Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 August 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 228 Issued at 2200Z on 16 Aug 2013

IA. Analysis of Solar Active Regions and Activity from 15/2100Z to
16/2100Z: 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
15/2216Z from Region 1817 (S21W44). There are currently 6 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 (17 Aug, 18 Aug,
19 Aug).

IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet to minor storm levels for the past 24 hours.
Solar wind speed, as measured by the ACE spacecraft, reached a peak
speed of 860 km/s at 16/1145Z. Total IMF reached 9 nT at 15/2349Z. The
maximum southward component of Bz reached -8 nT at 16/0244Z. Electrons
greater than 2 MeV at geosynchronous orbit reached a peak level of 1355
pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (17 Aug) and quiet to
unsettled levels on days two and three (18 Aug, 19 Aug).

III. Event probabilities 17 Aug-19 Aug
Class M 35/35/35
Class X 05/05/05
Proton 05/05/05
PCAF green

IV. Penticton 10.7 cm Flux
Observed 16 Aug 120
Predicted 17 Aug-19 Aug 125/130/130
90 Day Mean 16 Aug 114

V. Geomagnetic A Indices
Observed Afr/Ap 15 Aug 015/016
Estimated Afr/Ap 16 Aug 017/023
Predicted Afr/Ap 17 Aug-19 Aug 012/015-011/012-008/005

VI. Geomagnetic Activity Probabilities 17 Aug-19 Aug
A. Middle Latitudes
Active 45/20/10
Minor Storm 10/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 10/15/20
Minor Storm 30/30/30
Major-severe storm 50/30/15