:Product: Weekly Highlights and Forecasts
:Issued: 2016 Jul 25 0218 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
18 - 24 July 2016

Solar activity was low on 18-20 and 22 July with multiple C-class
flares from Regions 2565 (N04,L=175, class/area Dho/320 on 16 July)
and 2567 (N05, L=166, class/area Dki/380 on 21 July). The largest
flare during that period was a C4.6 from Region 2567 at 20/2215 UTC.
Moderate solar levels were observed on 21 and 24 July with four
M-class flares observed from Region 2567. The largest flare during
that period was an M2.0 observed at 24/0620 UTC. Activity reached
high levels on 23 July with three M-class flares from Region
2567.span id="OLK_SRC_BODY_SECTION"span The first was an M5.0,
which peaked at 23/0211 UTC. The second was an M7.6/2b flare with an
associated 310 sfu Tenflare. The final was an M5.5/3b, which peaked
15 minutes later at 23/0531 UTC had accompanying Type II (729 km/s
shock velocity) and Type IV radio emissions, as well as a 900 sfu
Tenflare. Two CMEs were observed in coronagraph imagery lifting off
the west limb at 23/0524 UTC and 23/0548 UTC. Both CMEs were
determined to not have an Earth-directed component./span/span

No proton events were observed at geosynchronous orbit. However, a
slight enhancement to near 1 pfu was observed at 23/0725 UTC due to
the flare activity from early on 23 July.

The greater than 2 MeV electron flux at geosynchronous orbit was at
high levels on 18-19 July, normal levels from 20-23 July, and
moderate levels on 24 July.

Geomagnetic field activity reached minor storm levels on 19-20 and
24 July due to the shock arrival of two CMEs. The first shock
arrival was likely associated with flare activity on 16 July and was
observed at the ACE spacecraft at 19/2310 UTC with a speed of
approximately 450 km/s. The Bt component increased from near 5 nT to
17 nT and Bz reached a maximum southward deviation of -12 nT. Minor
storm levels were observed from 19/2355 until 20/0600 UTC. The
second shock enhancement was observed near 24/1450 UTC and likely
associated with flare activity on 20 July. Wind speeds increased
from near 400 km/s to 470 km/s accompanied by a Bt enhancement from
5 nT to 13 nT and southward deflection of Bz to -9 nT for nearly
three hours. Minor storm conditions were observed with this event
during the 24/1800-2100 UTC synoptic period. Geomagnetic field
activity was quiet on 18, 21-23 July with a nominal solar wind.

Forecast of Solar and Geomagnetic Activity
25 July - 20 August 2016

Solar activity is expected to be very low to low for the first half
of the period with a chance for M-class flares from 05-19 August due
to the return of old Region 2567.

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 for the majority of the
period with high levels from 05-15 August due to recurrent CH HSS
events.

Geomagnetic field activity is expected to reach active levels on
25-27 July due to lingering CME effects and the arrival of a
positive polarity CH HSS. Active to minor storm levels are expected
on 29 July, 03-05, 08, and 10 August due to recurrent CH HSS
activity. Mostly quiet to unsettled conditions are expected for the
remainder of the period.