Product: Weekly Highlights and Forecasts
:Issued: 2012 Sep 24 1239 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 17 - 23 September 2012
Solar activity reached low levels this week. C-class x-ray flares were observed on 17-20 and 23 September. The largest, a C2/Sf, was recorded from Region 1576 (S21, L=180, class/area Dso/70 on 20 September) at 19/1512 UTC. The remainder included a C2 flare from Region 1575 (N08, L=181, class/area Eko/320 on 22 September) at 17/1406 UTC, a C1 at 18/1009Z, and a C1 from Region 1574 (S22, L=302, class/area Cao/40 on 20 September) at 20/1139 UTC, and a long-duration C1 from beyond the east limb at 23/1556 UTC. The long-duration C-flare was associated with a vivid CME in LASCO C2 imagery. Estimated plane-of-sky speed was around 600 km/s.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached moderate levels each day of the week except the 20th when it remained at background levels.
The geomagnetic field ranged from quiet to active levels during the week, with minor storm levels observed at high latitudes on all but the first and last days. The week began with the geomagnetic field at quiet to unsettled levels. Geomagnetic field activity increased to active levels late on the 19th when a corotating interaction region (CIR) became geoeffective. A coronal hole high speed stream
followed on the 20th bringing mostly quiet to unsettled conditions. Between the 19th and the 20th, the solar sector changed from positive to negative, consistent with the geoeffective coronal hole
polarity. Solar wind speed at the ACE spacecraft fluctuated between 600 and 400 km/s between the 20th and 21st, before beginning a slow decline late on the 21st. Solar wind speed by the end of the week had dropped to about 350 km/s. The Bz component of the interplanetary magnetic field reached its maximum of approximately -11 nT late on the 19th with the arrival of the CIR.
Forecast of Solar and Geomagnetic Activity 24 September - 20 October 2012
Solar activity is expected to be at low levels with an increasing chance for moderate activity during the first two weeks of the period as active regions rotate onto the visible disk.
A slight chance for a proton event exists due to potential activity associated with returning regions from 24 September through 08 October.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at high levels on 8-9 October and again on 17-18 October.
Geomagnetic field activity is expected to remain mostly at quiet to unsettled levels except for 3-5 October, 09-10 October, and 16-17 October when recurrent coronal hole high speed streams are expected to bring a chance for active levels.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2012 Sep 24 1239 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 2012-09-24
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2012 Sep 24 135 5 2
2012 Sep 25 140 5 2
2012 Sep 26 145 5 2
2012 Sep 27 145 5 2
2012 Sep 28 150 5 2
2012 Sep 29 150 5 2
2012 Sep 30 145 5 2
2012 Oct 01 140 5 2
2012 Oct 02 135 5 2
2012 Oct 03 130 10 3
2012 Oct 04 130 8 3
2012 Oct 05 130 8 3
2012 Oct 06 125 5 2
2012 Oct 07 125 5 2
2012 Oct 08 120 5 2
2012 Oct 09 115 8 3
2012 Oct 10 115 8 3
2012 Oct 11 120 5 2
2012 Oct 12 115 5 2
2012 Oct 13 115 5 2
2012 Oct 14 120 5 2
2012 Oct 15 120 8 3
2012 Oct 16 130 12 3
2012 Oct 17 140 10 3
2012 Oct 18 140 5 2
2012 Oct 19 145 5 2
2012 Oct 20 150 5 2
(NOAA)
