Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 18 July 2017
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 199 Issued at 2200Z on 18 Jul 2017
IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 18/0040Z from old Region 2665 – now around the West limb. There are currently no 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 (19 Jul) and expected to be very low on days two and three (20 Jul, 21 Jul).
IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed averaged near 550 km/s. Total IMF reached 10 nT at 18/0357Z. The maximum southward component of Bz reached -8 nT at 18/0055Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 5531 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels on days one and two (19 Jul, 20 Jul) and quiet to active levels on day three (21 Jul).
III. Event probabilities 19 Jul-21 Jul
Class M 05/01/01
Class X 01/01/01
Proton 05/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 18 Jul 078
Predicted 19 Jul-21 Jul 075/075/075
90 Day Mean 18 Jul 077
V. Geomagnetic A Indices
Observed Afr/Ap 17 Jul 023/033
Estimated Afr/Ap 18 Jul 009/010
Predicted Afr/Ap 19 Jul-21 Jul 008/008-007/008-009/012
VI. Geomagnetic Activity Probabilities 19 Jul-21 Jul
A. Middle Latitudes
Active 20/20/30
Minor Storm 05/05/10
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/25/25
Major-severe storm 30/30/40