- Press Release
- Sep 26, 2022
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 4 February 2013
Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 35 Issued at 2200Z on 04 Feb 2013
IA. Analysis of Solar Active Regions and Activity from 03/2100Z to
04/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C2/Sf flare with an
associated Type II (estimated velocity of 849 km/s) observed at 04/1459Z
from an unnumbered region that recently rotated around the eastern limb.
This region was not numbered due to the close proximity to the limb.
There are currently 2 numbered sunspot regions on the disk and no
Earth-directed coronal mass ejections expected.
IB. Solar Activity Forecast: Solar activity is expected to be at low
levels on days one, two, and three (05 Feb, 06 Feb, 07 Feb).
IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 439 km/s at
03/2108Z. Total IMF reached 6 nT at 04/1630Z. The maximum southward
component of Bz reached -3.8 nT at 04/1632Z. Electrons greater than 2
MeV at geosynchronous orbit reached a peak level of 204 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels for the next three days (05 Feb, 06 Feb, 07 Feb).
III. Event probabilities 05 Feb-07 Feb
Class M 10/10/10
Class X 01/01/01
IV. Penticton 10.7 cm Flux
Observed 04 Feb 107
Predicted 05 Feb-07 Feb 105/105/105
90 Day Mean 04 Feb 120
V. Geomagnetic A Indices
Observed Afr/Ap 03 Feb 006/002
Estimated Afr/Ap 04 Feb 003/004
Predicted Afr/Ap 05 Feb-07 Feb 006/005-006/005-006/005
VI. Geomagnetic Activity Probabilities 05 Feb-07 Feb
A. Middle Latitudes
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Minor Storm 15/15/15
Major-severe storm 10/10/10