Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 27 March 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 86 Issued at 2200Z on 27 Mar 2013

IA. Analysis of Solar Active Regions and Activity from 26/2100Z to
27/2100Z: Solar activity has been at very low levels for the past 24
hours. 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 (28 Mar,
29 Mar, 30 Mar).

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z: 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
545 km/s at 27/2018Z. Total IMF reached 12 nT at 27/0836Z. The maximum
southward component of Bz reached -8 nT at 27/1447Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 1163 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active with a chance of minor storm levels on day one
(28 Mar), unsettled to active levels on day two (29 Mar) and quiet to
unsettled levels on day three (30 Mar).

III. Event probabilities 28 Mar-30 Mar
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 Mar 093
Predicted 28 Mar-30 Mar 095/100/105
90 Day Mean 27 Mar 115

V. Geomagnetic A Indices
Observed Afr/Ap 26 Mar 002/002
Estimated Afr/Ap 27 Mar 009/013
Predicted Afr/Ap 28 Mar-30 Mar 015/022-015/018-007/008

VI. Geomagnetic Activity Probabilities 28 Mar-30 Mar
A. Middle Latitudes
Active 40/35/15
Minor Storm 20/15/05
Major-severe storm 05/01/01
B. High Latitudes
Active 10/15/15
Minor Storm 30/20/20
Major-severe storm 60/20/10