Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 September 2016

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 264 Issued at 2200Z on 20 Sep 2016

IA.  Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low with a chance for C-class flares on days one, two, and three (21 Sep, 22 Sep, 23 Sep).

IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 751 km/s at 20/1106Z. Total IMF reached 19 nT at 19/2243Z. The maximum southward component of Bz reached -13 nT at 20/0023Z.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (21 Sep) and quiet to unsettled levels on days two and three (22 Sep, 23 Sep).

III.  Event probabilities 21 Sep-23 Sep
Class M    01/01/01
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 Sep 085
Predicted   21 Sep-23 Sep 082/080/080
90 Day Mean        20 Sep 085

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Sep  008/010
Estimated Afr/Ap 20 Sep  015/020
Predicted Afr/Ap 21 Sep-23 Sep  010/012-007/008-007/008

VI.  Geomagnetic Activity Probabilities 21 Sep-23 Sep
A.  Middle Latitudes
Active                15/15/25
Minor Storm           01/01/05
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/30
Major-severe storm    20/20/35