Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.
Updated 2011 May 02 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 122 Issued at 2200Z on 02 May 2011

IA. Analysis of Solar Active Regions and Activity from 01/2100Z
to 02/2100Z: Solar activity was low. A filament disappeared from
S20E33 around 14Z. A concurrent CME was visible leaving off the east
limb based on the NASA SOHO LASCO C2 coronagraph, though it does not
initially appear that it will be geoeffective.

IB. Solar Activity Forecast: Solar activity is expected to be very
low to low for the next 3 days (3-5 May).

IIA. Geophysical Activity Summary 01/2100Z to 02/2100Z:
The geomagnetic field ranged from unsettled to minor storm conditions
due to coronal hole (CH) high-speed stream effects (HSS). Solar
winds speeds were sustained above 640 km/s during the period. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels during the period.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be unsettled to active on day 1 (3 May) as CH HSS
effects wane. Mostly quiet conditions are forecasted for days 2 and
3 (4-5 May).

III. Event Probabilities 03 May-05 May
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 02 May 110
Predicted 03 May-05 May 110/110/110
90 Day Mean 02 May 108

V. Geomagnetic A Indices
Observed Afr/Ap 01 May 013/019
Estimated Afr/Ap 02 May 010/018
Predicted Afr/Ap 03 May-05 May 008/012-005/008-005/005

VI. Geomagnetic Activity Probabilities 03 May-05 May
A. Middle Latitudes
Active 40/20/20
Minor storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 60/30/20
Minor storm 20/01/01
Major-severe storm 05/01/01