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:Product: Weekly Highlights and Forecasts
:Issued: 2012 Nov 19 0648 UTC # Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center # Product description and SWPC contact on the Web # http://www.swpc.noaa.gov/weekly.html # # Weekly Highlights and Forecasts # Highlights of Solar and Geomagnetic Activity 12 - 18 November 2012 Solar activity ranged from low to high. On 12 November, moderate levels were observed due to a M2 X-ray flare from Region 1613 (S22, L=210, class/area Dso/170 on 12 November) and associated Type II radio sweep (645 km/s) at 12/2328 UTC. Solar activity increased to high levels on 13 November due to a M6 X-ray flare, also from Region 1613, and associated Type II radio sweep (1193 km/s) at 13/0204 UTC. This region also produced two M2 X-ray flares and an associated 10 cm burst of 220 sfu at 13/2052 UTC, but showed signs it was decreasing in areal coverage. Region 1613 continued its M-class flare activity into 14 November, producing a M1 X-ray flare, but continued to slowly decrease in area. A return to low levels was observed from 15 to 18 November. A C8 flare from Region 1618 (N08, L=136, class/area Eai/90 on 18 November) occurred at 16/1539 UTC with an associated Type II radio sweep (511 km/s) and a non-earth directed coronal mass ejections (CME). A long duration C1 flare from Region 1613 also occurred on 16 November with an associated 24 degree filament eruption centered near S39E22. Another filament eruption was observed from the East limb, as seen in SDO/AIA 304 imagery, but analysis of SOHO/LASCO C2 suggested these eruptions would not be geoeffective. While there were many new CMEs observed over the 7 day period, none were determined to be earth-directed and have had little to no observable impacts. No greater than 10 MeV proton events were observed at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit was at normal background levels on 12 and 13 November, but reached moderate levels on 14, 15, and 16 November. The week ended with high levels for 17 and 18 November with the maximum value reaching 3160 pfu. Geomagnetic field activity ranged from quiet to major storm levels. The week started off at quiet to unsettled levels, but by late 12 November to early 13 November, the effects from the two CMEs from 09 and 10 November were being felt. ACE data indicated a shock arrival at 12/2216 UTC and a sudden impulse was observed on earth at 12/2316 UTC (16 nT, as measured by the Boulder USGS magnetometer). The maximum southward component of Bz reached -19.5 nT at 12/2338 UTC, the total IMF reached 22.8 nT at 13/0053 UTC. The solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 504 km/s at 13/0111 UTC. The geomagnetic field responded with unsettled to active levels throughout the day on 13 November, but increased to major storm levels early on 14 November. The increase in activity was caused by prolonged period of negative Bz attributed to a combination of lingering CME effects and a solar sector boundary crossing that occurred at approximately 14/0245 UTC, followed by a negative polarity coronal hole high speed stream (CH HSS). Activity returned to quiet to unsettled levels for the remainder of the week (15 - 18 November). Forecast of Solar and Geomagnetic Activity 19 November - 15 December 2012 Solar activity is expected to be low with a chance for M-class flares through 27 November when Region 1618 is due to rotate off the west limb. Very low to low conditions are expected from 28 November through 05 December. From 06 December to the end of the period, low conditions are expected with a chance for M-class activity with the return of Region 1613. No greater than 10 MeV proton events are expected at geosynchronous orbit. The greater than 2 MeV electron flux at geosynchronous orbit is expected to remain at moderate to high levels through 24 November. Normal levels are expected to return from 25 November through 03 December. Moderate to high levels are expected from 04-06 December due to coronal hole high speed stream (CH HSS) activity. Normal levels are again expected to return from 07 December through 13 December. From 14 December to the end of the period, expect moderate to high levels to return with CH HSS activity once again. Geomagnetic field activity is expected to be mostly quiet through 02 December. Unsettled levels are likely on 03 and 04 December due to a possible solar sector boundary crossing (SSBC) followed by a CH HSS. Mostly quiet levels return from 05 December through the end of the period, except for a chance for unsettled activity on 11 December due to a possible SSBC/CH HSS. |
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