Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 28 June 2021

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 179 Issued at 2200Z on 28 Jun 2021

IA. Analysis of Solar Active Regions and Activity from 27/2100Z to 28/2100Z: 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 28/0935Z from Region 2836 (S28E21). 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 (29 Jun, 30 Jun, 01 Jul).

IIA. Geophysical Activity Summary 27/2100Z to 28/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed reached a peak of 384 km/s at 27/2340Z. Total IMF reached 5 nT at 28/0105Z. The maximum southward component of Bz reached -3 nT at 27/2231Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 343 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on day one (29 Jun) and quiet to unsettled levels on days two and three (30 Jun, 01 Jul).

III. Event probabilities 29 Jun-01 Jul
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 28 Jun 089
Predicted 29 Jun-01 Jul 090/090/090
90 Day Mean 28 Jun 077

V. Geomagnetic A Indices
Observed Afr/Ap 27 Jun 004/005
Estimated Afr/Ap 28 Jun 003/004
Predicted Afr/Ap 29 Jun-01 Jul 005/005-008/010-008/010

VI. Geomagnetic Activity Probabilities 29 Jun-01 Jul
A. Middle Latitudes
Active 10/15/20
Minor Storm 01/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor Storm 20/25/25
Major-severe storm 10/25/30