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Wednesday, March 26, 2008

Weekly Propagation Forecast Bulletin

Product: Weekly Highlights and Forecasts
:Issued: 2008 Mar 25 2354 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
17 - 23 March 2008


Solar activity was very low. Region 986 (S04, L = 098, class/area Bxo/010 on 17 March) rotated beyond the west limb as a spotless plage region on 19 March. Region 987 (S08, L = 258, class/area Cso/040 on 23 March) rotated onto the visible solar disk on 23 March. This region increased the X-ray background from below A-class to just below B-class. No X-ray flares were observed during the period; however, Region 987 did produce a Sf flare on 23 March
at 2346 UTC.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached high levels all days except for 21 and 23 March.

The geomagnetic field was at quiet levels on 17 March as a coronal hole high speed stream rotated out of geoeffective position. Throughout the remainder of the summary period activity levels were at mostly quiet levels, although there were several intervals of unsettled to active conditions due to sustained southward IMF Bz over several hours. ACE solar wind speeds reached a maximum of 576 km/s on 20 March at 1447 UTC, and a minimum of 405 km/s on 22 March at 0759 UTC. The IMF Bz varied between + 6 nT during the period.

Forecast of Solar and Geomagnetic Activity
26 March - 21 April 2008


Solar activity is expected to be low to moderate. At the time of writing there was a low-level M-class flare in progress from Region 989. This region remains capable of producing M-class activity.
Regions 987 and 988 are also capable of producing C-class flares, and perhaps an isolated M-class flare. On 08 April when Region 989 departs the visible solar disk activity levels should decline to very low levels. Activity levels are expected to increase again to very low to low levels when Region 987 rotates back onto the visible solar disk on 19 April.

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 most of the period. However, the flux may drop to normal levels on 26 March, 02, 05, and 17 - 20 April.

The geomagnetic field is expected to be at unsettled to minor storm levels on 26 - 28 March due to a favorably positioned coronal hole high speed stream. Activity levels should decline to quiet to unsettled levels on 29 - 31 March as the high speed stream rotates out of a geoeffective position. 01 - 03 April a mostly quiet geomagnetic field is expected. On 04 - 11 April a coronal hole high speed stream is expected to influence the geomagnetic field bringing mostly unsettled to active conditions. For the remainder of the period predominately quiet conditions are expected.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2008 Mar 25 2354 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 Mar 25
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2008 Mar 26 85 20 4
2008 Mar 27 90 25 5
2008 Mar 28 90 15 3
2008 Mar 29 90 10 3
2008 Mar 30 90 10 3
2008 Mar 31 90 10 3
2008 Apr 01 90 8 3
2008 Apr 02 90 5 2
2008 Apr 03 90 5 2
2008 Apr 04 85 15 3
2008 Apr 05 85 25 5
2008 Apr 06 80 15 3
2008 Apr 07 80 10 3
2008 Apr 08 75 15 3
2008 Apr 09 70 15 3
2008 Apr 10 70 12 3
2008 Apr 11 70 10 3
2008 Apr 12 70 5 2
2008 Apr 13 70 5 2
2008 Apr 14 70 8 3
2008 Apr 15 70 5 2
2008 Apr 16 70 5 2
2008 Apr 17 70 5 2
2008 Apr 18 70 5 2
2008 Apr 19 75 5 2
2008 Apr 20 80 5 2
2008 Apr 21 85 5 2
(NOAA)