Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 141 Issued at 2200Z on 21 May 2015
IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: 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 21/0706Z from Region 2349 (S21W10). 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 (22 May, 23 May, 24 May).
IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 468 km/s at 21/1022Z. Total IMF reached 6 nT at 20/2106Z. The maximum southward component of Bz reached -3 nT at 21/1130Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 146 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (22 May, 23 May, 24 May).
III. Event probabilities 22 May-24 May
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 21 May 102
Predicted 22 May-24 May 100/100/100
90 Day Mean 21 May 128
V. Geomagnetic A Indices
Observed Afr/Ap 20 May 010/009
Estimated Afr/Ap 21 May 003/004
Predicted Afr/Ap 22 May-24 May 006/005-006/005-006/005
VI. Geomagnetic Activity Probabilities 22 May-24 May
