Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 51 Issued at 2200Z on 20 Feb 2015
IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 20/1522Z. There are currently 4 numbered sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (21 Feb, 22 Feb, 23 Feb).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: 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 409 km/s at 19/2232Z. Total IMF reached 6 nT at 20/2054Z. The maximum southward component of Bz reached -5 nT at 20/0727Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 774 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (21 Feb), quiet to active levels on day two (22 Feb) and unsettled levels on day three (23 Feb).
III. Event probabilities 21 Feb-23 Feb
Class M 01/01/01
Class X 01/01/01
IV. Penticton 10.7 cm Flux
Observed 20 Feb 120
Predicted 21 Feb-23 Feb 120/125/125
90 Day Mean 20 Feb 149
V. Geomagnetic A Indices
Observed Afr/Ap 19 Feb 005/007
Estimated Afr/Ap 20 Feb 006/005
Predicted Afr/Ap 21 Feb-23 Feb 007/008-012/015-011/012
VI. Geomagnetic Activity Probabilities 21 Feb-23 Feb