Joint USAF/NOAA Report of Solar and Geophysical Activity 27 Mar 2004
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2004 Mar 27 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 087 Issued at 2200Z on 27 Mar 2004
IA. Analysis of Solar Active Regions and Activity from 26/2100Z
to 27/2100Z: Solar activity was low. Newly assigned Region 586
(S18W80) produced four, low-level C-class flares during the past 24
hours. Region 582 (N14E45) continues to be the largest group on the
disk but was quiet.
IB. Solar Activity Forecast: Solar activity is expected to be low.
There is a slight chance for an isolated M-class event, with Region
582 being the most likely source.
IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was mostly unsettled to active. Solar wind data
show the continuation and intensification of the high speed stream.
The velocity increased from around 600 km/s up to about 900 km/s
between 1500Z and 2100Z. At the same time density decreased,
temperature increased, and Alfven wave activity in the magnetic
field components appeared to increase.
IIB. Geophysical Activity Forecast: The geomagnetic field should be
mostly unsettled to active for the next three days (27-29 March) as
the high speed stream is likely to persist.
III. Event Probabilities 28 Mar-30 Mar
- Class M 20/20/20
- Class X 05/05/05
- Proton 05/05/05
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 27 Mar 128
- Predicted 28 Mar-30 Mar 125/120/115
- 90 Day Mean 27 Mar 110
V. Geomagnetic A Indices
- Observed Afr/Ap 26 Mar 010/011
- Estimated Afr/Ap 27 Mar 015/015
- Predicted Afr/Ap 28 Mar-30 Mar 015/018-015/018-015/015
VI. Geomagnetic Activity Probabilities 28 Mar-30 Mar
A. Middle Latitudes
- Active 30/30/30
- Minor storm 25/25/25
- Major-severe storm 10/10/10
B. High Latitudes
- Active 35/35/35
- Minor storm 20/20/20
- Major-severe storm 15/15/15
