Product: Weekly Highlights and Forecasts
:Issued: 2025 Sep 15 0137 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 08 - 14 September 2025
Solar activity was at low levels with only C-Class flares observed. The largest flare of the period was a C7.6 from Region 4207 (N28, L=48, class/area=Cso/80 on 11 Sep) at 11/1521 UTC. No significant CME activity was observed.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 09, 13, and 14 Sep due to influences from multiple coronal hole high speed streams (CH HSS). Normal to moderate levels were observed on 08, 10, 11, and 12 Sep.
Geomagnetic field activity reached G2 (Moderate) storm levels on 09 Sep due to sustained period of southward Bz. G1 (Minor) storm levels were observed on 14 Sep due to influences from a negative polarity CH HSS. Quiet to active levels were observed on the remaining days
of the highlight period.
Forecast of Solar and Geomagnetic Activity 15 September - 11 October 2025
Solar activity is expected to be at low levels with a chance for isolated M-class flares throughout the outlook period.
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 18-21 Sep and 06-11 Oct due to recurrent CH HSS influences. Normal to moderate levels are expected for the remainder of the outlook period.
Geomagnetic field activity is expected to be at G2 (Moderate) storm levels on 15 Sep due to influences from negative polarity CH HSS. Active to G1 (Minor) storm levels are expected on 16 Sep, 28-29 Sep, 03-07 Oct, and 11 Oct all due to recurrent CH HSS influences. Quiet to unsettled levels are expected for the remaining days in the outlook period.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2025 Sep 15 0137 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 2025-09-15
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2025 Sep 15 125 30 6
2025 Sep 16 120 12 4
2025 Sep 17 125 10 3
2025 Sep 18 130 5 2
2025 Sep 19 135 5 2
2025 Sep 20 135 5 2
2025 Sep 21 135 5 2
2025 Sep 22 135 5 2
2025 Sep 23 130 5 2
2025 Sep 24 125 5 2
2025 Sep 25 130 5 2
2025 Sep 26 125 5 2
2025 Sep 27 125 5 2
2025 Sep 28 130 12 4
2025 Sep 29 130 15 5
2025 Sep 30 125 8 3
2025 Oct 01 120 5 2
2025 Oct 02 115 5 2
2025 Oct 03 115 15 5
2025 Oct 04 110 12 4
2025 Oct 05 110 12 4
2025 Oct 06 115 15 5
2025 Oct 07 115 12 4
2025 Oct 08 110 8 3
2025 Oct 09 115 8 3
2025 Oct 10 115 5 2
2025 Oct 11 120 15 5
(NOAA)
