:Product: Weekly Highlights and Forecasts
:Issued: 2016 Aug 22 0524 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
15 - 21 August 2016

Solar activity was at low levels on 15 August due to an isolated C1
flare at 15/0023 UTC from Region 2578 (N09, L=084, class/area
Cro/020 on 18 Aug). Very low levels were observed from 16-21 August.
Although Regions 2574 (N05, L=173, class/area Dho/290 on 09 Aug),
2576 (S15, L=160, class/area Hsx/140 on 10 Aug), 2577 (N03, L=164,
class/area Dso/130 on 12 Aug), and 2578 were on the visible disk
during the period, the regions appeared to be in slow decay. No
Earth-directed coronal mass ejections were observed.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
high levels on 15-16 August, moderate levels on 17 and 19-21 August
and normal levels on 18 August. The largest flux of the period was
9,570 pfu observed at 15/1605 UTC.

Geomagnetic field activity was at mostly quiet to unsettled levels
with an isolated active period observed on 21 August due to a pair
of weak, negative polarity coronal hole high speed streams (CH HSS).
Quiet levels were observed on 15 August under a nominal solar wind
regime. By early on 17 August, solar wind speed increased to 435
km/s while total field increased to near 9 nT. Quiet to unsettled
levels were observed from 16-18 August with quiet levels on 19-20
August. Solar wind speed decreased slowly until midday on 21 August
when another CH HSS became geoeffective. The geomagnetic field
responded with quiet to active levels on 21 August.

Forecast of Solar and Geomagnetic Activity
22 August - 17 September 2016

Solar activity is expected to be at very low to low levels through
the forecast period (22 Aug-17 Sep).

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal to moderate levels with high levels likely
on 26-28 August and from 31 August-12 September as a result of
recurrent CH HSS activity.

Geomagnetic field activity is expected to be at unsettled to active
levels from 23-25 August, 29 August-08 September, 13-14 September,
and again on 17 September with G1 (Minor) storm levels likely on
30-31 August due to recurrent CH HSS activity.