Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 April 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 106 Issued at 2200Z on 16 Apr 2013

IA. Analysis of Solar Active Regions and Activity from 15/2100Z to
16/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
16/1646Z from Region 1719 (N09W64). There are currently 5 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (17
Apr, 18 Apr, 19 Apr).

IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: 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 420 km/s at
16/0041Z. Total IMF reached 6 nT at 15/2247Z. The maximum southward
component of Bz reached -4 nT at 15/2121Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one, two, and three (17 Apr, 18 Apr, 19
Apr).

III. Event probabilities 17 Apr-19 Apr
Class M 15/15/15
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 16 Apr 113
Predicted 17 Apr-19 Apr 105/100/100
90 Day Mean 16 Apr 111

V. Geomagnetic A Indices
Observed Afr/Ap 15 Apr 006/006
Estimated Afr/Ap 16 Apr 003/003
Predicted Afr/Ap 17 Apr-19 Apr 005/005-004/005-006/005

VI. Geomagnetic Activity Probabilities 17 Apr-19 Apr
A. Middle Latitudes
Active 10/10/10
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 15/15/15
Major-severe storm 05/10/10