Joint USAF/NOAA Report of Solar and Geophysical Activity 16 September 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Sep 16 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 259 Issued at 2200Z on 16 Sep 2011
IA. Analysis of Solar Active Regions and Activity from 15/2100Z
to 16/2100Z: Solar activity remained low. Frequent C-class flares
were observed during the period. The largest was a C9/Sf at 16/1136Z
from Region 1290 (S13W69). Region 1299 (S21E10) was numbered as a
Cro-beta group with 8 spots today.
IB. Solar Activity Forecast: Solar activity is expected to be low
with a chance for isolated M-class flares during the period (17-19
September).
IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z:
The geomagnetic field was at quiet levels. The greater than 2 MeV
electron flux at geosynchronous orbit was at high levels throughout
the period.
IIB. Geophysical Activity Forecast: Geomagnetic field activity is
expected to be at unsettled to active levels, with isolated minor
storm levels at high latitudes, on day one (17 September), due to
the effects of the full halo CME observed at 14/0000Z. Activity is
expected to decrease to quiet to active levels on day two (18
September). Predominantly quiet levels are expected on day three (19
September).
III. Event Probabilities 17 Sep-19 Sep
Class M 35/35/35
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 16 Sep 143
Predicted 17 Sep-19 Sep 142/140/140
90 Day Mean 16 Sep 102
V. Geomagnetic A Indices
Observed Afr/Ap 15 Sep 004/005
Estimated Afr/Ap 16 Sep 007/010
Predicted Afr/Ap 17 Sep-19 Sep 018/020-010/015-005/005
VI. Geomagnetic Activity Probabilities 17 Sep-19 Sep
A. Middle Latitudes
Active 25/25/15
Minor storm 10/15/10
Major-severe storm 01/01/01
B. High Latitudes
Active 30/30/20
Minor storm 20/15/10
Major-severe storm 05/01/01