:Product: Weekly Highlights and Forecasts
:Issued: 2016 May 23 0405 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
16 - 22 May 2016

Solar activity was low with only B-class and C-class flare activity
observed. Regions 2544 (N20, L=295, class/area=Dai/160 on 16 May)
and 2546 (S07, L=223, class/area=Cho/550 on 21 May) produced three
low-level C-class flares between them, with the largest being a C1.8
at 16/1525 UTC from Region 2544. No Earth-directed coronal mass
ejections (CME) were observed during the reporting period.

No proton events were observed at geosynchronous orbit. However,
there was a slight enhancement on 16 May from a long duration C3
flare that occured previous to the reporting period. The greater
than 10 MeV proton flux reached a maximum of 1 pfu at 16/0030 UTC.

The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels on 16, 17, and 19 May and moderate levels on 18, 20-22
May.

Geomagnetic field activity was mostly at quiet to unsettled levels
from 16-20 May with an isolated period of active conditions on 17
May in response to a positive polarity coronal hole high speed
stream (CH HSS). G1 (Minor) geomagnetic storm levels were observed
during the 0600-0900 UTC synoptic period on 21 May due to influences
from another positive polarity CH HSS.

Forecast of Solar and Geomagnetic Activity
23 May - 18 June 2016

Solar activity is expected to be 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 reach high levels on 28-29 May, 01 Jun, 03-09 Jun, 12-13
Jun, and 18 Jun. Moderate flux levels are expected for the remainder
of the outlook period.

Geomagnetic field activity is expected to reach G2 (Moderate)
geomagnetic storm levels on 04 Jun and G1 (Minor) geomagnetic storm
levels on 05 Jun due to the influence of a negative polarity CH HSS.
Active geomagnetic levels are expected on 26 May, 30-31 May, 02-03
Jun, 06 Jun, 11-13 Jun, and 17-18 Jun due to various recurrent CH
HSSs.