Joint USAF/NOAA Report of Solar and Geophysical Activity 10 Apr 2009

Product: Report of Solar-Geophysical Activity
Issued: 2009 Apr 10 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 100 Issued at 2200Z on 10 Apr 2009

IA. Analysis of Solar Active Regions and Activity from 09/2100Z to 10/2100Z: Solar activity was very low. No flares occurred during the past 24 hours. The solar disk continues to void of sunspots.

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

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z: The geomagnetic field was quiet to unsettled during the past 24 hours. Solar wind velocity continued to increase but appears to be leveling out at this time in the range between 500-540 km/s. The interplanetary magnetic field Bz component fluctuated between +/- 4 nT. The signatures in the solar wind continue to be consistent with a high speed stream from a coronal hole.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next three days.

III. Event Probabilities 11 Apr-13 Apr

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

IV. Penticton 10.7 cm Flux

• Observed 10 Apr 069
• Predicted 11 Apr-13 Apr 070/070/070
• 90 Day Mean 10 Apr 070

V. Geomagnetic A Indices

• Observed Afr/Ap 09 Apr 009/012
• Estimated Afr/Ap 10 Apr 007/007
• Predicted Afr/Ap 11 Apr-13 Apr 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 11 Apr-13 Apr

A. Middle Latitudes

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

B. High Latitudes

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