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Wednesday, July 06, 2011

Weekly Propagation Forecast Bulletin


Weekly Highlights and Forecasts
:Issued: 2011 Jul 05 1804 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/weekly.html





Highlights of Solar and Geomagnetic Activity 27 June - 03 July 2011

Solar activity was very low for 27 June to 02 July and increased to low levels for 03 July. Region 1236 (N17, L=167, class/area Ehi/350 on 15 June), which rotated around west limb on 26 June, produced most of the activity on 27-28 June. Regions 1242 (N17, L=056, class/area Dso/90 on 29 June), 1243 (N16, L=351, class/area Cao/80 on 02 July), and 1244 (N16, L=024, class/area Dso/60 on 03 July) dominated activity for 29 June - 02 July with occasional B-class flares. Region 1244 became the dominant flare producing region on 03 July with a C2/Sf at 1244 UTC. The region also produced a long duration B9/Sf at 03/0024 UTC which was associated with type II and type IV radio sweeps as well as a partial halo CME centered over the southwest limb. No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at high levels for 27-30 June but dropped to background levels for 01-03 July.

Geomagnetic field activity was predominantly quiet for 27-30 June. Quiet to active levels were observed on 01 July due to a high speed stream from a coronal hole. Quiet to unsettled levels prevailed for 02-03 July with some isolated active periods at high latitudes as the high speed stream slowly subsided. The high speed stream was weak with peak velocity around 450 km/s; enhanced activity intervals corresponded to somewhat enhanced negative Bz intervals (e.g. around -5 to -7 nT late in the day on 30 June and early in the day on 03 July).

Forecast of Solar and Geomagnetic Activity 06 July - 01 August 2011

Solar activity is expected to be very low to low for most of the outlook interval. There may be an increase in background levels for 10-21 July with the return of old Region 1236 on 10 July which may also increase activity to low levels. There is a chance that new,
rapidly emerging flux regions could increase activity to moderate levels at any time during the outlook period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at background levels initially. An increase to high levels is expected around 20 July and lasting through 26 July in response to a recurrent high speed stream. Background levels are expected to return for 26 July - 01 August.

Geomagnetic field activity is expected to be quiet to unsettled for 6-8 July. Quiet levels are expected for 09-19 July. An increase to unsettled with a chance for active periods is expected for 18-21 July in response to a recurrent high speed stream. Quiet levels are expected to prevail for 24 July - 28 July. Another increase to unsettled levels is expected for 29-30 July due to another recurrent high speed stream, with quiet levels returning for 31 July - 01 August.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2011 Jul 05 1804 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact www.swpc.noaa.gov/wwire.html
#
# 27-day Space Weather Outlook Table
# Issued 2011-07-05
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2011 Jul 06 82 5 2
2011 Jul 07 80 8 3
2011 Jul 08 80 10 3
2011 Jul 09 82 5 2
2011 Jul 10 84 5 2
2011 Jul 11 86 7 2
2011 Jul 12 88 7 2
2011 Jul 13 90 5 2
2011 Jul 14 90 5 2
2011 Jul 15 90 5 2
2011 Jul 16 90 5 2
2011 Jul 17 90 5 2
2011 Jul 18 88 5 2
2011 Jul 19 88 7 2
2011 Jul 20 88 8 3
2011 Jul 21 88 12 3
2011 Jul 22 86 15 3
2011 Jul 23 86 10 3
2011 Jul 24 86 7 2
2011 Jul 25 86 5 2
2011 Jul 26 86 5 2
2011 Jul 27 86 5 2
2011 Jul 28 86 5 2
2011 Jul 29 86 8 3
2011 Jul 30 85 8 3
2011 Jul 31 85 5 2
2011 Aug 01 85 5 2
(NOAA)