Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 15 April 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 105 Issued at 2200Z on 15 Apr 2013

IA. Analysis of Solar Active Regions and Activity from 14/2100Z to
15/2100Z: 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
15/1403Z from Region 1723 (S18E20). There are currently 6 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 day one (16 Apr) and expected to be low
with a slight chance for an M-class flare on day two (17 Apr) and likely
to be low on day three (18 Apr).

IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
541 km/s at 14/2245Z. Total IMF reached 12 nT at 14/2153Z. The maximum
southward component of Bz reached -4 nT at 15/2058Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one, two, and three (16 Apr, 17 Apr, 18
Apr).

III. Event probabilities 16 Apr-18 Apr
Class M 25/15/05
Class X 05/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 15 Apr 113
Predicted 16 Apr-18 Apr 110/105/100
90 Day Mean 15 Apr 112

V. Geomagnetic A Indices
Observed Afr/Ap 14 Apr 010/010
Estimated Afr/Ap 15 Apr 005/005
Predicted Afr/Ap 16 Apr-18 Apr 005/005-005/005-004/005

VI. Geomagnetic Activity Probabilities 16 Apr-18 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 20/15/15
Major-severe storm 10/05/10