:Product: 0921RSGA.txt
:Issued: 2015 Sep 21 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 264 Issued at 2200Z on 21 Sep 2015

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to
21/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C8 event observed at
21/0518Z from Region 2420 (N10E64). There are currently 4 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 days one, two, and three (22 Sep, 23 Sep,
24 Sep).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: 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
660 km/s at 21/0649Z. Total IMF reached 8 nT at 21/0824Z. The maximum
southward component of Bz reached -6 nT at 20/2152Z. Protons greater
than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at
20/2105Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 374 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (22 Sep, 24
Sep) and quiet to active levels on day two (23 Sep). Protons greater
than 10 Mev have a slight chance of crossing threshold on day one (22
Sep).

III.  Event probabilities 22 Sep-24 Sep
Class M    40/30/25
Class X    05/05/05
Proton     10/05/05
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Sep 103
Predicted   22 Sep-24 Sep 105/105/110
90 Day Mean        21 Sep 103

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Sep  032/035
Estimated Afr/Ap 21 Sep  012/013
Predicted Afr/Ap 22 Sep-24 Sep  007/010-012/012-007/008

VI.  Geomagnetic Activity Probabilities 22 Sep-24 Sep
A.  Middle Latitudes
Active                25/25/10
Minor Storm           05/10/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                20/15/20
Minor Storm           30/25/25
Major-severe storm    30/35/20