:Product: Weekly Highlights and Forecasts :Issued: 2001 Mar 13 2112 UT Highlights of Solar and Geomagnetic Activity 05 - 11 March 2001 Solar activity increased to high levels during the period. The week began with activity at low levels as a few small, growing sunspot groups produced low-level C-class subflares. One of these groups, Region 9368 (S25, L = 088, class/area Eai/610 on 08 March), continued to increase in size and magnetic complexity through 10 March. As it grew, it produced two very impulsive major flares: an M5/1b at 08/1118 UTC and an M6/1b at 10/0405 UTC. Both flares had associated Type II radio sweeps and non-Earth-directed CMEs. Activity returned to low levels on 11 March with isolated C-class subflares as Region 9368 began to decay. Data were available from the Advanced Composition Explorer (ACE) spacecraft for most of the period. Recurrent coronal hole effects occurred on 05 March as velocities increased to as high as 600 km/sec and densities decreased. Coronal hole effects gradually subsided on 06 March. No significant disturbances occurred in the solar wind during the rest of the period. No proton events occurred. However, the greater than 10 MeV flux became slightly enhanced following the M6/1b flare on 10 March. The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels. The geomagnetic field was at unsettled to minor storm levels on 05 March due to recurrent coronal hole effects. Quiet to unsettled conditions prevailed the rest of the period. Forecast of Solar and Geomagnetic Activity 14 March - 09 April 2001 Activity is expected to be mostly low during the period with a fair chance for isolated M-class flares. There will also be a slight chance for an isolated major flare. There will be a slight chance for a proton event during the period. The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels during most of the period. The Geomagnetic field is expected to be at quiet to unsettled levels during most of the period, barring an Earth-directed CME. However, active conditions will be possible around 01 April. .