Report of Solar-Geophysical Activity

Issued: 2006 Feb 20 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 051 Issued at 2200Z on 20 Feb 2006 IA. Analysis of Solar Active Regions and Activity from 19/2100Z to 20/2100Z: Solar activity was at very low levels. No significant activity was noted again today. The visible disk remains spotless.

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

IIA. Geophysical Activity Summary 19/2100Z to 20/2100Z:

The geomagnetic field ranged from quiet to major storm levels. An enhancement of the solar wind speed occurred near 20/1000Z (400 km/sec to 550/ km/sec) due to a geoeffective coronal hole. A brief period of major storm levels occurred at higher latitudes between 20/1500 and 1800Z.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on 21 and 22 February, due to a favorably positioned coronal hole. Quiet to unsettled levels are expected on 23 February as the coronal hole wanes.

III. Event Probabilities 21 Feb-23 Feb

Class M 01/01/01

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 20 Feb 076

Predicted 21 Feb-23 Feb 075/075/075

90 Day Mean 20 Feb 085

V. Geomagnetic A Indices

Observed Afr/Ap 19 Feb 005/006

Estimated Afr/Ap 20 Feb 015/020

Predicted Afr/Ap 21 Feb-23 Feb 010/015-012/020-008/015 VI. Geomagnetic Activity Probabilities 21 Feb-23 Feb A. Middle Latitudes

Active 20/25/20

Minor storm 05/10/05

Major-severe storm 01/05/01

B. High Latitudes

Active 30/35/30

Minor storm 15/25/15

Major-severe storm 05/15/05