Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 21 January 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 21 Issued at 2200Z on 21 Jan 2017

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C9 event observed at 21/0726Z from Region 2628 (N12E36). There are currently 4 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is likely to be low with a chance for M-class flares on days one, two, and three (22 Jan, 23 Jan, 24 Jan).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 536 km/s at 20/2126Z. Total IMF reached 6 nT at 21/1541Z. The maximum southward component of Bz reached -4 nT at 21/0512Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 2839 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on day one (22 Jan) and quiet levels on days two and three (23 Jan, 24 Jan).

III.  Event probabilities 22 Jan-24 Jan
Class M    25/25/25
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Jan 086
Predicted   22 Jan-24 Jan 085/085/082
90 Day Mean        21 Jan 077

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Jan  009/007
Estimated Afr/Ap 21 Jan  007/009
Predicted Afr/Ap 22 Jan-24 Jan  007/008-006/005-006/005

VI.  Geomagnetic Activity Probabilities 22 Jan-24 Jan
A.  Middle Latitudes
Active                10/05/05
Minor Storm           01/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                20/15/15
Minor Storm           25/20/20
Major-severe storm    15/10/10