Product: Weekly Highlights and Forecasts
:Issued: 2017 Apr 24 0153 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 17 - 23 April 2017
Solar activity reached low levels on 17-18 Apr due to isolated C-class flare activity from Region 2651 (N12, L=070, class/area=Cso/150 on 23 Apr), but solar activity was at very low levels through the remainder of the period (19-23 Apr). The largest event of the period, a long-duration C5/Sf flare at 18/2010 UTC with both Type-II and IV radio emissions, had an associated CME that was
observed in C2 coronagraph imagery beginning at 18/1948 UTC. CME analysis and WSA-Enlil modelling suggested that this event did not have an Earth-directed component, however, it is likely that this event reached Earth late on 21 Apr. No other Earth-directed CMEs were observed.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 17-18, 21-23 Apr, moderate levels on 20 Apr, and normal levels on 19 Apr.
Geomagnetic field activity was quiet on 17 Apr and quiet to unsettled on 18 Apr under a nominal solar wind regime. The influence of a recurrent, positive polarity CH HSS caused periods of G1 (Minor) geomagnetic storm conditions on 19 Apr and G1-G2 (Minor-Moderate) storm conditions on 20 Apr. The likely arrival of a CME (from 18 Apr) combined with the onset of a CIR caused G1 (Minor) geomagnetic storm levels late on 21 Apr. The influence of a recurrent, negative polarity CH HSS began early on 22 Apr and caused G1-G2 (Minor-Moderate) geomagnetic storms on 22-23 Apr.
Forecast of Solar and Geomagnetic Activity 24 April - 20 May 2017
Solar activity is expected to be very low with a chance for C-class flare activity throughout the outlook period (24 Apr-20 May).
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is likely to reach very high levels on 29-30 Apr with high levels likely on 24-28 Apr and 06-12, 17-20 May. Normal to moderate flux levels are expected for the remainder of the period.
Geomagnetic field activity is likely to reach G2 (Moderate) geomagnetic storm levels on 19-20 May with G1 (Minor) geomagnetic storms likely on 24-27 Apr and 01, 17-18 May due to the influence of multiple, recurrent CH HSSs. Active conditions are likely on 28 Apr and 05-06, 16 May with quiet or quiet to unsettled field activity expected for the remainder of the period.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2017 Apr 24 0153 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 2017-04-24
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2017 Apr 24 84 30 5
2017 Apr 25 84 20 5
2017 Apr 26 84 20 5
2017 Apr 27 84 20 5
2017 Apr 28 84 15 4
2017 Apr 29 84 8 3
2017 Apr 30 84 5 2
2017 May 01 80 20 5
2017 May 02 75 10 3
2017 May 03 75 10 3
2017 May 04 75 10 3
2017 May 05 75 15 4
2017 May 06 75 15 4
2017 May 07 75 8 3
2017 May 08 75 8 3
2017 May 09 75 5 2
2017 May 10 75 5 2
2017 May 11 75 5 2
2017 May 12 75 5 2
2017 May 13 75 5 2
2017 May 14 75 5 2
2017 May 15 80 8 3
2017 May 16 80 15 4
2017 May 17 80 30 5
2017 May 18 80 25 5
2017 May 19 85 45 6
2017 May 20 85 50 6
(NOAA)
