Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 15 September 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 258 Issued at 2200Z on 15 Sep 2015

IA. Analysis of Solar Active Regions and Activity from 14/2100Z to 15/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C1 event observed at 15/0519Z from Region 2415 (S22E14). There are currently 4 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 (16 Sep, 17 Sep, 18 Sep).

IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z: The geomagnetic field has been at unsettled to active levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 567 km/s at 15/1324Z. Total IMF reached 8 nT at 15/0427Z. The maximum southward component of Bz reached -5 nT at 15/0738Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 6437 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (16 Sep) and quiet to unsettled levels on days two and three (17 Sep, 18 Sep).

III. Event probabilities 16 Sep-18 Sep
Class M 05/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 15 Sep 101
Predicted 16 Sep-18 Sep 100/100/095
90 Day Mean 15 Sep 105

V. Geomagnetic A Indices
Observed Afr/Ap 14 Sep 010/016
Estimated Afr/Ap 15 Sep 014/018
Predicted Afr/Ap 16 Sep-18 Sep 009/012-008/008-008/008

VI. Geomagnetic Activity Probabilities 16 Sep-18 Sep
A. Middle Latitudes
Active 30/20/20
Minor Storm 15/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/20
Minor Storm 25/30/30
Major-severe storm 40/25/25