Joint USAF/NOAA Report of Solar and Geophysical Activity 29 Mar 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Mar 29 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 089 Issued at 2200Z on 29 Mar 2008

IA. Analysis of Solar Active Regions and Activity from 28/2100Z to 29/2100Z: Solar activity was very low. The three spotted regions on the disk, 987 (S06W31), 988 (S08W06), and 989 (S12E23) were all generally stable and quiet during the past 24 hours.

IB. Solar Activity Forecast: Solar activity is expected to be very low. There is a chance, however, for an isolated C-class event during the next three days (30 March – 01 April).

IIA. Geophysical Activity Summary 28/2100Z to 29/2100Z: The geomagnetic field was quiet to unsettled. Solar wind speed as measured at ACE showed a downward trend during the period which is indicative of the decline of the high speed solar wind stream; day-end values were around 550 km/s. The greater than 2 MeV electron flux at geosynchronous orbit reached very high levels during the past 24 hours.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled for the first day (30 March) and is expected to be predominantly quiet for the second and third days (31 March – 01 April).

III. Event Probabilities 30 Mar-01 Apr

• Class M 05/05/05
• Class X 01/01/01
• Proton 01/01/01
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 29 Mar 083
• Predicted 30 Mar-01 Apr 080/080/080
• 90 Day Mean 29 Mar 073

V. Geomagnetic A Indices

• Observed Afr/Ap 28 Mar 013/021
• Estimated Afr/Ap 29 Mar 010/010
• Predicted Afr/Ap 30 Mar-01 Apr 008/010-005/005-005/008

VI. Geomagnetic Activity Probabilities 30 Mar-01 Apr

A. Middle Latitudes

• Active 20/10/10
• Minor storm 10/05/05
• Major-severe storm 05/01/01

B. High Latitudes

• Active 25/15/15
• Minor storm 15/05/05
• Major-severe storm 05/01/01