:Product: Weekly Highlights and Forecasts
:Issued: 2008 Aug 26 2251 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/weekly.html
#
#                Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
18 - 24 August 2008

Solar activity was very low. No flares were detected. The visible
disk was spotless.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels during 19 - 24 August.

Geomagnetic field activity ranged from unsettled to minor storm
levels on 18 August with major to severe storm periods observed at
high latitudes. Activity decreased to predominantly quiet to
unsettled levels during 19 - 21 August, though active to major storm
periods were observed at high latitudes on 19 August. Activity
decreased to quiet levels during 22 - 24 August. ACE solar wind data
indicated a recurrent coronal hole high-speed stream commenced on 18
August. Velocities increased to a maximum of 660 km/sec at 18/1353
UTC, then gradually decreased during the rest of the period with a
minimum of 297 km/sec at 24/2309 UTC. Interplanetary magnetic field
changes associated with the onset of the high-speed stream included
increased Bt (maximum 12 nT at 18/1040 UTC) and intermittent periods
of southward Bz (minimum -10 nT at 18/1013 UTC).

Forecast of Solar and Geomagnetic Activity
27 August - 22 September 2008

Solar activity is expected to be very low.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to reach high levels during 07 - 12 September and 15 - 22
September.

Geomagnetic field activity is expected to be at quiet levels during
27 August - 04 September. Activity is expected to increase to active
levels on 05 September due to a recurrent coronal hole high-speed
stream. Activity is expected to decrease to quiet to unsettled
levels during 06 - 07 September as the high-speed stream subsides.
Quiet conditions are expected during 08 - 11 September. Activity is
expected to increase to unsettled levels during 12 - 13 September. 
Activity is expected to increase to active to minor storm levels on
14 September due to a recurrent coronal hole high-speed stream.
Activity is expected to decrease to unsettled levels during 15 - 16
September as the high-speed stream subsides. Quiet conditions are
expected during 17 - 22 September.