Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 21 June 2018

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 172 Issued at 2200Z on 21 Jun 2018

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 C2 event observed at 21/0115Z from Region 2715 (N08E06). 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 Jun, 23 Jun, 24 Jun).

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 reached a peak of 441 km/s at 21/1554Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 206 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one and two (22 Jun, 23 Jun) and quiet to active levels on day three (24 Jun).

III.  Event probabilities 22 Jun-24 Jun
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           21 Jun 082
Predicted   22 Jun-24 Jun 082/080/080
90 Day Mean        21 Jun 071

V.  Geomagnetic A Indices
Observed Afr/Ap 20 Jun  007/006
Estimated Afr/Ap 21 Jun  004/004
Predicted Afr/Ap 22 Jun-24 Jun  006/005-006/005-011/012

VI.  Geomagnetic Activity Probabilities 22 Jun-24 Jun
A.  Middle Latitudes
Active                10/10/30
Minor Storm           01/01/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           20/20/25
Major-severe storm    15/10/40