton flux also became enhanced following this event, but did not exceed alert threshold.
The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels throughout the period.
Geomagnetic field activity reached unsettled levels on 25 and 27 May, with active levels observed on 26, and 28-31 May, as negative polarity CH HSS influences prevailed throughout the period.
Forecast of Solar and Geomagnetic Activity 01 June - 27 June 2026
Solar activity is expected to be at predominantly low levels throughout the outlook period, with a chance for M-class (R1-R2/Minor-Moderate) flare activity.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels on 12-20 Jun, with normal to moderate levels likely throughout the remainder of the period.
Geomagnetic field activity is likely to reach G2 (Moderate) storm levels on 11 Jun, with G1 (Minor) storming likely on 12 Jun, due to negative polarity CH HSS influences. Active conditions are likely on 01, 03-05, 13-14, and 23-27 Jun due to multiple recurrent CH HSSs. Quiet and quiet to unsettled conditions are expected to prevail throughout the remainder of the outlook period.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2026 Jun 01 0157 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 2026-06-01
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2026 Jun 01 135 10 4
2026 Jun 02 135 8 3
2026 Jun 03 130 14 4
2026 Jun 04 130 12 4
2026 Jun 05 125 10 4
2026 Jun 06 125 8 3
2026 Jun 07 125 5 2
2026 Jun 08 120 5 2
2026 Jun 09 120 5 2
2026 Jun 10 130 5 2
2026 Jun 11 135 30 6
2026 Jun 12 135 25 5
2026 Jun 13 130 12 4
2026 Jun 14 130 10 4
2026 Jun 15 140 8 3
2026 Jun 16 140 5 2
2026 Jun 17 150 5 2
2026 Jun 18 155 5 2
2026 Jun 19 160 5 2
2026 Jun 20 160 5 2
2026 Jun 21 165 8 3
2026 Jun 22 160 8 3
2026 Jun 23 155 10 4
2026 Jun 24 145 15 4
2026 Jun 25 145 15 4
2026 Jun 26 150 15 4
2026 Jun 27 150 15 4
(NOAA)
