Joint USAF/NOAA Report of Solar and Geophysical Activity 27 Feb 2005
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 Feb 27 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 058 Issued at 2200Z on 27 Feb 2005
IA. Analysis of Solar Active Regions and Activity from 26/2100Z
to 27/2100Z: Solar activity continues at very low levels. Region 739
(S04E38) is a small and magnetically simple sunspot group, and is
the only spot group on the visible disk. A section of a large
prominence erupted off the southwest limb at around 27/1000Z. The
associated CME on LASCO imagery does not appear to be Earth
directed. Little else of significance was observed.
IB. Solar Activity Forecast: Solar activity is expected to continue
at very low levels.
IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was quiet to unsettled with isolated active
periods. The disturbed periods are due to a large transequatorial
coronal hole, which is producing solar wind speeds generally ranging
between 500 – 600 km/s.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled with isolated active periods on 28
February and 01 March. Quiet, with occasional unsettled periods are
expected on 02 March as the coronal hole high speed stream rotates
out of a geoeffective position.
III. Event Probabilities 28 Feb-02 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 Feb 076
- Predicted 28 Feb-02 Mar 075/075/075
- 90 Day Mean 27 Feb 098
V. Geomagnetic A Indices
- Observed Afr/Ap 26 Feb 009/009
- Estimated Afr/Ap 27 Feb 010/012
- Predicted Afr/Ap 28 Feb-02 Mar 010/020-008/012-005/010
VI. Geomagnetic Activity Probabilities 28 Feb-02 Mar
A. Middle Latitudes
- Active 25/20/15
- Minor storm 15/10/01
- Major-severe storm 05/01/01
B. High Latitudes
- Active 30/25/25
- Minor storm 20/15/15
- Major-severe storm 10/05/05
