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Tuesday, August 28, 2012

Propagation Forecast Bulletins


Product: Weekly Highlights and Forecasts
:Issued: 2012 Aug 27 0630 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
#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 20 - 26 August 2012

Solar activity was very low until 25 and 26 August. The largest flare of the reporting period was a C1/Sf at 25/0236 UTC from Region 1554 (N16, L=215, class/area Dsi/170 on 25 August). No coronal mass ejections observed during the reporting period were Earth-directed.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at high levels from 21 - 24 August. Moderate levels were observed 20 August and again from 25 - 26 August.

Geomagnetic field activity was mostly quiet to unsettled with an isolated active period mid-day on 26 August. At the beginning of the period, solar wind speed, measured at the ACE spacecraft, indicated the presence of a coronal hole high speed stream (CH HSS). Solar wind decreased steadily from approximately 600 km/s to 400 km/s by early on 22 August. Quiet to unsettled conditions were observed on 20 - 21 August. By mid-day on 24 August, the phi angle changed from a positive to negative orientation indicating a solar sector boundary crossing. Solar wind speed began to increase early on 25 August from approximately 400 km/s to 610 km/s as another CH HSS moved into geoeffective position. Solar wind speed increased once
more mid-day on 26 August and ended the period around 700 km/s. Conditions were quiet on 22 August. Conditions remained at quiet to unsettled levels from 23 August until mid-day on 26 August as an isolated active period was observed.

Forecast of Solar and Geomagnetic Activity 27 August - 22 September 2012

Solar activity is expected to be at very low to low levels with a slight chance for M-class activity through the forecast period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at high levels on 29 - 30 August, 09 - 10 September, 16 - 17 September, and again on 22 September due to effects from coronal hole high speed streams.

Geomagnetic field activity is expected to be mostly quiet to unsettled until 15 September as a recurrent coronal hole high speed stream moves into a geoeffective position. Unsettled to active conditions are expected on 15 - 16 September. Conditions are expected to be mostly quiet to unsettled again from 17 September through 21 September. Another recurrent coronal hole high speed stream is expected to become geoeffective on 22 September causing unsettled to active conditions.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2012 Aug 27 0630 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPCweb contact www.swpc.noaa.gov/wwire.html
#
# 27-day Space Weather Outlook Table
# Issued 2012-08-27
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2012 Aug 27 115 8 3
2012 Aug 28 120 8 3
2012 Aug 29 120 8 3
2012 Aug 30 125 5 2
2012 Aug 31 125 5 2
2012 Sep 01 125 5 2
2012 Sep 02 120 5 2
2012 Sep 03 120 5 2
2012 Sep 04 120 5 2
2012 Sep 05 120 5 2
2012 Sep 06 115 5 2
2012 Sep 07 115 5 2
2012 Sep 08 115 8 3
2012 Sep 09 110 8 3
2012 Sep 10 110 5 2
2012 Sep 11 105 5 2
2012 Sep 12 105 5 2
2012 Sep 13 100 5 2
2012 Sep 14 100 5 2
2012 Sep 15 100 12 4
2012 Sep 16 100 12 4
2012 Sep 17 95 8 3
2012 Sep 18 95 8 3
2012 Sep 19 95 5 2
2012 Sep 20 95 8 3
2012 Sep 21 95 8 3
2012 Sep 22 95 10 4
(NOAA)