Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 28 July 2017

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 209 Issued at 2200Z on 28 Jul 2017

IA.  Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: 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 on day one (29 Jul) and expected to be very low with a chance for a C-class flares on day two (30 Jul) and expected to be very low with a chance for a C-class flares and a slight chance for an M-class flare on day three (31 Jul).

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 492 km/s at 28/1110Z. Total IMF reached 5 nT at 27/2119Z. The maximum southward component of Bz reached -5 nT at 27/2123Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 14317 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (29 Jul, 30 Jul) and quiet to active levels on day three (31 Jul).

III.  Event probabilities 29 Jul-31 Jul
Class M    01/05/10
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           28 Jul 070
Predicted   29 Jul-31 Jul 072/080/082
90 Day Mean        28 Jul 076

V.  Geomagnetic A Indices
Observed Afr/Ap 27 Jul  008/007
Estimated Afr/Ap 28 Jul  006/008
Predicted Afr/Ap 29 Jul-31 Jul  005/005-006/005-010/012

VI.  Geomagnetic Activity Probabilities 29 Jul-31 Jul
A.  Middle Latitudes
Active                10/10/25
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    10/10/40