Joint USAF/NOAA Report of Solar and Geophysical Activity 15 April 2011

:Product: Report of Solar-Geophysical Activity
:Issued: 2011 Apr 15 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 105 Issued at 2200Z on 15 Apr 2011
IA. Analysis of Solar Active Regions and Activity from 14/2100Z
to 15/2100Z: Solar activity increased to moderate levels. Region
1190 (N13W26) produced an M1/1F flare at 15/1712Z. Associated with
this event were discrete radio emissions ranging from 4995 MHz –
15400 MHz. Occasional C-class flares were also observed during the
period. Region 1190 and Region 1193 (N17E44) remain the most
significant regions. Both Regions 1190 and 1193 showed increases in
areal coverage. A filament was observed lifting at 14/2324Z on GOES
SXI. A CME was observed on SOHO/LASCO C2 imagery at 15/0036Z, with a
speed of approximately 390 km/s. STEREO imagery showed the CME is
expected to be geoeffective.
IB. Solar Activity Forecast: Solar activity is expected to be at
low levels, with C-class flares expected for the next three days
(16-18 April). There is also a slight chance for M-class flares
during the period.
IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z:
The geomagnetic field was at quiet levels. 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 predominantly quiet for the next three days (16-18
April).
III. Event Probabilities 16 Apr-18 Apr
Class M 55/55/55
Class X 05/05/05
Proton 05/05/05
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 15 Apr 129
Predicted 16 Apr-18 Apr 135/140/145
90 Day Mean 15 Apr 103
V. Geomagnetic A Indices
Observed Afr/Ap 14 Apr 003/007
Estimated Afr/Ap 15 Apr 003/005
Predicted Afr/Ap 16 Apr-18 Apr 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 16 Apr-18 Apr
A. Middle Latitudes
Active 05/05/05
Minor storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 10/10/10
Minor storm 01/01/01
Major-severe storm 01/01/01