Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 20 June 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 171 Issued at 2200Z on 20 Jun 2013

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
20/0920Z from Region 1777 (S16E66). There are currently 7 numbered
sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (21 Jun, 22 Jun,
23 Jun).

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
493 km/s at 20/2000Z. Total IMF reached 15 nT at 20/1839Z. The maximum
southward component of Bz reached -11 nT at 20/1839Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to minor storm levels on day one (21 Jun), quiet to
active levels on day two (22 Jun) and quiet to unsettled levels on day
three (23 Jun).

III. Event probabilities 21 Jun-23 Jun
Class M 30/30/30
Class X 05/05/05
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 20 Jun 126
Predicted 21 Jun-23 Jun 130/135/135
90 Day Mean 20 Jun 121

V. Geomagnetic A Indices
Observed Afr/Ap 19 Jun 004/005
Estimated Afr/Ap 20 Jun 008/010
Predicted Afr/Ap 21 Jun-23 Jun 020/025-013/015-010/010

VI. Geomagnetic Activity Probabilities 21 Jun-23 Jun
A. Middle Latitudes
Active 45/30/20
Minor Storm 25/10/05
Major-severe storm 05/01/01
B. High Latitudes
Active 05/15/15
Minor Storm 25/25/25
Major-severe storm 70/40/25