Joint USAF/NOAA Report of Solar and Geophysical Activity 18 Mar 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Mar 18 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 077 Issued at 2200Z on 18 Mar 2007

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity was very low. No flares were observed during the past 24 hours. The visible solar disk remains spotless.

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

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field was quiet to unsettled. Solar wind speed varied during the past 24 hours, from initial values around 520 km/s, to values around 430 km/s at approximately 1540Z, to values around 460 km/s at forecast issue time. The greater than 2 MeV electron flux at geosynchronous orbit remained at high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next three days (19-21 March).

III. Event Probabilities 19 Mar-21 Mar

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

IV. Penticton 10.7 cm Flux

• Observed 18 Mar 071
• Predicted 19 Mar-21 Mar 070/070/070
• 90 Day Mean 18 Mar 078

V. Geomagnetic A Indices

• Observed Afr/Ap 17 Mar 008/008
• Estimated Afr/Ap 18 Mar 003/005
• Predicted Afr/Ap 19 Mar-21 Mar 005/005-005/005-005/005

VI. Geomagnetic Activity Probabilities 19 Mar-21 Mar

A. Middle Latitudes

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

B. High Latitudes

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