Product: Weekly Highlights and Forecasts
:Issued: 2026 Oct 05 0139 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 28 September - 04 October 2026
.JPG)
Solar activity was at very low to low levels throughout the summary
period. Region 4535 (N11, L=351, class/area Dao/060 on 30 Sep)
produced the strongest flare of the period; an impulsive C8.6/1f
event at 30/0246 UTC. This event also produced a 523 km/s Type II
and a Type IV Sweep. All other regions remained simple and absent of
any significant activity. No Earth-directed CMEs were observed in
available coronagraph imagery.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels on 28-30 Sep and 01 Oct with a peak of 5,620 pfu
observed at 29/1620 UTC. Moderate levels were observed on 02-04 Oct.
Geomagnetic field activity was at quiet levels on 28-30 Sep and
01-03 Oct with some isolated unsettled periods observed early on 03
Oct. On 04 Oct, solar wind parameters became enhanced due to the
influence of a positive-polarity CH HSS. Total magnetic field
strength increased to a peak of 22 nT and Bz observed several
southward deflections, the maximum being -20 nT early on 04 Oct.
Solar wind speeds steadily increased from about 300 km/s to a peak
of 644 km/s later on 04 Oct. The phi angle was predominantly
positive.
Forecast of Solar and Geomagnetic Activity 05 October - 31 October 2026
Solar activity is likely to continue at very low to low levels
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 be at high levels on 06-11 Oct, 14-17 Oct, and 23-28 Oct
due to anticipated incluence from multiple, recurrent CH HSSs.
Geomagnetic field activity is expected to reach G1 (Minor)
geomagnetic storm levels on 22 and 31 Oct. Active levels are likely
on 06, 21, and 23 Oct. Unsettled levels are likely on 07, 11-14, and
24 Oct. All increases in geomagnetic activity are associated with
anticipated influence from multiple, recurrent, coronal hole HSSs.
The remainder of the outlook period is likely to be at mostly quiet
levels.
:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2026 Oct 05 0139 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 2026-10-05
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2026 Oct 05 92 18 5
2026 Oct 06 90 12 4
2026 Oct 07 90 10 3
2026 Oct 08 90 8 3
2026 Oct 09 92 5 2
2026 Oct 10 92 5 2
2026 Oct 11 90 10 3
2026 Oct 12 90 8 3
2026 Oct 13 95 8 3
2026 Oct 14 100 8 3
2026 Oct 15 105 5 2
2026 Oct 16 105 5 2
2026 Oct 17 105 5 2
2026 Oct 18 105 5 2
2026 Oct 19 110 5 2
2026 Oct 20 105 5 2
2026 Oct 21 105 18 5
2026 Oct 22 100 22 5
2026 Oct 23 95 15 4
2026 Oct 24 90 10 3
2026 Oct 25 90 5 2
2026 Oct 26 85 5 2
2026 Oct 27 80 5 2
2026 Oct 28 75 5 2
2026 Oct 29 75 5 2
2026 Oct 30 75 5 2
2026 Oct 31 80 30 5
(NOAA)