:Product: Weekly Highlights and Forecasts
:Issued: 2016 Sep 26 0103 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/weekly.html
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
19 - 25 September 2016

Solar activity reached low levels this period due to isolated
C-class flare activity. Region 2595 (N11, L=099, class/area=Dao/120
on 20 Sep) was the most productive region this period. In addition
to multiple low-level C-class flares Region 2595 produced the
largest event of the period, a C5 flare at 22/0547 UTC. Region 2597
(S13, L=349, class/area=Dsc/120 on 24 Sep) developed late in the
week and produced an isolated C1 flare at 25/1914 UTC in addition to
numerous B-class flares. No Earth-directed coronal mass ejections
were observed this period.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels on 21 Sep, moderate levels on 22-23 Sep, and was at
normal levels throughout the remainder of the period.

Geomagnetic field activity reached G1 (Minor) geomagnetic storm
levels on 20 Sep with active levels observed on 21 Sep in response
to the influence of a negative polarity coronal hole high speed
stream. G1 (Minor) storm levels were observed again on 25 Sep due to
prolonged periods of southward interplanetary magnetic field
orientation. Quiet conditions were observed on 22-24 Sep and quiet
to unsettled levels were observed on 19 Sep under a background solar
wind environment.

Forecast of Solar and Geomagnetic Activity
26 September - 22 October 2016

Solar activity is expected to be at very low levels throughout the
period with a chance for C-class flare activity.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be very high on 02 Oct with high levels expected on 29
Sep-01 Oct, 03-11 Oct, and 18 Oct following periods of an enhanced
solar wind environment associated with coronal hole high speed
stream influence. Normal and normal to moderate flux levels are
expected throughout the remainder of the period.

Geomagnetic field activity is likely to reach G2 (Moderate)
geomagnetic storm levels on 28-30 Sep and G1 (Minor) storm levels on
26 Sep, 01-02 Oct, and 17 Oct due to the anticipated influence of
multiple, recurrent coronal hole high speed solar wind streams.
Active conditions are expected on 27 Sep, 03 Oct, and 18 Oct with
generally quiet and quiet to unsettled conditions likely throughout
the remainder of the period.