Product: Weekly Highlights and Forecasts
:Issued: 2025 Aug 18 0120 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC at www.swpc.noaa.gov/content/subscription-services
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 11 - 17 August 2025
Solar activity reached moderate levels on 11-12 Aug due to M-class (R1-Minor) flare activity observed. Region 4173 (S18, L=110, class/area=Dro/20 on 10 Aug) produced an M1.3 flare at 11/0352 UTC, while Region 4168 (N05, L=103, class/area=Eki/350 on 08 Aug) produced M1 flares at 11/1435, 11/1536, 12/0059, and 12/0123 UTC. Low levels of solar activity were observed over 13-17 Aug. No Earth-directed CMEs resulted from the activity observed over the past week.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 11-17 Aug.
Geomagnetic field activity reached active levels on 11-13 Aug, with quiet to unsettled levels observed on 14-15 Aug, due to positive polarity CH HSS influence. Quiet conditions prevailed over 16-17 Aug with the return of nominal solar wind conditions.
Forecast of Solar and Geomagnetic Activity 18 August - 13 September 2025
Solar activity is expected to be at low levels, with a varying chance for M-class flares (R1-R2/Minor-Moderate events), through 13 Sep.
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 21-22, 27-28 Aug, and 04-13 Sep.
Geomagnetic field activity is likely to reach G1 (Minor) storm levels on 19 Aug, and active levels on 20 Aug, due to negative polarity CH HSS influence. Active conditions are likely again on 28 Aug due to negative polarity CH HSS influence. Periods of G1-G2 (Minor-Moderate) storming are likely on 05 Sep, with active conditions likely on 04 and 06 Sep, due to positive polarity CH HSS influence. The remainder of the period is expected to be at quiet or quiet to unsettled levels.
:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2025 Aug 18 0120 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC at: www.swpc.noaa.gov/content/subscription-services
#
# 27-day Space Weather Outlook Table
# Issued 2025-08-18
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2025 Aug 18 115 12 3
2025 Aug 19 110 30 5
2025 Aug 20 110 18 4
2025 Aug 21 110 8 3
2025 Aug 22 110 8 3
2025 Aug 23 120 5 2
2025 Aug 24 125 5 2
2025 Aug 25 120 8 3
2025 Aug 26 120 8 3
2025 Aug 27 125 10 3
2025 Aug 28 125 12 4
2025 Aug 29 130 8 3
2025 Aug 30 130 10 3
2025 Aug 31 140 10 3
2025 Sep 01 150 8 3
2025 Sep 02 150 5 2
2025 Sep 03 140 5 2
2025 Sep 04 140 20 4
2025 Sep 05 135 35 6
2025 Sep 06 130 20 4
2025 Sep 07 130 15 3
2025 Sep 08 130 15 3
2025 Sep 09 120 15 3
2025 Sep 10 120 10 3
2025 Sep 11 115 5 2
2025 Sep 12 110 5 2
2025 Sep 13 110 5 2
(NOAA)
