Product: Weekly Highlights and Forecasts
:Issued: 2013 Oct 14 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 07 - 13 October 2013
The week began at low (07 October), then very low (08 October) levels of solar activity. Moderate levels followed on 09 October when Region 1865 (S22, L=145, class/area=Dkc/270 on 13 October) produced an M2 flare (R1 - Minor) at 09/0148 UTC with no corresponding optical flare reported. This event was associated with weak Type II (estimated speed 791 km/s) and Type IV radio sweeps. Region 1865 appeared to have a magnetic delta configuration in the eastern half of its leader spot as it rotated further into view. Gradual spot and penumbral development was noted in Region 1861 (S09, L=170, lass/area=Dhi/400 on 13 October) with flare-bright plage observed in the northern portion of the regions plage field.
By 11 October, both Regions 1861 and 1865 had grown and developed beta-gamma-delta magnetic configurations. Neither of these regions were responsible for the M1 flare at 11/0725 UTC, however. This
flare originated from a region that was just beginning to rotate onto the NE limb. The event was associated with a Type II sweep (estimated speed 510 km/s), Type IV sweep, and a 380 sfu radio burst at 2695 MHz. The subsequent coronal mass ejection (CME), observed in SOHO/LASCO C2 imagery beginning at 11/0724 UTC was determined by WSA-ENLIL modeling to be mostly directed off the East limb with no
geoeffective component. Another CME was observed off the SE limb in SOHO/LASCO C2 imagery beginning at 11/1400 UTC. This event was associated with a C6 flare that occurred at 11/1228 UTC from Region 1865 and was expected to imact Earth later early on the 15th. Regions 1861 and 1865 remained the largest and most magnetically complex regions on the solar disk in the days that followed.
After a brief respite, solar activity again reached moderate levels when Region 1865 produced an isolated M1/Sf flare (R1-Minor) at 13/0043 UTC which was accompanied by a Type II radio emission at
11/0035 UTC (estimated speed 798 km/s). WSA ENLIL modeling of the associated partial halo coronal mass ejection (CME) suggested an arrival time late on Oct 16. Slight decay was observed in the
intermediate area of Region 1865, however it maintains an East/West oriented inversion line running through its leader spot. Umbral consolidation in the trailing spot and slight decay in intermediate spot area was observed in Region 1861.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels on 12 October at 1520 UTC. For the remainder of the week the flux was at low to moderate levels.
Geomagnetic field activity reached minor storm levels during the week. The period began with a weak CME passage at approximately 07/0035 UTC with minor increases in IMF Bt, speed, and density; associated with the CME observed on Oct. 3. Solar wind speed remained low in the 269 to 341 km/s range. IMF Bt ranged from 4 to 7 nT. IMF Bz was weakly southward during most of the period with a range of 3 to -6 nT. IMF Phi data indicated a positive-polarity (Away) solar sector during the period. The geomagnetic field
responded with quiet to unsettled levels of activity. The following day ACE data indicated an interplanetary shock arrival at approximately 08/1337 UTC with significant increases in wind speed (approximately 300 to 480 km/s), IMF Bt (7 to 35 nT), density, and temperature. The geomagnetic field was at quiet levels until around 08/2023 UTC, then rapidly increased to minor storm levels (G1 - Minor) by 08/2024 UTC. The activity increased following a geomagnetic sudden impulse (SI) at 08/1941 UTC (62 nT, Boulder USGS
magnetometer).
By 09 October, solar wind speed increased to a high of 683 km/s at 09/0311 UTC following the shock arrival, then gradually decreased to a low of 445 km/s at 09/2316 UTC. IMF Bt was elevated through the
period with a peak of 14 nT observed at 09/0900 UTC. IMF Bz was weakly southward during the first half of the period, then became weakly northward during the rest of the day with a range of 7 to -5 nT. Phi data indicated a positive-polarity solar sector during the period. The geomagnetic field was at active to minor storm levels (G1 - Minor) during the first half of the period, then decreased to unsettled levels after 09/1200 UTC. The following day, an isolated active period was observed during 10/0000-0300 UTC as the effects of the CME diminished. Quiet conditons returned on the 11th and remained through the end of the week.
Forecast of Solar and Geomagnetic Activity 14 October - 09 November 2013
Solar activity is expected to be at low levels with a chance for isolated moderate level events through the forecast period.
There is a slight chance of proton events at geosynchronous orbit during the first week of the forecast period as Regions 1861 and 1865 move into more favorable positions in the western hemisphere.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels until 20 October in response to recurrent coronal hole high speed streams. The remainder of the period is expected to see moderate to low flux levels.
Geomagnetic field activity is expected to be at unsettled to active levels on 15-17 October with a slight chance for minor storm periods. This elevated activity is expected in response to coronal mass ejections that occurred on 11 and 13 October coupled with the effects from a positive polarity coronal hole high speed stream. Unsettled to active levels are also expected on 24 October in response to a coronal hole high speed stream. The remainder of the forecast period should be mostly quiet in the absence of any more transient solar wind features.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2013 Oct 14 0630 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 2013-10-14
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2013 Oct 14 125 5 2
2013 Oct 15 125 12 4
2013 Oct 16 125 10 3
2013 Oct 17 120 15 4
2013 Oct 18 120 5 2
2013 Oct 19 115 5 2
2013 Oct 20 110 5 2
2013 Oct 21 105 10 4
2013 Oct 22 105 5 2
2013 Oct 23 105 5 2
2013 Oct 24 100 5 2
2013 Oct 25 100 5 2
2013 Oct 26 100 5 2
2013 Oct 27 100 5 2
2013 Oct 28 100 5 2
2013 Oct 29 100 5 2
2013 Oct 30 105 5 2
2013 Oct 31 105 5 2
2013 Nov 01 100 5 2
2013 Nov 02 100 5 2
2013 Nov 03 110 5 2
2013 Nov 04 110 5 2
2013 Nov 05 115 5 2
2013 Nov 06 120 5 2
2013 Nov 07 120 5 2
2013 Nov 08 125 5 2
2013 Nov 09 125 5 2
(NOAA)