Product: Weekly Highlights and Forecasts:Issued: 2008 May 01 1609 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
21 - 27 April 2008
Solar activity was very low. Region 992 (N13W17, L= 275, class/area, Cso/040 on 23 April) formed on the disk on 22 April, but decayed to a spotless plage region by 25 April. On 26 April, a B3/Sf flare was observed at 1408 UTC from an unnumbered area of spotless plage near
N08E09. The flare was associated with a wave that was visible in EUV imagery on STEREO and SOHO, a Type II radio sweep (estimated shock velocity of 608 km/s), as well as a slow, faint, asymmetrical, full-halo CME visible in coronagraph imagery. The estimated plane-of-sky speed for the CME was around 430-480 km/s.
No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during 24 - 27 April.
Geomagnetic field activity was at mostly quiet levels during 21 - 22 April. Activity increased to unsettled to active levels early on 23 April with minor to major storm periods detected at high latitudes.
These levels persisted through midday on 24 April. Thereafter, and through the remainder of the summary period, activity decreased to mostly quiet levels at middle latitudes, while high latitudes experienced mostly unsettled to active levels with some isolated minor storm periods. ACE solar wind measurements indicated a solar sector boundary (SSB) crossing from ‘away’ orientation (positive) to ‘towards’ orientation (negative) at about 22/1410 UTC. Increases in
solar wind velocity, density, and temperature, along with positive and negative fluctuations in IMF Bz followed the SSB. These signatures were consistent with a co-rotating interaction region
(CIR) followed by a high speed solar wind stream. Interplanetary magnetic field changes during the CIR included increased Bt (peak 14 nT at 23/0708 UTC) and increased Bz variability (minimum -13 nT at 23/0710 UTC and maximum +10 nT at 23/0919 UTC). The high speed
stream commenced during the later half of 23 April. ACE detected a peak velocity of 695 km/s at 23/1849 UTC and a density maximum of 20 p/cc at 23/0413 UTC. Velocities decreased during 17 April, but remained elevated during the remainder of the period (range: 450 -
525 km/sec).
Forecast of Solar and Geomagnetic Activity
30 April - 26 May 2008
Solar activity is expected to be very low.
No proton events are expected at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels during
30 April - 12 May and 21 - 26
May.
Geomagnetic field activity is expected to be at unsettled to active levels during 30 April - 07 May with minor storm levels possible on 01 May as a recurrent coronal hole high-speed stream affects the field. Activity is expected to decrease to quiet to unsettled levels during 08 - 18 May as the high-speed stream subsides. Activity is expected to increase to unsettled to active levels on 19 - 21 May with minor storm periods possible on 20 May as another recurrent coronal hole high-speed stream affects the field. Quiet to unsettled levels will return on 22 - 26 May.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2008 May 01 1609 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/wwire.html
# 27-day Space Weather Outlook Table# Issued 2008 Apr 29
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2008 Apr 30 70 12 4
2008 May 01 70 15 5
2008 May 02 70 10 3
2008 May 03 70 10 3
2008 May 04 70 10 3
2008 May 05 70 8 3
2008 May 06 70 10 3
2008 May 07 70 10 3
2008 May 08 70 5 2
2008 May 09 70 5 2
2008 May 10 70 5 2
2008 May 11 70 5 2
2008 May 12 70 5 2
2008 May 13 70 8 3
2008 May 14 70 5 2
2008 May 15 70 5 2
2008 May 16 70 5 2
2008 May 17 70 5 2
2008 May 18 70 5 2
2008 May 19 70 10 3
2008 May 20 70 15 5
2008 May 21 70 12 4
2008 May 22 70 8 3
2008 May 23 70 5 2
2008 May 24 70 5 2
2008 May 25 70 5 2
2008 May 26 70 5 2
(NOAA)
