Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 March 2013
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 75 Issued at 2200Z on 16 Mar 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
16/0539Z from Region 1698 (S19W57). There are currently 6 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (17
Mar, 18 Mar, 19 Mar).
IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
551 km/s at 16/0506Z. Total IMF reached 7 nT at 16/0257Z. The maximum
southward component of Bz reached -6 nT at 16/0309Z. Protons greater
than 10 MeV at geosynchronous orbit reached a peak level of 12 pfu at
16/2015Z.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to major storm levels on day one (17 Mar), quiet to
active levels on day two (18 Mar) and quiet levels on day three (19
Mar). Protons are expected to cross threshold on day one (17 Mar), are
likely to cross threshold on day two (18 Mar) and have a chance of
crossing threshold on day three (19 Mar).
III. Event probabilities 17 Mar-19 Mar
Class M 20/20/20
Class X 01/01/01
Proton 75/60/25
PCAF yellow
IV. Penticton 10.7 cm Flux
Observed 16 Mar 126
Predicted 17 Mar-19 Mar 125/120/115
90 Day Mean 16 Mar 116
V. Geomagnetic A Indices
Observed Afr/Ap 15 Mar 005/005
Estimated Afr/Ap 16 Mar 012/015
Predicted Afr/Ap 17 Mar-19 Mar 028/039-014/020-006/005
VI. Geomagnetic Activity Probabilities 17 Mar-19 Mar
A. Middle Latitudes
Active 30/30/05
Minor Storm 35/10/01
Major-severe storm 20/01/01
B. High Latitudes
Active 05/15/15
Minor Storm 20/30/10
Major-severe storm 70/40/05
