Joint USAF/NOAA Report of Solar and Geophysical Activity 30 September 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Sep 30 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 Report of Solar and Geophysical Activity
SDF Number 273 Issued at 2200Z on 30 Sep 2011
IA. Analysis of Solar Active Regions and Activity from 29/2100Z
to 30/2100Z: Solar activity was moderate. Region 1305 (N12E01)
produced an M1/1f at 30/1906Z. A Type II Radio Sweep (estimated
speed 690 km/s) was associated with this event along with a 260 sfu
tenflare. Region 1305 has shown slight aerial and penumbral growth
and maintains a beta-gamma magnetic configuration. Region 1302
(N13W29) produced a C1/Sf at 30/0252Z and has a beta-gamma-delta
magnetic configuration. Region 1307 (N14E48) has grown slightly and
produced a C3 at 30/1847Z.
IB. Solar Activity Forecast: Solar activity is expected to be low
with M-class activity likely through the period (01-03 October),
mainly from Regions 1302 and 1305. There is a slight chance for
X-class activity from these regions as well.
IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z:
The geomagnetic field was quiet during the past 24 hours. The greater
than 2 MeV electron flux at geosynchronous orbit reached high levels
during the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled with a slight chance for isolated
active periods on days one and two (01-02 October). The increase in
activity is expected due to the anticipated arrival of a recurrent
coronal hole high speed stream (CH HSS) on day one and possible
effects on day two from a weak CME associated with the long duration
C2 event observed on 29 September. Mostly quiet conditions are
expected on day three (03 October).
III. Event Probabilities 01 Oct-03 Oct
Class M 60/60/60
Class X 20/20/20
Proton 15/15/15
PCAF green
IV. Penticton 10.7 cm Flux
Observed 30 Sep 138
Predicted 01 Oct-03 Oct 140/140/140
90 Day Mean 30 Sep 110
V. Geomagnetic A Indices
Observed Afr/Ap 29 Sep 016/015
Estimated Afr/Ap 30 Sep 005/005
Predicted Afr/Ap 01 Oct-03 Oct 008/010-008/008-005/005
VI. Geomagnetic Activity Probabilities 01 Oct-03 Oct
A. Middle Latitudes
Active 20/20/05
Minor storm 05/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 25/25/05
Minor storm 05/05/01
Major-severe storm 01/01/01