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Tuesday, July 17, 2007

Weekly shortwave propagation report


Weekly Highlights and Forecasts
:Issued: 2007 Jul 17 1923 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
09 - 15 July 2007

Solar activity was very low to low. Region 963 (S06, L = 056, class/area Ehi/530 on 10 July) produced C-class flares during 09 - 10 July, the largest of which was a C8/Sf at 10/1240 UTC. Activity dropped to very low levels for the remainder of the period as Region 963 gradually decayed and simplified.

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 at all latitudes until 10/2100 UTC, then increased to unsettled levels as a recurrent high-speed stream commenced. A further increase to quiet to minor storm levels occurred on 11 July with major storm periods observed at high latitudes as the high-speed stream continued. Field activity decreased to quiet to unsettled levels on 12 - 13 July. Field activity increased to quiet to major storm levels on 14 July as another recurrent coronal hole high-speed stream affected the field.

Activity decreased to quiet to active levels on the final day of the period. ACE solar wind data indicated the onset of a recurrent coronal hole high-speed stream late on 10 July. Velocities increased to a peak of 602 km/sec at 11/1743 UTC. Proton densities increased to a peak of 72 p/cc at 10/2341 UTC in advance of the high-speed stream while total IMF intensity peaked at 20 nT at 11/0208 UTC and Bz reached a minimum of -15 nT at 10/2336 UTC. Another recurrent coronal hole high-speed stream was evident in the ACE data as velocities began to increase on 14 July and eventually reached a peak of 631 km/sec at 15/0332 UTC. Proton densities increased to a peak of 17 p/cc at 14/1713 UTC in advance of the high-speed stream while total IMF intensity peaked at 14 nT at 14/1412 UTC and Bz reached a minimum of -12 nT at 14/1755 UTC.

Forecast of Solar and Geomagnetic Activity
18 July - 13 August 2007

Solar activity is expected to be at very low levels.
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
18 July, 22 - 23 July, 03
August, and 12 - 13 August.

Geomagnetic field activity is expected to be at quiet levels during 18 July. An increase to quiet to active conditions is expected during 20 - 21 July due to recurrent coronal hole high-speed stream.

Mostly quiet conditions are expected during 22 - 30 July. Activity is expected to increase to quiet to active levels on 31 July due to a recurrent coronal hole high-speed stream.

Mostly quiet conditions are expected during 01 - 06 August. Activity is expected to increase to quiet to minor storm levels on 07 August due to a recurrent coronal hole high-speed stream. Quiet to unsettled conditions are expected during 08 - 09 August. Activity is expected to increase to unsettled to minor storm levels on 10 August due to a recurrent coronal hole high-speed stream. Quiet to unsettled conditions are expected for the rest of the period.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2007 Jul 17 1923 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 Jul 17
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2007 Jul 18 70 5 2
2007 Jul 19 70 10 3
2007 Jul 20 70 15 4
2007 Jul 21 70 15 4
2007 Jul 22 70 10 3
2007 Jul 23 70 5 2
2007 Jul 24 70 5 2
2007 Jul 25 70 5 2
2007 Jul 26 70 10 3
2007 Jul 27 70 5 2
2007 Jul 28 70 5 2
2007 Jul 29 70 5 2
2007 Jul 30 70 5 2
2007 Jul 31 70 15 4
2007 Aug 01 70 5 2
2007 Aug 02 70 5 2
2007 Aug 03 75 5 2
2007 Aug 04 75 5 2
2007 Aug 05 75 5 2
2007 Aug 06 75 10 3
2007 Aug 07 75 20 5
2007 Aug 08 75 8 3
2007 Aug 09 75 5 2
2007 Aug 10 75 20 5
2007 Aug 11 75 10 3
2007 Aug 12 75 8 3
2007 Aug 13 70 8 3
(NOAA/HF Radio.org)