:Product: Weekly Highlights and Forecasts
:Issued: 2016 May 16 0334 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
09 - 15 May 2016

Solar activity was low and only C-class flare activity was observed.
Region 2543 (S05, L=002, class/area=Dao/90 on 10 May) produced a C7
flare at 14/1134 UTC which was the largest event of the period.
Region 2544 (N21,L=296, class/area=Dao/150 on 15 May) produced five
low-level C-class flares on 15 May, the largest being a C1 at
15/0502 UTC. Region 2542 (N12, L=357, class/area=Dai/150 on 09 May)
produced a long-duration C3 flare at 15/1603 UTC with an associated
filament eruption and partial-halo coronal mass ejection (CME) that
departed off of the west limb. Forecaster analysis and WSA/Enlil
modelling determined that the CME did not have an Earth-directed
component. There were no Earth-directed CMEs during the period.

No proton events were observed at geosynchronous orbit. However, a
slight enhancement was observed on 15 May associated with a
long-duration C3 flare and filament eruption near Region 2542. A
peak flux of 2 pfu was observed on 15 May at 2315 UTC.

The greater than 2 MeV electron flux at geosynchronous orbit was at
very high levels from 09-13 May due to the influences of a negative
polarity coronal hole high speed stream (CH HSS). High levels were
observed on 14 May and moderate levels rounded out the week on 15
May.

Geomagnetic field activity was at unsettled to G3 (Strong)
geomagnetic storm levels on 09 May due to the residual effects of a
co-rotating interaction region and subsequent negative polarity
coronal hole high speed stream (CH HSS). Mainly quiet to unsettled
conditions were observed for 10-14 May with a nominal solar wind. A
positive polarity CH HSS became connected with Earths magnetic field
on 15 May causing quiet to active conditions.

Forecast of Solar and Geomagnetic Activity
16 May - 11 June 2016

Solar activity is expected to be at very low (B-class flares) to low
(C-class flares) levels throughout the outlook period.

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 16-23 May, 30 May-02 Jun, and 06-10
Jun. Moderate flux levels are expected for the remainder of the
period.

Geomagnetic field activity is expected to reach G1 (Minor)
geomagnetic storm levels on 16, 19-20 May due to the influence of
recurrent positive polarity coronal hole high speed streams (CH
HSS). G1 (Minor) storm levels are also expected on 29 May and 04-05
June due to the influnce of negative polarity CH HSSs.