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Wednesday, September 28, 2011

Weekly Propagation Forecast Bulletins




Product: Weekly Highlights and Forecasts
:Issued: 2011 Sep 27 2159 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 19 - 25 September 2011

Solar activity ranged from low to high levels during the period. Activity was low during 19 - 20 September with C-class flares from Regions 1295 (N22, L = 057, class/area Ekc/550 on 23 September), 1296 (N26, L = 040, class/area Dai/130 on 15 September), and 1301 (N19, L = 330, class/area Eso/210 on 21 September). Activity increased to moderate levels on 21 September due to an M1 x-ray flare at 21/1223Z. A further increase to high levels occurred on 22 September with an X1/2n flare at 22/1101Z from Region 1302 (N12, L = 282, class/area Fkc/1300 on 24 September) as it rotated into view. The X1 was associated with Types II/IV radio sweeps, a Tenflare, and a non-Earth-directed CME. Activity decreased to moderate levels on 23 September with low-level M-class flares from Regions 1295 and 1302. Activity returned to high levels on 24 September with three major flares from Region 1302: an X1/2b at 24/0940Z associated with Types II/IV radio sweeps, a Tenflare, and a halo-CME; an M7/1f at 24/1320Z, with a much faster partial halo CME that appears to overtake the previous CME; and an M5 at 24/2036Z. Finally, an M3 flare from Region 1302 at 24/1921Z had an associated Type II sweep, Tenflare, and partial-halo CME (estimated P.O.S. speed 632 km/s). Activity decreased to high levels on 25 September with Region 1302 and 1303 (S28, L = 034, class/area Cso/070 on 25 September) both producing multiple M-class events.

A greater than 10 MeV proton event at geosynchronous orbit began at 23/2255Z in response to the X1 flare on 22 September and was in progress at the close of the summary period.

The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels during 19 - 21 September. Fluxes decreased to normal levels during 22 - 25 September.

Geomagnetic activity was at quiet levels during most of the period.

Forecast of Solar and Geomagnetic Activity 28 September - 24 October 2011

Solar activity is expected to be at moderate to high levels with more major flare activity from Region 1302 until it crosses the west limb on 03 October. Activity is expected to decrease to low levels during 04 - 19 October.On 20 October, activity is expected to increase to low - moderate levels with the return of Region 1302 for the remainde of the forecast period.

There will be a chance for another proton flare from Region 1302 until it departs the visible disk on 04 October. No proton events are expected at geosynchronous orbit for the remainder of the period.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels during 28 September - 03 October. An increase to normal to high flux levels is expected during 04 - 05 October due to CH HSS effects. Normal to moderate fluxes are expected during 06 - 10 October as CH HSS effects subside. Fluxes are expected to rise to normal to high levels from 11 - 15 October due to CH HSS effects. 1A return to normal to moderate background levels is expected from 16 - 24 October.

Geomagnetic activity is expected to be at unsettled to active levels on 28 September as CME effects subside. A decrease to quiet levels is expected on 29 - 30 September. Activity is expected to increase to quiet to unsettled levels during 01-02 October due to a coronal hole high-speed stream (CH HSS). A return to quiet levels is expected during 02 - 07 October. Activity is expected to increase to quiet to active levels during 08 - 11 October as another CH HSS disturbs the field. A return to predominantly quiet levels is expected for the remainder of the period.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2011 Sep 27 2159 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC webcontact www.swpc.noaa.gov/wwire.html
#
# 27-day Space Weather Outlook Table
# Issued 2011-09-27
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2011 Sep 28 140 15 4
2011 Sep 29 135 5 2
2011 Sep 30 130 5 2
2011 Oct 01 130 8 3
2011 Oct 02 130 5 2
2011 Oct 03 130 5 2
2011 Oct 04 125 5 2
2011 Oct 05 120 5 2
2011 Oct 06 115 5 2
2011 Oct 07 115 5 2
2011 Oct 08 120 8 3
2011 Oct 09 125 15 4
2011 Oct 10 125 12 3
2011 Oct 11 125 8 3
2011 Oct 12 125 5 2
2011 Oct 13 125 5 2
2011 Oct 14 125 5 2
2011 Oct 15 125 5 2
2011 Oct 16 130 5 2
2011 Oct 17 130 5 2
2011 Oct 18 130 5 2
2011 Oct 19 125 5 2
2011 Oct 20 125 5 2
2011 Oct 21 125 5 2
2011 Oct 22 120 8 3
2011 Oct 23 120 5 2
2011 Oct 24 120 8 3
(NOAA)