Product: Weekly Highlights and Forecasts
:Issued: 2012 Mar 19 1253 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 12 - 18 March 2012
Solar activity was at low to high levels during the period. Region 1429 (N17, L = 299, class/area Dkc/1270 on 07 March) produced the largest event of the period, an M7/1b x-ray flare at 13/1741 UTC. Associated with this event, were a 1400 sfu Tenflare, a Type II and a Type IV radio sweep, with an estimated shock velocity of 1366 km/s, and finally an asymmetric full-halo CME, visible in both LASCO C2 and C3 imagery. Plane-of-sky speed, as measured from LASCO imagery was 1375 km/s. The CME associated with this event was forecast to become geoeffective. As Region 1429 approached the west limb, finally rotating off on 16 March, Region 1432 (N14, L = 223, class/area Esi/100 on 15 March) became active and produced two M-class events. The largest was an M2/1n x-ray event at 14/1521 UTC.
A faint CME, visible in LASCO C2 imagery, was observed with a plane-of-sky speed of 392 km/s. On 15 March, a second M-class event, an M1/1f x-ray event at 15/0752 UTC, was also observed. A Type II radio sweep with an estimated shock velocity of 468 km/s was associated with this event. Both CME’s associated with the solar flares from Region 1432 were expected to arrive at Earth, but with such slow speeds and a coronal hole high speed stream (CH HSS)
preceding them, very little effects were forecast. Finally, Region 1434 (S22, L = 205, class/area on 11 March) produced an M1/Sf x-ray event at 17/2039 UTC. Another Type II radio sweep with an estimated shock velocity of 1140 km/s was associated with this event. However,the associated CME with this event was not expected to become geoeffective. Aside from the M-class x-ray events, multiple C-class events were observed during the period. Many of the solar regions remained active as they evolved around the disk, but Region 1435 (S25, L = 220, class/area Dao/150 on 18 March) showed rapid growth towards the end of the summary period.
Two separate greater than 10 MeV proton events were observed during the summary period. The period began with the greater than 10 MeV proton flux above the 10 pfu threshold. This event was associated with the X5/3b x-ray flare observed on 07/0024 UTC. This event began on 07/0510 UTC, reached a maximum flux of 6530 pfu on 08/1115 UTC, and dropped below the 10 pfu threshold at 12/2050 UTC. The second event, began on 13 March and was associated the M7/1b x-ray event, mentioned earlier, from old Region 1429 (N18, L = 299). This greater than 10 MeV proton event began at 13/1810 UTC, reached a maximum flux of 469 pfu on 13/2045 UTC, and dropped below the 10 pfu threshold on 15/0620 UTC. A greater than 100 MeV proton event was also associated with the M7/1b x-ray event. This event began at 13/1810 UTC, reached a maximum flux of 1 pfu at 13/1905 UTC, and dropped below the 1 pfu threshold at 13/2255 UTC.
The greater than 2 MeV electron flux at geosynchronous orbit was at moderate to high levels for the entire summary period.
The geomagnetic field ranged from quiet to major storm periods with isolated severe storm periods observed at high latitudes. The summary period began at quiet levels, however midday on 12 March, a shock was observed by the ACE spacecraft with a Sudden Impulse of 96 nT, later observed by the Boulder magnetometer. This activity was due to the arrival of a CME associated with the 10 March M8 x-ray event from Region 1429. Measurements by the ACE spacecraft showed the solar wind speed increased from around 450 km/s to 775 km/s.
The Interplanetary Magnetic Field (IMF) also increased from around 6 nT to 28 nT. As the effects of the CME continued, periods of major storms were observed with isolated sever storm levels at high latitudes from 12/0900-1500 UTC. From 13-14 March, quiet to active levels were recorded as effects from this CME event waned. On 15 March, another CME arrival was observed with another shock recorded by the ACE spacecraft, followed by a Sudden Impulse of 27 nT measured at the Boulder magnetometer. Solar wind measurements, as recorded by the ACE spacecraft, showed wind speeds around 800 km/s following the shock.
Once again, quiet to major storms were observed at mid latitudes with isolated periods at sever storm levels at high latitudes. For the remainder of the summary period, 16-18 March, solar wind speeds remained elevated, well above 500 km/s, in response to a CH HSS behind the CME arrival on 15 March. The combined effects of the CME and CH HSS produced quiet to active levels at mid latitudes with continued minor to major storm periods observed at high latitudes.
Forecast of Solar and Geomagnetic Activity 19 March - 14 April 2012
Solar activity is expected to remain at low levels from 19 -26 March. On March 27, and then March 28, old Region 1430 (N22, L = 318) and Region 1429 (N18, L = 299) are expected to return, respectively. Even though these regions are on the far side of the solar disk, imagery supports that they are still active and producing CMEs. An increase to low to moderate levels is expected from 28 March - 11 April as both regions populate to front side of the solar disk. A return to predominantly low levels is expected to prevail for the remainder of the forecast period.
No proton events are forecast from 19 - 29 March. An increase to a slight chance for proton events is forecast from 30 March - 11 April as old Region 1429 populates the visible disk. A return to background proton flux levels is expected from 12 April - 14 April.
Electrons, greater than 2 MeV, are expected to be at high levels from 18-25 March. A decrease to normal to moderate levels is expected from 26 - 28 March. From 29 March - 03 April, a return to moderate to high levels is forecast. From 04 April, through the end of the forecast period, 14 April, a return to normal to moderate levels is expected.
The geomagnetic field is expected to be at quiet to active levels on 19-20 March, in response to the arrival and lingering effects of a CME. Predominantly quiet levels are expected to prevail from 21-27 March. On 28 - 31 March, a CH HSS is expected to become geoeffective with quiet to active conditions expected. Quiet conditions are expected from 01 - 02 April. From 03 - 04 April, quiet to unsettled conditions are expected as another CH HSS moves into a geoeffective position. Predominantly quiet levels are expected to continue from 05 - 12 April. From 13-14 April, a CH HSS is expected to become geoeffective.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2012 Mar 19 1253 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 2012-03-19
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2012 Mar 19 100 15 4
2012 Mar 20 105 10 3
2012 Mar 21 105 5 2
2012 Mar 22 100 5 2
2012 Mar 23 100 5 2
2012 Mar 24 100 5 2
2012 Mar 25 100 5 2
2012 Mar 26 100 5 2
2012 Mar 27 105 5 2
2012 Mar 28 115 10 3
2012 Mar 29 120 8 3
2012 Mar 30 130 8 3
2012 Mar 31 130 8 3
2012 Apr 01 130 5 2
2012 Apr 02 130 5 2
2012 Apr 03 135 8 3
2012 Apr 04 135 8 3
2012 Apr 05 135 5 2
2012 Apr 06 135 5 2
2012 Apr 07 130 5 2
2012 Apr 08 120 5 2
2012 Apr 09 115 5 2
2012 Apr 10 105 5 2
2012 Apr 11 100 5 2
2012 Apr 12 100 5 2
2012 Apr 13 100 15 4
2012 Apr 14 100 10 3
(NOAA)
