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Wednesday, September 26, 2007

Weekly Propagation Forecast Update


Product: Weekly Highlights and Forecasts
:Issued: 2007 Sep 25 1854 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Environment Center
# Product description and SEC contact on the Web
# http://www.sec.noaa.gov/weekly.html
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
17 - 23 September 2007

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 was at normal levels.

The geomagnetic field was quiet during 17 - 19 September. Activity increased to quiet to active levels during the rest of the period. ACE real-time solar wind measurements indicated the increased activity was due to a recurrent coronal hole high-speed wind stream. The high-speed stream commenced around 20/0900 UTC. Velocities gradually increased to a peak of 728 m/sec at 23/0836 UTC, then gradually declined during the rest of the summary period. IMF changes associated with the onset of the high-speed stream included a solar sector boundary crossing (Away (+) to Toward (-)) at around 20/1400 UTC, a peak total field intensity of 13.1 nT at 20/1336 UTC, and a minimum southward Bz reading of -9.1 nT at 20/1330 UTC. The proton density increase associated with the onset of the high-speed stream reached a peak of 20.4 p/cc at 20/2002 UTC.

Forecast of Solar and Geomagnetic Activity
26 September - 22 October 2007

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 26 September - 10 October and 21 - 22 October.

Geomagnetic activity is expected to be at quiet to unsettled levels during 26 - 27 September. Activity is expected to increase to unsettled to minor storm levels during 28 - 30 September due to a recurrent coronal hole high-speed stream. Activity is expected to decrease to quiet to unsettled levels during 01 - 02 October.
Activity is expected to increase to unsettled to active levels during 03 - 04 October due to another recurrent coronal hole high-speed stream. Quiet conditions are expected during 05 - 16 October. An increase to quiet to unsettled levels is expected during 17 - 19 October. A further increase to unsettled to active levels is forecast for 20 October as another recurrent coronal hole high-speed stream affects the field. Activity is expected to decrease to quiet to unsettled levels during the remainder of the period as the high-speed stream subsides.

27-day Space Weather Outlook Table 27DO.txt
:Issued: 2007 Sep 25 1854 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Environment Center
# Product description and SEC contact on the Web
# http://www.sec.noaa.gov/wwire.html
#
# 27-day Space Weather Outlook Table
# Issued 2007 Sep 25
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2007 Sep 26 66 5 2
2007 Sep 27 67 8 3
2007 Sep 28 67 15 4
2007 Sep 29 67 25 5
2007 Sep 30 67 12 3
2007 Oct 01 67 5 2
2007 Oct 02 67 8 3
2007 Oct 03 68 15 4
2007 Oct 04 68 10 3
2007 Oct 05 68 5 2
2007 Oct 06 68 5 2
2007 Oct 07 68 5 2
2007 Oct 08 68 5 2
2007 Oct 09 67 5 2
2007 Oct 10 67 5 2
2007 Oct 11 67 5 2
2007 Oct 12 67 5 2
2007 Oct 13 67 5 2
2007 Oct 14 67 5 2
2007 Oct 15 67 5 2
2007 Oct 16 67 5 2
2007 Oct 17 67 10 3
2007 Oct 18 67 10 3
2007 Oct 19 67 10 3
2007 Oct 20 67 15 4
2007 Oct 21 67 10 3
2007 Oct 22 67 8 3
(NOAA)