Report of Solar Geophysical Activity (RSGA)

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 105 Issued at 2200Z on 15 Apr 2013

IA.  Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
15/1403Z from Region 1723 (S18E20). There are currently 6 numbered
sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on day one (16 Apr) and expected to be low
with a slight chance for an M-class flare on day two (17 Apr) and likely
to be low on day three (18 Apr).

IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
541 km/s at 14/2245Z. Total IMF reached 12 nT at 14/2153Z. The maximum
southward component of Bz reached -4 nT at 15/2058Z.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one, two, and three (16 Apr, 17 Apr, 18
Apr).

III.  Event probabilities 16 Apr-18 Apr
Class M    25/15/05
Class X    05/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           15 Apr 113
Predicted   16 Apr-18 Apr 110/105/100
90 Day Mean        15 Apr 112

V.  Geomagnetic A Indices
Observed Afr/Ap 14 Apr  010/010
Estimated Afr/Ap 15 Apr  005/005
Predicted Afr/Ap 16 Apr-18 Apr  005/005-005/005-004/005

VI.  Geomagnetic Activity Probabilities 16 Apr-18 Apr
A.  Middle Latitudes
Active                10/10/10
Minor Storm           01/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/15/15
Major-severe storm    10/05/10
**** SPACE WEATHER OUTLOOK ****

Summary For April 8-14

A category R2 (Moderate) radio blackout was observed on 11 April due to flare activity from active sunspot Region 1719.
A category R1 (Minor) radio blackout was observed on 12 April due to flare activity from active sunspot Region 1718.
A category S1 to S2 (Minor to Moderate) solar radiation storm was observed on 11 - 12 April due to solar activity from active sunspot Region 1719.

Outlook For April 15-21

No space weather storms are expected.


NOAA Space Weather Scale descriptions can be found at

www.sec.noaa.gov/NOAAscales