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

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 172 Issued at 2200Z on 21 Jun 2017

IA.  Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 3 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on days one, two, and three (22 Jun, 23 Jun, 24 Jun).

IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed averaged 340 km/s. Total IMF reached 6 nT at 21/1711Z. The maximum southward component of Bz reached -5 nT at 21/1759Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3097 pfu.

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

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

IV.  Penticton 10.7 cm Flux
Observed           21 Jun 074
Predicted   22 Jun-24 Jun 075/075/075
90 Day Mean        21 Jun 077

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Jun  003/003
Estimated Afr/Ap 21 Jun  004/005
Predicted Afr/Ap 22 Jun-24 Jun  006/008-008/012-010/012

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