Report of Solar-Geophysical Activity

Issued: 2006 Apr 30 2200 UTC

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

Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 120 Issued at 2200Z on 30 Apr 2006 IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity was low. New Region 878 (N14E60) produced a C5/sf at 30/0157Z. A Tenflare (110 sfu) and a Type II radio sweep, with an estimated shock speed of 657 Km/sec, were associated with this flare. An associated CME was observed off the east limb on LASCO imagery at 30/0142Z. Region 876 (S11E08) produced a C1/sf flare at 30/0932Z. A Type II radio sweep, with an estimated shock speed of 822 Km/sec, was associated with this flare.

IB. Solar Activity Forecast: Solar activity is expected to be low.

M-class flare activity remains possible.

IIA. Geophysical Activity Summary 29/2100Z to 30/2100Z:

The geomagnetic field was quiet.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet on 1 May. Predominantly unsettled conditions will occur on 2 May. Expect quiet to unsettled conditions on 3 May.

III. Event Probabilities 01 May-03 May

Class M 25/25/25

Class X 05/05/05

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 30 Apr 100

Predicted 01 May-03 May 105/105/105

90 Day Mean 30 Apr 081

V. Geomagnetic A Indices

Observed Afr/Ap 29 Apr 002/003

Estimated Afr/Ap 30 Apr 002/005

Predicted Afr/Ap 01 May-03 May 005/007-012/015-005/010 VI. Geomagnetic Activity Probabilities 01 May-03 May A. Middle Latitudes

Active 10/20/10

Minor storm 05/10/05

Major-severe storm 01/05/01

B. High Latitudes

Active 15/20/15

Minor storm 05/15/05

Major-severe storm 01/05/01