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Tuesday, July 09, 2013

Weekly Propagation Forecast Bulletins


Product: Weekly Highlights and Forecasts
:Issued: 2013 Jul 08 0623 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 July 2013

Solar activity was at low to moderate levels. Low levels were observed on 01 - 02 July, predominately from new Region 1785 (S11, L=006, class/area Ekc/680 on 05 July). Activity briefly increased to moderate levels on 03 July when new Region 1787 (S15, L=349, class/area Eai/170 on 05 July) produced an M1/Sf at 03/0708 UTC. Weak, low frequency radio emissions accompanied this event including a Type II spectral sweep with an estimated shock velocity of 1033 km/s. Activity levels returned to low on 04 July and remained there for the balance of the period. Numerous C-class activity, ranging from C1 to C8, was observed from Regions 1785 and 1787 during this time frame. At 06/1601 UTC, a faint, slow-moving coronal mass ejection (CME) was detected in SOHO/LASCO C2 imagery. WSA-ENLIL model output suggested the CME had an Earth-directed component with an arrival time expected for early on 10 July. The source location of this CME was uncertain. 

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 Jul and at moderate levels on 06 - 07 Jul. A
maximum flux of 6,620 pfu was observed at 04/1620 UTC. 

Geomagnetic field activity ranged from quiet to active levels. The period began with unsettled periods early on 01 July and relaxed to quiet levels through late on 05 July. During this time frame, ACE wind measurements indicated a gradual decay in speed from about 550 km/s to near 350 km/s. The interplanetary magnetic field (IMF) Bt ranged from 3 to 5 nT while the Bz component varied between +3 to -5 nT. The Phi component was in a predominately positive (away) orientation through late on the 5th. At about 05/1900 UTC, Bz gradually turned southward and remained so through about 07/0200 UTC. Bz reached a maximum of -13 nT at 06/0253 UTC while Bt peaked at 13 nT. The Phi angle switched to a predominately negative
(toward) orientation at about 06/0500 UTC and remained negative through about 07/1600 UTC. The geomagnetic field responded with unsettled to active conditions with minor to major high latitude storming through early on 07 July. This discontinuity in ACE, and the related geomagnetic activity, was possibly due to effects from the 30 June CME. For the balance of the period, the geomagnetic
field returned to quiet levels as Bz turned mostly positive to about +5 nT and wind speed further decayed to end-of-period values near 300 km/s. 

Forecast of Solar and Geomagnetic Activity 08 July - 03 August 2013

Solar activity is expected to be at predominately low levels with a chance for M-class activity through the outlook period. 

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 from 08 - 19 July and moderate to high levels from 20 July - 03 Aug. 

Geomagnetic field activity is expected to be unsettled to active levels from 08 - 11 July due to combined effects from a positive coronal hole high speed stream (CH HSS) and effects from the 06 July CME. Predominately quiet conditions are expected from 12 - 16 July. Unsettled to active conditions are expected from 17 - 21 July as a recurrent, negative CH HSS rotates into a geoeffective position.
Mostly quiet conditions are expected from 22 July - 03 August. 

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2013 Jul 08 0623 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 2013-07-08
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2013 Jul 08     125          10          3
2013 Jul 09     130          10          3
2013 Jul 10     135          15          4
2013 Jul 11     140           8          3
2013 Jul 12     140           5          2
2013 Jul 13     135           5          2
2013 Jul 14     120           5          2
2013 Jul 15     125           5          2
2013 Jul 16     120           5          2
2013 Jul 17     120          10          3
2013 Jul 18     125          15          4
2013 Jul 19     125          15          4
2013 Jul 20     125          15          4
2013 Jul 21     120          15          4
2013 Jul 22     110           8          3
2013 Jul 23     105           5          2
2013 Jul 24     100           5          2
2013 Jul 25     100           5          2
2013 Jul 26     105           5          2
2013 Jul 27     110           5          2
2013 Jul 28     110           5          2
2013 Jul 29     120           5          2
2013 Jul 30     125           5          2
2013 Jul 31     130           5          2
2013 Aug 01     135           5          2
2013 Aug 02     135           5          2
2013 Aug 03     130           5          2
(NOAA)