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Monday, October 21, 2013

Weekly Propagation Forecast Bulletins


Product: Weekly Highlights and Forecasts
:Issued: 2013 Oct 21 0329 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 14 - 20 October 2013

Solar activity ranged from low to moderate levels. Low levels were observed on 14 Oct with C-class activity from Regions 1861 (S10, L=168, class/area Dho/480 on 15 Oct), 1865 (S22, L=145, class/area Dkc/270 on 13 Oct) and 1869 (N19, L=085, class/area Dso/040 on 13 Oct). The largest event of the day was a C8/1f at 14/1315 UTC from Region 1865. 15 Oct saw activity increase to moderate levels with a pair of M-class flares from Region 1865, the largest an M1/Sn at 15/0838 UTC. Numerous C-class activity was also seen from Regions 1861 and 1865. No Earth-directed CMEs were observed with the 15 Oct activity. Activity levels dipped to low levels on 16 Oct with Region 1865 producing the largest event of the day, a C8/1n at 16/1432 UTC with an associated asymmetric, partial halo coronal mass ejection (CME). Analysis determined that the relative slow speed (386 km/s) of this CME was unlikely to produce significant effects at Earth.
Region 1861 produced a C1/Sf event at 16/0920 UTC with associated Type II (548 km/s) and Type IV radio sweeps. C-class activity was also observed from Regions 1867 (N24, L=183, class/area Dao/050 on 13 Oct) and 1870 (S13, L=143 class/area Cro/030 on 14 Oct). Activity increased to moderate levels on 17 Oct with Region 1861 producing an M1 flare at 17/1541 UTC. Additional C-class flaring was observed from Regions 1861 and 1865. Activity levels decreased to low on 18 - 20 Oct with C-class events observed from Regions 1861, 1868 (N23, L=102, class/area Cao/040 on 19 Oct) and Region 1975 (N08, L=026, class/area Esi/150 on 19 Oct). 

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at moderate flux levels on 14 - 15 Oct and at high levels 16 - 20 October. 

Geomagnetic field activity ranged from quiet to active levels. The period began with quiet levels, but field activity ramped up to unsettled to active with the onset of a recurrent coronal hole high speed stream (CH HSS). The field remained elevated through early on 16 Oct when predominately quiet levels persisted through the remainder of the summary period. ACE wind signatures indicated an increase in wind speeds from 320 km/s at the beginning of the period to a peak of about 575 km/s at 15/2036 UTC. Corresponding increases in temperature and density accompanied the speed increase. The interplanetary magnetic field (IMF) total field (Bt) reached a peak of 12 nT at 14/0856 UTC with the Bz component reaching a maximum southward extent of -10 nT at 14/0854 UTC. The phi angle switched from a negative (towards) to a positive (away) orientation at 14/0835 UTC and remained predominately positive through the remainder of the summary period. By late on 15 Oct, Bt and Bz closed up with Bz not varying much beyond +/- 3 nT through the balance of the period. Wind speeds slowly decreased to end-of summary period values of just under 300 km/s. 

Forecast of Solar and Geomagnetic Activity 21 October - 16 November 2013

Solar activity is expected to be at low levels with a chance for isolated moderate level events 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 moderate to high levels on 21 Oct, normal to moderate levels on 22 Oct - 10 Nov and moderate to high levels on 11 - 16 Nov. 

Geomagnetic field activity is expected to be at quiet to unsettled levels on 21 - 22 Oct and unsettled to active levels on 10 - 13 Nov due to recurrent CH HSS effects. Predominately quiet levels are expected for the remainder of the outlook period. 

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2013 Oct 21 0329 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact www.swpc.noaa.gov/wwire.html
#
#      27-day Space Weather Outlook Table
#                Issued 2013-10-21
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2013 Oct 21     130          10          3
2013 Oct 22     125           8          3
2013 Oct 23     120           5          2
2013 Oct 24     120           5          2
2013 Oct 25     115           5          2
2013 Oct 26     115           5          2
2013 Oct 27     110           5          2
2013 Oct 28     110           5          2
2013 Oct 29     105           5          2
2013 Oct 30     100           5          2
2013 Oct 31     100           5          2
2013 Nov 01     105           5          2
2013 Nov 02     115           5          2
2013 Nov 03     120           5          2
2013 Nov 04     120           5          2
2013 Nov 05     120           5          2
2013 Nov 06     125           5          2
2013 Nov 07     125           5          2
2013 Nov 08     125           5          2
2013 Nov 09     125           5          2
2013 Nov 10     125          12          4
2013 Nov 11     130          15          4
2013 Nov 12     135          10          3
2013 Nov 13     135           8          3
2013 Nov 14     130           5          2
2013 Nov 15     120           5          2
2013 Nov 16     115           5          2
(NOAA)