Product: Weekly Highlights and Forecasts
:Issued: 2017 Sep 25 0425 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/weekly.html
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 18 - 24 September 2017
Solar activity was at very low levels with a few B-class flares observed. Old active Region 2673 (S09, L=119), a major flare producer on its previous transit, returned on 24 Sep and was
numbered 2682 (S09, L=127, Hsx/180 on 24 Sep). No Earth-directed CMEs were detected during the period. No proton events were observed at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels throughout the period with a maximum flux of 36,942 pfu observed at 22/1655 UTC.
Geomagnetic field activity began the period on 18 Sep at mostly unsettled to G1 (Minor) storm conditions under the influence of a positive polarity CH HSS. During the 18th, solar wind speeds peaked at near 720 km/s, total field ranged between 2-6 nT while the Bz component varied between +5 nT to -6 nT. Quiet to unsettled conditions prevailed on 19-20 Sep under waning CH HSS influence. Mostly quiet conditions, with isolated unsettled intervals, were observed from 21-24 Sep. Beginning on 19 Sep, solar wind exhibited a steady decline in speed to a low of about 320 km/s at 24/2100 UTC. Thereafter, and through the remainder of 24 Sep, solar wind speed increased to near 415 km/s, total field peaked at 10 nT while the Bz component varied between +6 nT to -9 nT. A SSBC from a positive to a negative orientation was observed at about 24/1905 UTC.
Forecast of Solar and Geomagnetic Activity 25 September - 21 October 2017
Solar activity is expected to be at low levels, with a slight chance for M-class activity (R1-R2, Minor-Moderate), from 25 Sep - 07 Oct and from 20-21 Oct. This is primarily due to the flare potential
from Region 2682. Mostly very low levels are expected from 08-19 Oct. 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 26-27 Sep, 28 Sep - 09 Oct and 12-21 Oct due to CH HSS influence. Normal to moderate levels are
expected for the remainder of the outlook period.
Geomagnetic field activity is expected to be at unsettled to active levels on 26 Sep and 30 Sep, with G1 (Minor) storm conditions are expected on 27 Sep, 29 Sep and 11-14 Oct while G2 (Major) storm
conditions are expected on 28 Sep, all due to recurrent CH HSS activity. Mostly quiet conditions are expected for the remainder of the outlook period.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2017 Sep 25 0425 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/wwire.html
#
# 27-day Space Weather Outlook Table
# Issued 2017-09-25
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2017 Sep 25 90 16 4
2017 Sep 26 95 8 3
2017 Sep 27 95 25 5
2017 Sep 28 95 32 6
2017 Sep 29 95 25 5
2017 Sep 30 95 12 4
2017 Oct 01 95 8 3
2017 Oct 02 95 8 3
2017 Oct 03 95 8 3
2017 Oct 04 95 5 2
2017 Oct 05 95 5 2
2017 Oct 06 95 5 2
2017 Oct 07 90 5 2
2017 Oct 08 85 5 2
2017 Oct 09 76 5 2
2017 Oct 10 75 5 2
2017 Oct 11 74 25 5
2017 Oct 12 73 25 5
2017 Oct 13 72 25 5
2017 Oct 14 72 20 5
2017 Oct 15 72 8 3
2017 Oct 16 71 8 3
2017 Oct 17 74 5 2
2017 Oct 18 73 5 2
2017 Oct 19 78 5 2
2017 Oct 20 80 5 2
2017 Oct 21 85 5 2
(NOAA)
