Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 18 March 2013
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 77 Issued at 2200Z on 18 Mar 2013
IA. Analysis of Solar Active Regions and Activity from 17/2100Z to
18/2100Z: 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
18/0321Z from Region 1698 (S19W86). 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 and two (19 Mar, 20
Mar) and expected to be very low with a chance for a C-class flares and
a slight chance for an M-class flare on day three (21 Mar).
IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: 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 702 km/s at 18/0049Z. Total IMF reached 11 nT at 17/2106Z. The
maximum southward component of Bz reached -5 nT at 17/2112Z. Protons
greater than 10 MeV at geosynchronous orbit reached a peak level of 2
pfu at 17/2105Z. Electrons greater than 2 MeV at geosynchronous orbit
reached a peak level of 253 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (19 Mar, 20 Mar)
and quiet to active levels on day three (21 Mar).
III. Event probabilities 19 Mar-21 Mar
Class M 20/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green
IV. Penticton 10.7 cm Flux
Observed 18 Mar 118
Predicted 19 Mar-21 Mar 115/110/105
90 Day Mean 18 Mar 116
V. Geomagnetic A Indices
Observed Afr/Ap 17 Mar 032/057
Estimated Afr/Ap 18 Mar 010/011
Predicted Afr/Ap 19 Mar-21 Mar 009/008-008/008-008/010
VI. Geomagnetic Activity Probabilities 19 Mar-21 Mar
A. Middle Latitudes
Active 15/15/25
Minor Storm 05/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/20/30
Major-severe storm 20/20/30
