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Tuesday, January 15, 2008

Weekly Radio Propagation Forecast Bulletins

Product: Weekly Highlights and Forecasts
:Issued: 2008 Jan 15 1953 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
07 - 13 January 2008

Solar activity was very low to low. Activity was low on the first day of the period due to a C1/Sf flare at 07/1527 UTC from Region 980 (S07, L = 232, class/area Cso/030 on 02 January). Activity dropped to very low levels during the remainder of the period with no flares
detected.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during 07 - 12 January.

The geomagnetic field was quiet to active on 07 January with localized minor to major storming detected at high latitudes. Quiet to active levels persisted on 08 January. Activity decreased to mostly quiet levels during 09 - 11 January. Activity increased to quiet to active levels on 12 January, then decreased to quiet to unsettled levels on the last day of the period. ACE solar wind measurements indicated a recurrent coronal hole high-speed stream was in progress on 07 January. Peak velocity was 763 km/sec at 07/1320 UTC, followed by a gradual decrease in velocities through 12 January. Interplanetary magnetic field (IMF) variations during the high-speed stream included a peak Bt reading of 5.4 nT at 07/0056 UTC and Bz readings in the + 5 to - 5 nT range. Protons densities ranged from 1 - 2 p/cc during the high-speed stream. The activity increase on 12 January was associated with a solar sector boundary crossing (SSBC) in advance of a recurrent coronal hole high-speed stream. IMF changes associated with the SSBC included a peak Bt reading of 10.4 nT at 13/1603 UTC and a minimum Bz reading of -8.0 nT at 12/1504 UTC. The proton density increase associated with the SSBC reached a peak of 11.4 p/cc at 12/1153 UTC. Solar wind velocities showed an unsteady increase following the SSBC with a peak of 586.3 km/sec observed at 12/2311 UTC.

Forecast of Solar and Geomagnetic Activity
16 January - 11 February 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 16 - 27 January and 03 - 11 February.

The geomagnetic field is expected to be at quiet to unsettled levels during 16 - 17 January. Quiet conditions are forecast for 18 - 31 January. Activity is expected to increase to unsettled to active levels on 01 February due to the onset of a recurrent coronal hole high-speed stream. Quiet to unsettled conditions are expected during 02 - 04 February as the high-speed stream gradually subsides. Quiet conditions are expected during 05 - 08 February. Activity is expected to increase to unsettled to active levels during 09 - 10 February due to another recurrent coronal hole high-speed stream. Quiet to unsettled conditions are expected on 11 February as coronal hole effects subside.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2008 Jan 15 1953 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
#
# 27-day Space Weather Outlook Table
# Issued 2008 Jan 15
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2008 Jan 16 75 10 3
2008 Jan 17 70 8 3
2008 Jan 18 70 5 2
2008 Jan 19 70 5 2
2008 Jan 20 70 5 2
2008 Jan 21 70 5 2
2008 Jan 22 70 5 2
2008 Jan 23 70 5 2
2008 Jan 24 70 5 2
2008 Jan 25 70 5 2
2008 Jan 26 75 5 2
2008 Jan 27 75 5 2
2008 Jan 28 80 5 2
2008 Jan 29 80 5 2
2008 Jan 30 80 5 2
2008 Jan 31 80 5 2
2008 Feb 01 80 15 4
2008 Feb 02 80 12 3
2008 Feb 03 80 10 3
2008 Feb 04 75 10 3
2008 Feb 05 75 5 2
2008 Feb 06 75 5 2
2008 Feb 07 75 5 2
2008 Feb 08 75 5 2
2008 Feb 09 75 15 4
2008 Feb 10 75 15 4
2008 Feb 11 75 10 3
(NOAA)

SIDC Weekly Bulletin
Solar Influence Data Analysis Center
15 January 2008

Solar Activity
Solar activity was low during the entire week. The week started with the decay of the first high-latitude sunspot group of the upcoming solar cycle 24 (AR 981). During the entire week AR 980 remained visible, sometimes showing a few sunspots, but no significant flaring was observed. A large recurring coronal hole dominated the solar equator during the entire week, crossing the central meridian on Jan 11.

Geomagnetic Activity
Geomagnetic conditions ranged from quiet to active conditions (NOAAs estimated Kp <= 4). The week started with still unsettled conditions (Kp <= 3), due to the already declining influence of a recurrent coronal hole. Solar wind speeds decreased during the middle of the week (Jan 10-12), allowing quiet conditions (Kp <= 2), only to increase again due increased solar wind speeds from another recurrent coronal hole, which passed the central meridian on Jan 11, causing unsettled to active conditions (Kp <= 4). (SIDC)