Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 140 Issued at 2200Z on 20 May 2015
IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: 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 20/0812Z from Region 2349 (S21E04). 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 (21 May, 22 May, 23 May).
IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: 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 652 km/s at 20/0410Z. Total IMF reached 7 nT at 20/1543Z. The maximum southward component of Bz reached -5 nT at 20/0001Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 125 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (21 May, 22 May, 23 May).
III. Event probabilities 21 May-23 May
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 20 May 106
Predicted 21 May-23 May 105/100/100
90 Day Mean 20 May 128
V. Geomagnetic A Indices
Observed Afr/Ap 19 May 014/018
Estimated Afr/Ap 20 May 008/010
Predicted Afr/Ap 21 May-23 May 006/005-006/005-006/005
VI. Geomagnetic Activity Probabilities 21 May-23 May
