Report of Solar-Geophysical Activity

Issued: 2006 Mar 19 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 078 Issued at 2200Z on 19 Mar 2006 IA. Analysis of Solar Active Regions and Activity from 18/2100Z to 19/2100Z: Solar activity continues at very low levels. No significant activity was observed during the period. No new regions were numbered today.

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

IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z:

The geomagnetic field was at quiet to major storm levels. The elevated activity is due to a recurrent high speed coronal hole stream. Early in the period, the solar wind speeds increased from 550 km/sec to over 650 km/sec. The Bz component of the interplanetary magnetic field remained predominantly southward for several hours prior to the occurrence of the major storm conditions.

The greater than 2 MeV electron flux at geosynchronous orbit reached high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from quiet to active levels on 20 March due to continued coronal hole effects. Predominantly unsettled conditions are expected on 21 March as the coronal hole wanes. Quiet levels are expected on 22 March.

III. Event Probabilities 20 Mar-22 Mar

Class M 01/01/01

Class X 01/01/01

Proton 01/01/01

PCAF green

IV. Penticton 10.7 cm Flux

Observed 19 Mar 075

Predicted 20 Mar-22 Mar 075/075/075

90 Day Mean 19 Mar 080

V. Geomagnetic A Indices

Observed Afr/Ap 18 Mar 015/026

Estimated Afr/Ap 19 Mar 026/040

Predicted Afr/Ap 20 Mar-22 Mar 012/020-010/012-005/008 VI. Geomagnetic Activity Probabilities 20 Mar-22 Mar A. Middle Latitudes

Active 25/20/15

Minor storm 10/05/01

Major-severe storm 05/01/01

B. High Latitudes

Active 45/30/20

Minor storm 20/10/05

Major-severe storm 15/05/01