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Monday, April 08, 2013

Weekly Propagation Forecast Bulletins




Product: Weekly Highlights and Forecasts
:Issued: 2013 Apr 08 0354 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 01 - 07 April 2013

Solar activity began the period at very low levels on 01-02 April. By 03 April, solar activity increased to low levels and continued at low levels through 04 April due to several low level C-class flares from Regions 1708 (N11, L=190, class/area Dao/090 on 29 March), 1711 (S19, L=158, class/area Cko/580 on 04 April), and 1713 (N10, L=175, class/area Dai/130 on 06 April). By 05 April, solar activity reached moderate levels with an isolated M2 flare at 05/1748 UTC from Region 1719 (N08, L=076, class/area Dsi/150 on 07 April. Earlier on 05 April, a long duration C2 flare was observed at 05/0650 UTC, also from Region 1719 as it began to rotate onto the east limb. An associated coronal mass ejection (CME) was observed off the east limb in SOHO/LASCO C2 imagery beginning at 05/0712 UTC, but was not Earth-directed. By 06-07 April, solar activity returned to low levels with the majority of the C-class flares from Regions 1718 (N20, L=109, class/area Dai/140 on 07 April) and 1719. No Earth-directed CMEs were observed during the reporting period. 

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
high levels on 01-05 April and decreased to moderate levels by 06-07
April. The maximum weekly flux value of 5166 pfu was observed at
02/1735 UTC. 

Geomagnetic field activity was at quiet levels with isolated active periods at high latitudes mid-day on 01 and 07 April. Solar wind speed began the period decreasing from approximately 480 km/s to a low near 250 km/s by late on 05 April while the total field strength slowly increased from 2 nT to 6 nT. By Early on 06 April, solar wind speed started to increase to 340-370 km/s while total field strength increased to 5-7 nT. Solar wind speed was relatively constant near
the 330-350 km/s range through the end of the reporting period. Phi angle was mostly negative (towards) through approximately 07/1500 UTC when a change to a more positive (away) sector occurred. 

Forecast of Solar and Geomagnetic Activity 08 April - 04 May 2013

Solar activity is expected to be at very low to low levels with a chance for M-class flaring from 08-19 April as Regions 1713, 1718, and 1719 continue to transit across the visible disk. From 20 April until the end of the forecast period, very low to low levels are expected. 

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels with a chance for high levels on 24 April-02 May due to recurrent coronal hole high speed stream (CH HSS) effects. 

Geomagnetic field activity is expected to be quiet to unsettled on 08-09 April due to weak CH HSS effects. Mostly quiet conditions will prevail until another CH HSS moves into geoeffective position on 23 April. Quiet to unsettle conditions with a chance for isolated active periods are expected on 23 April with quiet to unsettled levels on 24 April. Another CH HSS is expected to become geoeffective on 25-26 April causing unsettled to active conditions with minor storm periods possible. Conditions are expected to return to mostly quiet levels by 27 April through the end of the forecast period. 



Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2013 Apr 08 0354 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 2013-04-08
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2013 Apr 08     138           8          3
2013 Apr 09     135           8          3
2013 Apr 10     130           5          2
2013 Apr 11     120           5          2
2013 Apr 12     115           5          2
2013 Apr 13     115           5          2
2013 Apr 14     110           5          2
2013 Apr 15     105           5          2
2013 Apr 16     105           5          2
2013 Apr 17     105           5          2
2013 Apr 18     100           5          2
2013 Apr 19     100           5          2
2013 Apr 20      95           5          2
2013 Apr 21      95           5          2
2013 Apr 22      95           5          2
2013 Apr 23      95          12          3
2013 Apr 24     100           8          3
2013 Apr 25     105          18          4
2013 Apr 26     110          15          4
2013 Apr 27     115           5          2
2013 Apr 28     120           5          2
2013 Apr 29     125           5          2
2013 Apr 30     125           5          2
2013 May 01     125           5          2
2013 May 02     130           5          2
2013 May 03     130           5          2
2013 May 04     130           5          2
(NOAA)