Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 354 Issued at 2200Z on 20 Dec 2014
IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at high levels for the past 24 hours. The largest solar event of the period was a X1 event observed at 20/0028Z from Region 2242 (S19W44). There are currently 7 numbered sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be moderate with a chance for X-class flares on days one, two, and three (21 Dec, 22 Dec, 23 Dec).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: 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 406 km/s at 19/2212Z. Total IMF reached 7 nT at 20/1840Z. The maximum southward component of Bz reached -6 nT at 20/0259Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 388 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to major storm levels on day one (21 Dec), quiet to minor storm levels on day two (22 Dec) and quiet to unsettled levels on day three (23 Dec). Protons have a chance of crossing threshold on days one, two, and three (21 Dec, 22 Dec, 23 Dec).
III. Event probabilities 21 Dec-23 Dec
Class M 85/85/85
Class X 40/40/40
Proton 30/30/30
PCAF green
IV. Penticton 10.7 cm Flux
Observed 20 Dec 203
Predicted 21 Dec-23 Dec 205/205/200
90 Day Mean 20 Dec 157
V. Geomagnetic A Indices
Observed Afr/Ap 19 Dec 006/006
Estimated Afr/Ap 20 Dec 008/008
Predicted Afr/Ap 21 Dec-23 Dec 022/035-015/018-007/008
VI. Geomagnetic Activity Probabilities 21 Dec-23 Dec
