Report of Solar Geophysical Activity (RSGA)

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 199 Issued at 2200Z on 18 Jul 2013

IA.  Analysis of Solar Active Regions and Activity from 17/2100Z to
18/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2 event observed at
18/1823Z from Region 1800 (S10E63). There are currently 7 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is likely to be low with a
slight chance for an M-class flare on days one, two, and three (19 Jul,
20 Jul, 21 Jul).

IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
560 km/s at 18/1732Z. Total IMF reached 18 nT at 18/1345Z. The maximum
southward component of Bz reached -11 nT at 18/1300Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 2285 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to minor storm levels on days one and two (19 Jul, 20
Jul) and unsettled to active levels on day three (21 Jul).

III.  Event probabilities 19 Jul-21 Jul
Class M    15/15/15
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           18 Jul 115
Predicted   19 Jul-21 Jul 120/125/125
90 Day Mean        18 Jul 121

V.  Geomagnetic A Indices
Observed Afr/Ap 17 Jul  005/004
Estimated Afr/Ap 18 Jul  010/015
Predicted Afr/Ap 19 Jul-21 Jul  013/020-013/020-011/015

VI.  Geomagnetic Activity Probabilities 19 Jul-21 Jul
A.  Middle Latitudes
Active                45/45/35
Minor Storm           20/20/15
Major-severe storm    05/05/01
B.  High Latitudes
Active                10/10/10
Minor Storm           25/25/30
Major-severe storm    65/65/50

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 2051
Begin Time: 2013 Jul 10 1655 UTC
Yesterday Maximum 2MeV Flux: 2286 pfu

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/NOAAscales

Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.