Solar Terrestrial Activity Report

Activity chart

Last major update issued on July 5, 2014 at 07:30 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update July 1, 2014)] [Cycle 24 progress (last update July 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update July 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update July 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update July 5, 2014)]

[POES auroral activity level October 2009 - December 2012]
[Solar polar fields vs solar cycles - updated June 4, 2014]
[Presentations: 3rd SSN Workshop, Tucson, 2013 (pdf) / 4th SSN Workshop, Locarno, 2014]

Recent activity

The geomagnetic field was quiet on July 4. Solar wind speed at SOHO ranged between 285 and 320 km/s.

Solar flux at 20h UTC on 2.8 GHz was 187.6 (increasing 50.7 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 135.4. The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 4.9). Three hour interval K indices: 21222101 (planetary), 11222222 (Boulder).

The background x-ray flux is at the class C1 level.

At the time of counting spots (see image time), spots were observed in 17 active regions using 2K resolution (SN: 496) and 12 active regions using 1K resolution (SN: 288) SDO images on the visible solar disk.

Region 12100 [N10W40] decayed slowly and quietly.
Region 12102 [N12W12] decayed slowly and quietly.
Region 12103 [S11W29] reemerged with penumbra spots.
Region 12104 [S11W01] decayed slowly and lost the magnetic delta structure. An M class flare is still possible.
Region 12106 [N16E07] decayed slowly and quietly.
Region 12107 [S19E11] developed slowly and was mostly quiet. An M class flare is possible.
Region 12108 [S07E29] developed slowly and could produce M class flares.
Region 12109 [S08E48] developed further and has the potential to produce a major flare.
Region 12110 [S16E36] gained a few spots and was quiet.
New region 12111 [N06E65] rotated into view on July 3 and was numbered by SWPC the next day.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3599 [N03W00] lost the leader spots and gained trailing penumbra spots.
S3607 [N12W19] decayed slowly and quietly.
S3609 [S12E13] reemerged with a penumbra spot.
New region S3611 [S30W19] was observed with a penumbra spot.
New region S3612 [S18W26] emerged with a penumbra spot.
New region S3613 [N15W33] emerged with penumbra spots.
New region S3614 [N05E73] rotated into view trailing AR 12111.

C2+ Flares (GOES):

Magnitude Peak time (UTC) Location AR
C2.4 05:37 S08E61 12109
C4.2/1F 14:39 S06E34 12108

Coronal mass ejections (CMEs)

July 2-3: No obviously Earth directed CMEs were observed in LASCO and STEREO imagery.
July 4: A filament eruption near ARs 12102 and S3599 was observed late in the day. With no available LASCO or STEREO imagery it is difficult to tell whether this event resulted in a CME. If it did, the CME will likely be Earth directed.

Coronal holes

Coronal hole history (since October 2002)
Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago

A trans equatorial coronal hole (CH626) could rotate into an Earth facing position on July 5.

Coronal hole map

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is poor. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be quiet on July 5-7. On July 8-9 there is a chance of unsettled intervals due to possible effects from CH626. If a CME was produced by the filament eruption late on July 4 it could arrive at Earth late on July 7 or early on July 8.

Coronal holes (1) Coronal mass ejection (2) M and X class flares (3)
     

1) Effects from a coronal hole could reach Earth within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.

Green: 0-30% probability, Yellow: 30-70% probability, Red: 70-100% probability.

Active solar regions

(Click on image for 2K resolution) Compare to the previous day's image. 0.5K image

When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue is positive.

Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers.

Active region Date numbered
detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlay
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12097 2014.06.22       N14W86           plage
12100 2014.06.25
2014.06.27
9 21 12 N11W40 0030 CRO BXI

area: 0030

S3579 2014.06.26       S10W56           plage
12103 2014.06.26
2014.06.28
  2 1 S10W32 0006   AXX    
S3583 2014.06.27       N00W20           plage
12102 2014.06.27
2014.06.28
13 33 14 N12W09 0070 DAI CAI

area: 0100

12104 2014.06.28 21 59 30 S12W01 0470 DKC DAC beta-gamma
12107 2014.06.28
2014.06.29
9 41 24 S20E10 0290 EHO DHI beta-gamma

area: 0400

location: S19E11

S3590 2014.06.28       S23W03           plage
S3591 2014.06.28       S12W21           plage
S3592 2014.06.28       S11W57           plage
12105 2014.06.28
2014.06.29
      S05W40          
12106 2014.06.29 12 34 18 N14E08 0140 DAO CAI area: 0220

location: N16E07

S3597 2014.06.30       S26W57           plage
12108 2014.06.30
2014.07.01
16 52 28 S08E28 0120 DAI DAC area: 0340

location: S07E29

S3599 2014.06.30   2   N03W00 0004   AXX  
S3600 2014.06.30       S31W58           plage
S3602 2014.07.01       S19W56           plage
S3603 2014.07.01       N06W35           plage
S3605 2014.07.01       N05W57           plage
12109 2014.07.01
2014.07.02
20 51 27 S08E48 0630 EKC EKC beta-gamma

area: 0840

S3607 2014.07.01   1   N12W19 0002   AXX  
12110 2014.07.02
2014.07.03
5 16 7 S17E35 0010 BXO CRO area: 0040
S3609 2014.07.02   1 1 S12E13 0003   AXX    
12111 2014.07.03
2014.07.04
4 8 5 N05E65 0070 CAO CAO  
S3611 2014.07.04   1   S30W19 0003   AXX    
S3612 2014.07.04   1   S18W26 0002   AXX    
S3613 2014.07.04   2   N15W33 0001   AXX    
S3614 2014.07.04   1 1 N05E73 0020   HRX    
Total spot count: 109 326 168  
Sunspot number: 199 496 288  (total spot count + 10 * number of spotted regions)
Weighted SN: 162 377 219  (Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10)
Relative sunspot number (Wolf number): 119 174 158 k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for MSN 2K, k = 0.55 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number Average ap
(3)
Measured 1 AU
2013.02 104.3 101.8 38.0 58.4 (-0.3) 6.11
2013.03 111.3 110.2 57.9 57.5 (-0.9) 10.56
2013.04 124.8 125.9 72.4 57.9 (+0.4) 5.40
2013.05 131.4 134.3 78.7 59.9 (+2.0) 9.73
2013.06 110.1 113.7 52.5 62.6 (+2.7) 12.60
2013.07 115.5 119.3 57.0 65.5 (+2.9) 9.47
2013.08 114.6 118.3 66.0 69.0 (+3.5) 8.27
2013.09 102.6 103.7 36.9 73.1 (+4.1) 5.23
2013.10  132.1 131.2 85.6 75.0 (+1.9) 7.71
2013.11  148.3 145.1 77.6 75.4 (+0.4) 5.68
2013.12 147.7 143.1 90.3 76.0 (+0.6) 4.68
2014.01 157.4 152.4 81.8 (78.2 projected, +2.2) 5.44
2014.02 170.3
(cycle peak)
166.3 102.3 (cycle peak) (79.7 projected, +1.5) 10.70
2014.03 149.9 148.5 91.9 (80.5 projected, +0.8) 4.88
2014.04 143.9 144.8 84.7 (79.7 projected, -0.8) 7.88
2014.05 129.7 132.9 75.2 (77.1 projected, -2.6) 5.75
2014.06 122.0 125.8 71.0 (74.5 projected, -2.6) 6.72
2014.07 171.7 (1)   22.9 (2A) / 177.5 (2B) / 90.4 (2C) (71.5 projected, -3.0) (4.2)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days). The official WDC-SILSO international sunspot number is typically 30-50% lower. 2B) Boulder SN current month average to date. 2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red are based on the definitive international GFZ Potsdam WDC ap indices.

This report has been prepared by Jan Alvestad. It is based on the analysis of data from whatever sources are available at the time the report is prepared. All time references are to the UTC day. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.