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Tuesday, November 27, 2012

Weekly Propagation Bulletins


Product: Weekly Highlights and Forecasts
:Issued: 2012 Nov 26 0613 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 November 2012
Solar activity ranged from very low to moderate levels. The summary period started out at low levels but changed on day two as Region 1618 (N08, L=135, class/area Ekc/450 millionths on 23 November) and Region 1612 (N09, L=228, class/area Hsx/100 millionths on 12 November) both produced M-class x-ray events. Region 1612 produced an M1 solar flare at 20/1241 UTC with multiple discrete radio frequency bursts. Around the same time, h-alpha imagery indicated multiple filament channel eruptions. LASCO C2/C3 imagery supported a partially Earth directed CME. Region 1618 followed this event with an M1/Sn solar flare at 20/1928 UTC. Associated with this flare were several discrete radio frequency bursts. LASCO C2/C3 imagery indicated a CME, however further analysis indicated that this would not be Earth directed. On 21 November, Region 1618 continued to produce M-class solar flares, with an M1/1n solar flare at 21/0656 UTC and an M3 x-ray event at 21/1530 UTC. Both of these events had Type II and Type IV radio sweeps associated with them. Imagery once again supported another Earth directed CME. Later on 21 November, a
large filament erupted off the north-east limb. Location and imagery suggested this CME would not be Earth directed. Activity declined to very low levels on 22 November. Region 1618 remained a magnetically complex region during this time, however simplification in the leader spots was observed. Low levels prevailed throughout the summary period with Region 1618 producing the occasional C-class events. On 23 November, a large filament eruption was observed in
the southwest quadrant of the solar disk. The associated CME was determined to have an Earth directed component. Towards the end of the summary period, Region 1620 (S13, L=92, class/area Hax/090 millionths on 23 November) started to evolve and produce C-class activity. At the end of the period, Region 1620 was magnetically classified as a beta-gamma.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was high levels on 19, 22 and 23 November. The remaining days were at normal to moderate levels.

Geomagnetic field activity was at quiet to active levels. The summary period began at quiet levels with solar wind speed, as measured by the ACE spacecraft, hovering around 400 km/s. On 20
November, an increase in solar wind speed to around 460 km/s was observed, with sustained periods of the negative Bz component of the (Interplanetary Magnetic Field) IMF. This observed change in the solar wind parameters help drive unsettled to active levels late on 20 November and early into 21 November. Predominantly quiet levels prevailed until late on 23 November when solar wind observations indicated the arrival of a CME. At the ACE spacecraft, solar wind speeds increased from 320km/s - 420 km/s with Bt of the IMF  increasing to around 17 nT. As the CME arrived at Earth, an increase to active levels was observed. As CME effects continued on to 24 November, active to quiet levels were observed with isolated minor to major storm periods observed at high latitudes. As CME effects waned, quiet level prevailed from late on 24 November throughout the
rest of the summary period. Initial analysis and data suggested this was the CME from 20 November, however as the CME progressed, data suggested the incoming CMEs might have merged into this one event.

Forecast of Solar and Geomagnetic Activity - 26 November - 22 December 2012
Solar activity is expected to be at low levels with a chance for M-class flares from 26 November - 01 December as Regions 1620 and 1618 evolve and rotate off the visible disk. A decrease to low
levels is forecast from 02 - 04 December. An increase to low levels with a slight chance for M-class flares is expected for the remainder of the period as Regions 1612, 1618, and 1620 return.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels from 26 November - 05 December, 08- 11 December, and 19-22 December. High levels are
expected at all other times due to coronal hole high speed stream activity.

Geomagnetic field activity is expected to be at quiet to active levels. The forecast period is expected to begin at predominantly quiet levels. On 27 - 29 November, an increase to quiet to active levels is expected as the CME from 23 November is expected to become geoeffective. From 30 November through 05 December, quiet to unsettled levels are expected in response to multiple coronal hole
high speed streams. A return to quiet levels is expected from 06-10 December. Another increase to quiet to unsettled levels is expected on 11-15 December due to recurrent coronal hole high speed streams. A return to quiet levels is expected for the remainder of the
period.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2012 Nov 26 0613 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 2012-11-26
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2012 Nov 26     120          11          3
2012 Nov 27     115          15          3
2012 Nov 28     110           8          3
2012 Nov 29     105           8          3
2012 Nov 30     105          10          3
2012 Dec 01     100           8          3
2012 Dec 02     100           5          2
2012 Dec 03     105           8          3
2012 Dec 04     115          10          4
2012 Dec 05     125           8          3
2012 Dec 06     125           5          2
2012 Dec 07     130           5          2
2012 Dec 08     130           5          2
2012 Dec 09     130           5          2
2012 Dec 10     130           5          2
2012 Dec 11     130          10          3
2012 Dec 12     135           8          3
2012 Dec 13     135           5          2
2012 Dec 14     135           8          3
2012 Dec 15     135           8          3
2012 Dec 16     135           8          3
2012 Dec 17     135           5          2
2012 Dec 18     130           5          2
2012 Dec 19     125           5          2
2012 Dec 20     120           5          2
2012 Dec 21     115           5          2
2012 Dec 22     115           5          2
(NOAA)