Joint USAF/NOAA Report of Solar and Geophysical Activity 16 Apr 2006

Product: Report of Solar-Geophysical Activity
Issued: 2006 Apr 16 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 106 Issued at 2200Z on 16 Apr 2006

IA. Analysis of Solar Active Regions and Activity from 15/2100Z to 16/2100Z: Solar activity was very low. Region 871 (S06W33) produced a B1 flare at 16/1829Z.

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

IIA. Geophysical Activity Summary 15/2100Z to 16/2100Z: The geomagnetic field ranged from quiet to active. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled. Isolated active periods are possible early on 17 April.

III. Event Probabilities 17 Apr-19 Apr

• Class M 01/01/01
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 16 Apr 077
• Predicted 17 Apr-19 Apr 075/075/075
• 90 Day Mean 16 Apr 080

V. Geomagnetic A Indices

• Observed Afr/Ap 15 Apr 018/029
• Estimated Afr/Ap 16 Apr 010/015
• Predicted Afr/Ap 17 Apr-19 Apr 008/008-005/008-005/008

VI. Geomagnetic Activity Probabilities 17 Apr-19 Apr

A. Middle Latitudes

• Active 15/10/10
• Minor storm 05/05/05
• Major-severe storm 01/01/01

B. High Latitudes

• Active 20/20/20
• Minor storm 05/05/05
• Major-severe storm 01/01/01