Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 357 Issued at 2200Z on 23 Dec 2014
IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C5 event observed at 22/2225Z from Region 2241 (S10W47). There are currently 8 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 day one (24 Dec) and likely to be moderate with a slight chance for an X-class flare on days two and three (25 Dec, 26 Dec).
IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 542 km/s at 23/1036Z. Total IMF reached 34 nT at 23/1040Z. The maximum southward component of Bz reached -15 nT at 23/2001Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 14 pfu at 23/1115Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to minor storm levels on day one (24 Dec), quiet to unsettled levels on day two (25 Dec) and quiet levels on day three (26 Dec). Protons have a slight chance of crossing threshold on day one (24 Dec) and have a slight chance of crossing threshold on days two and three (25 Dec, 26 Dec).
III. Event probabilities 24 Dec-26 Dec
Class M 75/60/60
Class X 25/20/15
Proton 20/10/10
PCAF green
IV. Penticton 10.7 cm Flux
Observed 23 Dec 166
Predicted 24 Dec-26 Dec 160/155/150
90 Day Mean 23 Dec 159
V. Geomagnetic A Indices
Observed Afr/Ap 22 Dec 013/016
Estimated Afr/Ap 23 Dec 010/014
Predicted Afr/Ap 24 Dec-26 Dec 012/016-007/015-006/008
VI. Geomagnetic Activity Probabilities 24 Dec-26 Dec
