Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 18 August 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 230 Issued at 2200Z on 18 Aug 2015

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: 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 chance for a C-class flares on days one, two, and three (19 Aug, 20 Aug, 21 Aug).

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, as measured by the ACE spacecraft, reached a peak speed of 638 km/s at 18/0017Z. Total IMF reached 6 nT at 18/2050Z. The maximum southward component of Bz reached -4 nT at 18/2014Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 21632 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (19 Aug) and quiet levels on days two and three (20 Aug, 21 Aug).

III. Event probabilities 19 Aug-21 Aug
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 18 Aug 089
Predicted 19 Aug-21 Aug 090/095/095
90 Day Mean 18 Aug 110

V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 027/031
Estimated Afr/Ap 18 Aug 012/013
Predicted Afr/Ap 19 Aug-21 Aug 009/010-006/005-006/005

VI. Geomagnetic Activity Probabilities 19 Aug-21 Aug
A. Middle Latitudes
Active 35/10/10
Minor Storm 10/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 30/20/20
Major-severe storm 45/15/15