Report of Solar-Geophysical Activity

Issued: 2006 May 10 2212 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 130 Issued at 2200Z on 10 May 2006 IA. Analysis of Solar Active Regions and Activity from 09/2100Z to 10/2100Z: Solar activity was very low. Region 882 (S12W70) showed no change this period, and produced no significant activity. Region 880 (S09W17), the only other region with sunspots on the visible disk, was stable.

IB. Solar Activity Forecast: Solar activity is expected to continue at very low levels.

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z:

The geomagnetic field was quiet. The large recurrent coronal hole high speed stream is now rotating into a geoeffective position.

Enhancements were observed in both the solar wind plasma and interplanetary magnetic field measurements. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from quiet to major storm levels. A recurrent coronal hole is rotating into a geoeffective position. Expect active to minor storm periods on 11 and 12 May. Isolated major storm periods are possible on both days. Quiet to unsettled levels, with occasional active periods are expected on 13 May.

III. Event Probabilities 11 May-13 May

Class M 01/01/01

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 10 May 078

Predicted 11 May-13 May 075/075/075

90 Day Mean 10 May 082

V. Geomagnetic A Indices

Observed Afr/Ap 09 May 002/004

Estimated Afr/Ap 10 May 005/010

Predicted Afr/Ap 11 May-13 May 025/030-020/025-010/012 VI. Geomagnetic Activity Probabilities 11 May-13 May A. Middle Latitudes

Active 50/50/25

Minor storm 25/25/10

Major-severe storm 15/15/05

B. High Latitudes

Active 50/50/30

Minor storm 30/30/15

Major-severe storm 20/20/10