Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 31 July 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 212 Issued at 2200Z on 31 Jul 2015

IA. Analysis of Solar Active Regions and Activity from 30/2100Z to 31/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 5 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 days one, two, and three (01 Aug, 02 Aug, 03 Aug).

IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 640 km/s at 31/1832Z. Total IMF reached 15 nT at 30/2132Z. The maximum southward component of Bz reached -10 nT at 31/1153Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (01 Aug), unsettled to active levels on day two (02 Aug) and unsettled levels on day three (03 Aug).

III. Event probabilities 01 Aug-03 Aug
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 31 Jul 101
Predicted 01 Aug-03 Aug 105/105/105
90 Day Mean 31 Jul 117

V. Geomagnetic A Indices
Observed Afr/Ap 30 Jul 012/013
Estimated Afr/Ap 31 Jul 013/017
Predicted Afr/Ap 01 Aug-03 Aug 020/024-012/016-011/012

VI. Geomagnetic Activity Probabilities 01 Aug-03 Aug
A. Middle Latitudes
Active 40/30/15
Minor Storm 20/10/05
Major-severe storm 05/01/01
B. High Latitudes
Active 10/15/20
Minor Storm 30/30/30
Major-severe storm 55/40/25