Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 30 April 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 120 Issued at 2200Z on 30 Apr 2013

IA. Analysis of Solar Active Regions and Activity from 29/2100Z to
30/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C3 event observed at
29/2201Z from Region 1731 (N09E11). There are currently 7 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 (01 May, 02 May,
03 May).

IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 451 km/s at
30/1415Z. Total IMF reached 10 nT at 30/1402Z. The maximum southward
component of Bz reached -5 nT at 30/0940Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 1972 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one and three (01 May, 03 May) and quiet
to unsettled levels on day two (02 May).

III. Event probabilities 01 May-03 May
Class M 40/40/40
Class X 05/05/05
Proton 05/05/05
PCAF green

IV. Penticton 10.7 cm Flux
Observed 30 Apr 154
Predicted 01 May-03 May 155/160/165
90 Day Mean 30 Apr 114

V. Geomagnetic A Indices
Observed Afr/Ap 29 Apr 005/004
Estimated Afr/Ap 30 Apr 007/007
Predicted Afr/Ap 01 May-03 May 004/005-006/008-004/005

VI. Geomagnetic Activity Probabilities 01 May-03 May
A. Middle Latitudes
Active 10/15/05
Minor Storm 01/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 15/25/10
Major-severe storm 10/20/05