Joint USAF/NOAA Report of Solar and Geophysical Activity 03 May 2005

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.

Updated 2005 May 03 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 123 Issued at 2200Z on 03 May 2005

IA. Analysis of Solar Active Regions and Activity from 02/2100Z
to 03/2100Z: Solar activity was low. Region 758 (S07E63) was
responsible for a long duration C8 flare at 02/2248 UTC and an
associated CME. A very bright post eruption arcade was visible on
SXI and EIT imagery. Region 758’s limb proximity is hindering a
full analysis, however, it appears to be a moderately complex
beta-gamma group. Later in the day, a partial halo CME was observed
on LASCO imagery at 03/1750 UTC. This is another in a series of
backsided CME’s that have occurred since 30 April. None of the
CME’s are expected to be geoeffective.

IB. Solar Activity Forecast: Solar activity is expected to be low
with the chance for an isolated M-flare from Regions 756 (S07W38) or
758.

IIA. Geophysical Activity Summary 02/2100Z to 03/2100Z:
The geomagnetic field was quiet to unsettled. The greater than 2 MeV
electron flux at geosynchronous orbit reached high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled.

III. Event Probabilities 04 May-06 May

• Class M 30/30/30
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 03 May 112
• Predicted 04 May-06 May 110/110/105
• 90 Day Mean 03 May 092

V. Geomagnetic A Indices

• Observed Afr/Ap 02 May 006/007
• Estimated Afr/Ap 03 May 008/010
• Predicted Afr/Ap 04 May-06 May 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 04 May-06 May

A. Middle Latitudes

• Active 15/15/15
• Minor storm 05/05/05
• Major-severe storm 01/01/01

B. High Latitudes

• Active 15/15/15
• Minor storm 05/05/05
• Major-severe storm 01/01/01