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Tuesday, April 22, 2008

Weekly Propagation Forecast Bulletins

Product: Weekly Highlights and Forecasts
:Issued: 2008 Apr 22 1853 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
14 - 20 April 2008

Solar activity was very low. New-cycle polarity sunspot Region 990 (N27, L = 000, class/area Bxo/010 on 15 April) was numbered on 15 April. It produced a single low-level B-class flare on 16 April as it decayed to a spotless plage region.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during 14 - 16 April.

Geomagnetic field activity was at mostly quiet levels during 14 - 15 April. Activity increased to active levels on 16 April with a brief minor storm period detected at high latitudes. Activity decreased to quiet to unsettled levels during 17 - 18 April. Mostly quiet conditions occurred during the rest of the period. ACE solar wind measurements indicated the onset of a co-rotating interaction region (CIR) on 15 April, in advance of a recurrent coronal hole high-speed
stream (HSS). Interplanetary magnetic field changes during the CIR included increased Bt (peak 14 nT at 16/1424 UTC) and increased Bz variability (minimum -9 nT at 16/1124 UTC). The high-speed stream commenced on 16 April. ACE detected a peak velocity of 610 km/sec at
16/2204 UTC. Velocities decreased during 17 April, but remained elevated during the rest of the period (range: 465 - 584 km/sec).

Forecast of Solar and Geomagnetic Activity
23 April - 19 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 25 April - 13 May.

Geomagnetic field activity is expected to be at active levels during 23 - 24 April due to a recurrent coronal hole high-speed stream. Activity is expected to decrease to unsettled levels during 25 April as the high-speed stream subsides. Quiet conditions are forecast during 24 - 30 April. Activity is expected to increase to unsettled to active levels during 01 - 05 May with minor storm levels likely on 02 May as another recurrent coronal hole high-speed stream
affects the field. Activity is expected to decrease to quiet to unsettled levels during 06 - 07 May as the high-speed stream subsides. Mostly quiet conditions are expected during 08 - 18 May.
Activity is expected to increase to unsettled levels on 19 May.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2008 Apr 22 1853 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 22
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2008 Apr 23 75 15 4
2008 Apr 24 75 12 3
2008 Apr 25 75 8 3
2008 Apr 26 75 5 2
2008 Apr 27 75 5 2
2008 Apr 28 75 5 2
2008 Apr 29 75 5 2
2008 Apr 30 75 5 2
2008 May 01 75 10 3
2008 May 02 70 20 5
2008 May 03 70 15 4
2008 May 04 70 10 3
2008 May 05 70 12 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 75 10 3
(NOAA)