Product: Weekly Highlights and Forecasts
:Issued: 2018 Apr 23 0149 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 16 - 22 April 2018
Solar activity was very low. Region 2706 (N03, L=281, class/area Dao/130 on 22 Apr) produced the strongest flare of the period, a B5 at 20/1704 UTC. The region continued slow growth through the end of the reporting period. 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 ranged from normal to high levels on 10-20 Apr; high levels on 22 Apr and
moderate to high levels for the remaining days of the reporting period. The peak flux observed was 24,100 pfu at 21/2120 UTC.
Geomagnetic field activity was quiet until 20 Apr, when unsettled to G2 (Moderate) geomagnetic conditions were observed in response to CIR ahead of a negative polarity CH HSS. Total field peaked at 23 nT around 20/0510 UTC and slowly declined to around 5 nT by late on 20 Apr. Solar wind speeds were increased from around 290 km/s to a peak of near 620 km/s during the HSS proper late on 20 Apr. The geomagnetic response decreased to quiet to unsettled conditions over 21 Apr and finally to quiet on 22 Apr as influence from the CH HSS waned.
Forecast of Solar and Geomagnetic Activity 23 April - 19 May 2018
Solar activity is expected to be very low throughout the forecast
period.
No proton events are expected at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at moderate to high levels on 23-30 Apr and 07-19
May; normal to moderate levels are expected from 01-06 May. Elevated levels of electron flux are expected due to the anticipation of multiple, recurrent CH HSSs.
Geomagnetic field activity is expected to reach unsettled levels on 26 Apr, 06 May, 09-10 May and 19 May; active levels are expected on 27 Apr, 07-08 Apr and 18 May; G2 (Moderate) geomagnetic storm conditions are likely on 17 May. All enhancements in geomagnetic field activity are associated with the anticipated influence of multiple, recurrent CH HSSs. The remaining days of the outlook
periods are expected to be mostly quiet.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2018 Apr 23 0149 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 2018-04-23
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2018 Apr 23 75 5 2
2018 Apr 24 75 5 2
2018 Apr 25 75 5 2
2018 Apr 26 75 8 3
2018 Apr 27 75 12 4
2018 Apr 28 75 5 2
2018 Apr 29 75 5 2
2018 Apr 30 75 5 2
2018 May 01 75 5 2
2018 May 02 75 5 2
2018 May 03 70 5 2
2018 May 04 70 5 2
2018 May 05 70 5 2
2018 May 06 70 10 3
2018 May 07 70 15 4
2018 May 08 70 12 4
2018 May 09 70 10 3
2018 May 10 70 8 3
2018 May 11 70 5 2
2018 May 12 70 5 2
2018 May 13 70 5 2
2018 May 14 70 5 2
2018 May 15 70 5 2
2018 May 16 70 5 2
2018 May 17 75 42 6
2018 May 18 75 12 4
2018 May 19 75 8 3
(NOAA)