Product: Weekly Highlights and Forecasts:Issued: 2011 May 17 1420 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
#
Highlights of Solar and Geomagnetic Activity 09 - 15 May 2011
Solar activity was at very low to low levels with isolated B and C-class flares observed. Two CMEs on the earthward side of the sun were observed during the period. The first CME was associated with a C5 x-ray event at 09/2059 UTC from a region rounding the NE limb. It appeared to be the return of old Region 1193 (N17, L=266). This event produced a partial-halo CME with an estimated plane-of-sky velocity of 1225 km/s, based on SOHO/LASCO imagery. The second CME was associated with a B8 x-ray event at 11/0243 UTC, likely associated with a filament eruption between Region 1205 (N14, L=036, class/area Bxo/010 on 03 May) and Region 1207 (N24, L=007, class/area Bxo/020 on 05 May). Associated with the second CME was a Type II radio sweep (632 km/s). Based on SOHO/LASCO imagery, the estimated plane-of-sky velocity was 420 km/s. The rest of the disk was populated with numerous small, magnetically simple spot groups.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit was at high levels on 09 May and at moderate levels 10 - 15 May.
Geomagnetic activity ranged from quiet to active levels during the period. Activity was at quiet levels on 09 May. Levels increased to quiet to unsettled, with isolated active periods on 10 - 11 May. This increase in activity was associated with the onset of a CH HSS. Activity decreased to quiet levels from 12 - 13 May before increasing to unsettled to active conditions midday on 14 May with the onset of another CH HSS. Conditions were mostly quiet to unsettled on 15 May as weak HSS effects continued.
Forecast of Solar and Geomagnetic Activity 18 May - 13 June 2011
Solar activity is expected to be at very low to low levels through the forecast period. There is a slight chance for isolated periods of moderate levels due to the possible emergence of new regions as well as the return of old regions.
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 flux levels during 18 - 20 May, normal to moderate flux levels on 21 - 26 May and back to moderate to high flux levels 27 - 29 May. This forecast is based on anticipated recurrent CH HSS influences.
Geomagnetic activity is expected to be at predominately quiet to unsettled levels on 17 May due to continued recurrent CH HSS effects. Activity is expected to decrease to mostly quiet levels during 18 - 25 May. The field is expected to be under the influence of a recurrent negative polarity CH HSS during 26 - 30 May. During this period, quiet to unsettled levels are expected, with isolated active periods on 27 May. Mostly quiet conditions are forecasted to return 31 May - 5 June, before another CH HSS is expected to return. Mostly quiet to unsettled conditions are expected 6 - 7 June from this small feature, before returning to quiet conditions 8 - 10 June. Mostly unsettled to active conditions are expected to return 11 - 13 June as HSS effects from the CH we are currently under the influence of should return.
Product: 27-day Space Weather Outlook Table
:Issued: 2011 May 17 1420 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 2011-05-17
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2011 May 18 100 5 2
2011 May 19 105 5 2
2011 May 20 110 5 2
2011 May 21 110 5 2
2011 May 22 110 5 2
2011 May 23 110 5 2
2011 May 24 110 5 2
2011 May 25 110 5 2
2011 May 26 110 12 3
2011 May 27 110 22 5
2011 May 28 110 18 5
2011 May 29 110 18 5
2011 May 30 110 15 3
2011 May 31 105 8 3
2011 Jun 01 105 5 2
2011 Jun 02 105 5 2
2011 Jun 03 105 5 2
2011 Jun 04 105 5 2
2011 Jun 05 105 5 2
2011 Jun 06 100 8 3
2011 Jun 07 95 8 3
2011 Jun 08 90 5 2
2011 Jun 09 90 5 2
2011 Jun 10 90 5 2
2011 Jun 11 95 12 4
2011 Jun 12 95 12 4
2011 Jun 13 92 8 3
(NOAA)