Product: Weekly Highlights and Forecasts
:Issued: 2021 Oct 04 0141 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 27 September - 03 October 2021
Solar activity was at very low to low levels. Low levels were reached on 28 Sep - 01 Oct and 02-03 Oct. Region 2877 (S18, L=327, Class/Area Dao/200 on 30 Sep) produced the strongest flare of the period, a C2/Sn at 29/2156 UTC. Other activity included a C1 flare at 28/0634 UTC. Associated with the flare was a Type II radio sweep (534 km/s) and an partial-halo CME signature first seen in SOHO/LASCO imagery around 28/0634 UTC. Analysis and modeling of the event suggested onset at Earth late on 30 Sep - 01 Oct. The region produced two more low-level, impulsive, C-class flares before rotating around the SW limb on 03 Oct. Associated with the final C-flare was a Tenflare of 100 sfu at 03/0523 UTC. The remaining numbered active regions on the visible disk were relatively quiet
and stable.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels.
Geomagnetic field activity ranged from quiet to active conditions. Active conditions were observed 30 Sep and 01-02 Oct in response to the arrival of a CME that left the Sun on 28 Sep. Total field peaked at 14 nT around 30/1820 UTC. The onset of the magnetic cloud was observed after 01/1305 UTC and the Bz component was predominantly positive over the next 18 hours. Solar wind speeds began increasing from ~380 km/s midway through 30 Sep and peaked at ~560 km/s at 01/0120 UTC before gradually decreasing towards nominal levels over the next two days. Unsettled conditions were observed on 27-28 Sep due to influence from a positive polarity CH HSS. The remainder of the summary period was at quiet levels.
Forecast of Solar and Geomagnetic Activity 04 October - 30 October 2021
Solar activity is expected to be at very low levels with a chance for C-class flares over 04-10 Oct.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach moderate to high levels. High levels are likely on 20-21 Oct in response to recurrent coronal hole influence. The remainder of the outlook period is likely to be at normal to moderate levels.
Geomagnetic field activity is expected to range from quiet to active levels. Active levels are likely 19 Oct and unsettled levels are likely on 05-06 Oct, 08-09 Oct, 18 Oct, 20-21 Oct, and 25 Oct. All increases in geomagnetic activity are in response to anticipated influence from multiple, recurrent, CH HSSs. The remainder of the outlook period is expected to be quiet.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2021 Oct 04 0141 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 2021-10-04
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2021 Oct 04 88 5 2
2021 Oct 05 88 8 3
2021 Oct 06 88 8 3
2021 Oct 07 88 5 2
2021 Oct 08 88 8 3
2021 Oct 09 88 8 3
2021 Oct 10 85 5 2
2021 Oct 11 80 5 2
2021 Oct 12 75 5 2
2021 Oct 13 75 5 2
2021 Oct 14 75 5 2
2021 Oct 15 75 5 2
2021 Oct 16 75 5 2
2021 Oct 17 80 5 2
2021 Oct 18 85 10 3
2021 Oct 19 88 12 4
2021 Oct 20 90 10 3
2021 Oct 21 88 8 3
2021 Oct 22 88 5 2
2021 Oct 23 85 5 2
2021 Oct 24 85 5 2
2021 Oct 25 90 10 3
2021 Oct 26 100 5 2
2021 Oct 27 95 5 2
2021 Oct 28 90 5 2
2021 Oct 29 88 5 2
2021 Oct 30 88 5 2
(NOAA)
