Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 July 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 201 Issued at 2200Z on 20 Jul 2017

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 0 numbered sunspot regions on the disk.

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

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 reached a peak of 506 km/s at 20/2037Z. Total IMF reached 10 nT at 20/1650Z. The maximum southward component of Bz reached -8 nT at 20/1757Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 11443 pfu.

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

III.  Event probabilities 21 Jul-23 Jul
Class M    05/01/01
Class X    01/01/01
Proton     05/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           20 Jul 070
Predicted   21 Jul-23 Jul 070/070/070
90 Day Mean        20 Jul 076

V.  Geomagnetic A Indices
Observed Afr/Ap 19 Jul  005/003
Estimated Afr/Ap 20 Jul  006/005
Predicted Afr/Ap 21 Jul-23 Jul  008/008-009/012-007/008

VI.  Geomagnetic Activity Probabilities 21 Jul-23 Jul
A.  Middle Latitudes
Active                25/30/10
Minor Storm           10/15/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/10/15
Minor Storm           25/25/20
Major-severe storm    40/50/15