Solar Terrestrial Activity Report    May 24— May 31
May 24 : the geomagnetic field is quiet to unsettled on May 25. Solar wind speed is ranging between 443 and 505 km/sec under the influence of a high speed stream from coronal hole CH97.
Solar flux measured at 20h UTC on 2.8 GHz is 104.0. The planetary A index is 12 (STAR Ap - based on the mean of three hour interval ap indices: 12.4).
Three hour interval K indices: 33233233 (planetary), 33332433 (Boulder).
The background x-ray flux is at the class B2-B3 level.
May 26 : at midnight there is 5 spotted regions on the visible disk. The solar flare activity level is low. A total of 4 C class events is recorded during the day.
May 27 : Region 10613 decayed slowly and quietly.
Region 10615 decayed slowly and quietly.
Region 10618 developed quickly in the leading an trailing spot sections while slow decay is observed in the central section.
The large penumbra in the center split into two and no longer has a magnetic delta structure.
May 29 : A new magnetic delta structure is forming quickly in the leading spot section and could cause M class flares. Flares: C2.9 at 14:52, C2.0 at 17:42, C1.6 at 18:01 and C1.4 at 19:54 UTC.
New region 10619 is emerging in the southwest quadrant.
New region 10620 is emerging in the southeast quadrant to the southeast of region 10618.
Coronal mass ejections (CMEs)
May 30-31: No fully or partly Earth directed CME observed.
Propagations :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor. Propagation along long distance north-south paths is good. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant station tonight: none. At midnight UTC Rádio Papacasa (Brazil) was the best, however, there were at least two other stations from Brazil as well as Radio Cristal del Uruguay. The latter station had a poor signal but was the best between 00:30 and 02:30 UTC when finally Radio Vibración (Venezuela) began to dominate. On 1590.05 kHz an interesting station from Brazil was noted for a long time with mostly non stop (English) oldies. 1510 kHz had two stations from Brazil fighting for dominance, the poorest signal was from Rádio Planalto de Ibiapaba. The strongest station signed off at 01:02 UTC and only a few minutes later WWZN Boston surfaced and gradually got a fair signal. Several stations from Newfoundland (on 540, 590, 650, 740 and 930 kHz) were noted then as well, even WWBR New York on 1130 kHz was audible.

Solar Terrestrial Activity Report    May 31 — June 6
The geomagnetic field is quiet to unsettled on June 1. Solar wind speed ranged between 421 and 478 km/sec. Solar wind speed increased slowly after 17h UTC and another coronal hole flow is currently influencing the geomagnetic field. Active conditions are observed early on June 3.
June 4 :
Solar flux measured at 20h UTC on 2.8 GHz is 84.5. The planetary A index is 11 (STAR Ap - based on the mean of three hour interval ap indices: 11.5). Three hour interval K indices: 33133333 (planetary), 33122323 (Boulder).
The background x-ray flux is at the class A7 level. At midnight there were 3 spotted regions on the visible disk. The solar flare activity level is very low. No C class events are recorded during the day. Region 10621 decayed slowly and quietly.
New region 10626 emerged in the northeast quadrant on June 5 and is numbered the next day by SEC. The region decayed slowly on June 6 and could soon become spotless. New region 10627 emerged in the southeast quadrant and is numbered the next day by SEC. The region is mostly unchanged on June 6.
Coronal mass ejections (CMEs)
June 3-5: No fully or partly Earth directed CMEs observed. A large full halo CME is observed during the morning of June 4, its source is a few days behind the west limb.
Coronal holes :
 A recurrent trans equatorial coronal hole (CH99) is in a geoeffective position on May 31-June2. A small recurrent coronal hole (CH100) in the northern hemisphere is in a geoeffective position on June 4. The darkest areas on the solar disk are likely coronal holes. The geomagnetic field is expected to be quiet to active on June 6-7 due to coronal hole effects and quiet to unsettled on June 8-9.
Propagations :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor to very poor. Propagation along long distance north-south paths is good to excellent. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay.  Radio Vibración (Venezuela) was noted occasionally. Good to excellent propagation towards Brazil was observed from well before local sunrise to nearly one hour after local sunrise. Rádio Inconfidência on 880 kHz had an unusually good signal with other strong stations noted on 740, 760, 840, 860, 930, 1010 kHz. Lots of frequencies had weaker signals from Brazil. Argentina was noted on a few frequencies with the Cordoba station on 700 kHz heard well. A few USA stations had weak signals on frequencies above 1600 kHz and WWZN Boston on 1510 kHz crossed the Atlantic with a fair signal.

Solar Terrestrial Activity Report    June 12 — June 19
Product: Geophysical Alert Message wwv.txt
Issued: 2004 Jun 11 1212 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Environment Center
# Geophysical Alert Message
#Solar-terrestrial indices for 10 June follow.
Solar flux 83 and mid-latitude A-index 9.
The mid-latitude K-index at 1200 UTC on 11 June was 3 (22nT).
No space weather storms were observed for the past 24 hours.
No space weather storms are expected for the next 24 hours.
The geomagnetic field is quiet to unsettled on June 12. Solar wind speed ranged between 392 and 528 km/sec.
Solar flux measured at 20h UTC on 2.8 GHz is 82.5. The planetary A index is 11 (STAR Ap - based on the mean of three hour interval ap indices: 12.0).
Three hour interval K indices: 33223333 (planetary), 33212123 (Boulder).
The background x-ray flux is at the class A4 level.
June 13
At midnight there are 3 spotted regions on the visible disk. The solar flare activity level is very low. No C class events are recorded during the day.
June 14
Region 10622 is mostly unchanged and quiet.
Region 10631 developed slowly and quietly.
New region 10632 rotated into view on June 15 and is numbered the next day by SEC.
Coronal mass ejections (CMEs)
June 16 - 17: No fully or partly Earth directed CMEs observed.
A recurrent coronal hole (CH101) in the southern hemisphere will likely rotate into a geoeffective position.
Processed SOHO/EIT 284 image at 19:05 UTC on June 19. The darkest areas on the solar disk are likely coronal holes.
Forecast
The geomagnetic field is expected to be quiet to unsettled on June 18 - 19 and quiet to active on June 19 - 20 due to a high speed stream from coronal hole CH101.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is very poor. Propagation along long distance north-south paths is fair. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and Radio Vibración (Venezuela). Propagation was best after local sunrise and then favoring signals from Uruguay, Argentina and Venezuela. The best stations were noted on 930, 950, 970, 1010, 1470 and 1590 kHz.

Solar Terrestrial Activity Report    June 27— July 4
The geomagnetic field is quiet to unsettled on June 28.
Solar wind speed ranged between 286 and 364 km/sec. Solar flux measured at 20h UTC on 2.8 GHz is 102.9. The planetary A index is 4 (STAR Ap - based on the mean of three hour interval ap indices: 5.3).
Three hour interval K indices: 00012231 (planetary), 11012121 (Boulder).
The background x-ray flux is at the class B2 level.
June 29
At midnight there are 3 spotted regions on the visible disk. The solar flare activity level is low. A total of 1 C class event is recorded during the day.
June 30
Region 10635 decayed further and will be rotating over the southwest limb today and tomorrow. There is still a magnetic delta structure in the main trailing penumbra. Flare: C2.5 at 11:32 UTC.
Region 10637 developed slowly and has quite a few small spots.
Spotted regions not numbered by NOAA/SEC:
[S424] A new region emerged in the northeast quadrant on July 1. Polarities are currently reversed. Location at midnight: N07E35.
Coronal mass ejections (CMEs)
June 29-July 2: Very few LASCO images available. A weak CME may have been associated with a C1 event in region 10635 on June 30.
Coronal holes :
A recurrent trans equatorial coronal hole (CH103) will rotate into a geoeffective position on June 26-27.
Processed SOHO/EIT 284 image at 13:05 UTC on July 2. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on July 3 and quiet to active on July 4 due to a high speed stream from coronal hole CH103.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor. Propagation along long distance north-south paths is fair to good. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and Radio Vibración (Venezuela). Many stations from Brazil were noted on other frequencies, particularly before 01:30 UTC. Fair to occasionally good signals could be heard on 1510, 1540, 1560 and 1570 kHz. The best trans Atlantic signal, without comparison, was from Rádio Sociedade (Bahia, Brazil) on 740 kHz. As usual 1510 WWZN Boston had the best signal from North America, only a few stations from Newfoundland were heard otherwise.

Solar Terrestrial Activity Report    July 6 — July 13
The geomagnetic field is quiet to unsettled on July 6. Solar wind speed ranged between 394 and 467 km/sec.
Solar flux measured at 20h UTC on 2.8 GHz is 78.2 (the lowest solar flux since the end of the last solar minimum). The planetary A index is 6 (STAR Ap - based on the mean of three hour interval ap indices: 6.9).
Three hour interval K indices: 21012233 (planetary), 12012222 (Boulder).
July 8 : The background x-ray flux is at the class A3 level.
At midnight there are 2 spotted regions on the visible disk. The solar flare activity level is very low. No C class events are recorded during the day.
Region 10639 decayed slowly and quietly. Region 10640 reemerged with spots. Coronal mass ejections (CMEs)
July 9 : No obviously earth directed CMEs are detected. An impressive full halo CME is observed late on July 10. Ejected material is first observed below the south pole in C3 images at 23:18 UTC and surrounded the entire disk shortly after midnight. This CME is likely to have had a backsided origin, about 7 days behind the southwest limb.
Coronal holes :
No significant coronal holes are currently approaching geoeffective positions.
Processed 284 image at 01:06 UTC on July 6. The darkest areas on the solar disk are likely coronal holes.
Forecast :
The geomagnetic field is expected to be quiet to unsettled on July 12.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor. Propagation along long distance north-south paths is good. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant station tonight: Radio Cristal del Uruguay. Radio Vibración was noted as well at times. Post sunrise propagation is interesting with stations from the Buenos Aires area peaking about half an hour after sunrise (Radio Chascomus on 1520 kHz was noted), then swung slightly northwards one hour after sunrise. At that time Radio Ñandutí (Asunción, Paraguay) had an amazingly good signal on 1020.1 kHz and there is another Paraguayan on 970 kHz. From North America WWZN on 1510 kHz is there again with a fair signal, otherwise Newfoundland is heard on 590 and 800 kHz.

Solar Terrestrial Activity Report    September 10 — September 17
The geomagnetic field is quiet on September 10. Solar wind speed ranged between 345 and 358 km/sec.
Solar flux measured at 20h UTC on 2.8 GHz is 131.0. The planetary A index is 4 (STAR Ap - based on the mean of three hour interval ap indices: 5.8).
September 12 : Three hour interval K indices: 11012122 (planetary), 12122122 (Boulder).
The background x-ray flux is at the class B5 level.
At midnight there are 4 spotted regions on the visible disk. The solar flare activity level is low. A total of 3 C class events is recorded during the day.
September 13
Region 10667 decayed very slowly and is quiet.
Region 10669 developed early in the day, then began to decay.
Region 10671 developed quickly during the first half of the day, since then some decay has been observed in the intermediate spots.
September 15 : There is currently a magnetic delta structure in the southern part of the large trailing penumbra. Flare: C2.6 at 06:29 UTC. New region 10672 rotated into view at the northeast limb. It is not yet clear if the southernmost penumbra should be split into a separate region, magnetograms currently indicate that the two parts of the region are not connected, neither in the positive nor in the negative polarity areas.
September 16 : The southern penumbra is the most active and the corona above it is hot. C class flaring with associated coronal mass ejections is likely. Flares: long duration C3.2 peaking at 06:01 and C1.0 at 22:16 UTC.
Coronal mass ejections (CMEs)
September 17 : No obviously Earth directed CMEs are observed. A full halo CME is observed after the C2 event behind the northeast limb on September 18. A CME is observed above the central east limb after the C3 event.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is good. Propagation along long distance north-south paths is very poor. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant station tonight: WLAM Lewiston ME. Apart from a few stations from the Caribbean, a large number of North American stations dominated most of the other 10 kHz spaced frequencies in the MW band. WBBR 1130 had an impressive S9+20dB signal with several other stations topping S9. Greenland on 650 kHz had a strong signal as well.

Solar Terrestrial Activity Report    September 20 — September 27
The geomagnetic field is quiet to active on September 20. Solar wind speed ranged between 542 and 677 km/sec, first under the lingering effects of the CME observed on September 21-22, then under the influence of a high speed stream from coronal hole CH113. September 23 : Solar flux measured at 20h UTC on 2.8 GHz is 109.6. The planetary A index is 14 (STAR Ap - based on the mean of three hour interval ap indices: 15.3). Three hour interval K indices: 43233332 (planetary), 43122312 (Boulder). The background x-ray flux is at the class B3 level. September 24 : At midnight there are 3 spotted regions on the visible disk. The solar flare activity level is low. A total of 4 C class events is recorded during the day. A C1.3 long duration event peaking at 20:55 UTC had its origin behind the southwest limb. Region 10672 developed new spots to the immediate north and northeast of the leading penumbrae early in the day. Then the region began to decay and lost penumbra and spots, particularly in the trailing spot section. M class flares are possible. Flares: C2.7 at 07:49, C1.1 at 17:13, C1.1 at 17:51 UTC. September 25 : New region 10673 rotated fully into view at the southeast limb. The region doesn't appear to be complex spotwise, however, magnetograms hint at some complexity and the region is probably capable of C class flaring. Spotted regions not numbered by NOAA/SEC: [S453] This unipolar region emerged on September 15 in the northeast quadrant with a single, small spot. Coronal mass ejections (CMEs)
September 26-27: No obviously Earth directed CMEs are observed.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor. Propagation along long distance north-south paths is poor. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). On other frequencies Puerto Rico was noted on 580, 1600 and 1660 kHz while the most usual stations from Newfoundland and Nova Scotia had fair signals as early as 23:30 UTC.

Solar Terrestrial Activity Report    September 28 — October 5
The geomagnetic field is quiet to slightly unsettled on September 28. Solar wind speed ranged between 357 and 385 km/sec. Solar flux measured at 20h UTC on 2.8 GHz is 89.5. The planetary A index is 5 (STAR Ap - based on the mean of three hour interval ap indices: 6.1). Three hour interval K indices: 01022322 (planetary), 10033211 (Boulder).
September 29 : The background x-ray flux is at the class A5 level. September 30 : at midnight there are 2 spotted regions on the visible disk. The solar flare activity level is very low. No C class events are recorded during the day
October 1 : region 10673 is quiet and stable. New region 10675 rotated into view at the southeast limb.
Coronal holes : No obvious coronal holes are currently approaching geoeffective positions. There is a large, mostly poorly defined coronal hole in the northern hemisphere, however, its southward extension does not appear to reach far enough south to become geoeffective.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is fair to poor at night and fair during local sunrise. Propagation along long distance north-south paths is poor. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). Several stations from the Canadian Atlantic provinces and the US northeast were observed throughout the MW band with poor to fair signals. The best signals were from CJYQ on 930 and VOCM on 590 kHz.

Solar Terrestrial Activity Report    October 9 — October 16
The geomagnetic field is quiet to unsettled on October 8 - 9. Solar wind speed ranged between 275 and 362 km/sec, slowly increasing early in the day due to a low speed stream from coronal hole CH117.
October 10 : Solar flux measured at 20h UTC on 2.8 GHz is 90.7. The planetary A index is 7 (STAR Ap - based on the mean of three hour interval ap indices: 7.6). Three hour interval K indices: 13212213 (planetary), 02213322 (Boulder).
October 12 : The background x-ray flux is at the class B1 level.
At midnight there is 1 spotted region on the visible disk. The solar flare activity level is very low. No C class events is recorded during the day.
October 13 : New region 10680 is numbered as SEC did not consider the emerging flux areas part of region 10678. The region developed fairly quickly and has little or no separation between the opposite polarity fields. The region is rotating over the northwest limb.
Coronal mass ejections (CMEs)
October 14 - 15 : No obviously Earth directed CMEs observed. A trans equatorial coronal hole (CH117) is in a geoeffective position on October 3-4. A recurrent coronal hole (CH118) in the southern hemisphere is in a geoeffective position on October 14.
A southward (poorly defined) extension of the large northern polar coronal hole may would be in a geoeffective position on October 15. The geomagnetic field is expected to be quiet to unsettled on October 16 due to minor effects from coronal hole CH117. Quiet is likely on October 17 with unsettled to active conditions possible on October 18 - 19 due to a coronal flow from coronal hole CH118.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is fair to good. Propagation along long distance north-south paths is poor. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant station tonight: WLAM Lewiston ME. On other frequencies propagation is best towards the northeastern part of the USA and the Canadian Atlantic provinces. Some stations from the Caribbean are noted as well.

Solar Terrestrial Activity Report    October 27 — November 3
The geomagnetic field is quiet to active on October 27. Solar wind speed ranged between 418 and 509 km/sec under the influence of a high speed stream from coronal hole CH120. This coronal hole flow becomes less influential during the latter half of the day.
October 29 : Solar flux measured at 17h UTC on 2.8 GHz is 139.6. The planetary A index is 13 (STAR Ap - based on the mean of three hour interval ap indices: 12.6).
October 30 : Three hour interval K indices: 23343221 (planetary), 23343321 (Boulder).
The background x-ray flux is at the class B3 level.
At midnight there are 7 spotted regions on the visible solar disk. The solar flare activity level is low. A total of 9 C class events is recorded during the day.
November 1 : Region 10684 decayed further and lost nearly all trailing spots.
Region 10687 decayed significantly, particularly in the leading and central spot sections.
November 2 : A minor M class flare is possible. Flares: C2.4 at 07:16, C2.3 at 10:07, C6.8 at 10:31, C2.1 at 14:17, C4.4 at 14:42, C2.4 at 22.17 and C2.0 at 23:03 UTC.
Region 10689 was quiet and stable.
Region 10690 was quiet and stable.
Region 10691 decayed in the trailing spot section and lost its magnetic delta structure. Flare: C4.2 at 02:52 UTC.
Region 10692 decayed somewhat as the opposite polarity areas becomes better separated.
Spotted regions not numbered by NOAA/SEC:
[S466] This region emerged on October 25 in the northeast quadrant. Location at midnight: N16E62.
Coronal mass ejections (CMEs)
November 2-3 : No obviously Earth directed CMEs observed.
Coronal holes : A coronal hole (CH121) in the southern hemisphere is in a geoeffective position on October 28-29.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is fair to poor and improving. Propagation along long distance north-south paths is poor. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela) and Radio Cristal del Uruguay at 01h UTC, later on WLAM Lewiston ME was noted as well. On other frequencies propagation was best towards the easternmost parts of the USA and Canada.
October 11 - 12 :
An extremely rare event has been produced, the sun did not has the least sunspot on surface (Wolf number = zero).
specialists in NASA, think that the descent of the cycle should much faster than be envisaged. It seems to them that the minimum would be at the end of 2006 and the next maximum in 2010.
Source: CDXC

Solar Terrestrial Activity Report    November 24 - December 1
The geomagnetic field is quiet to active on November 24. Solar wind speed ranged between 460 and 582 km/sec, slowly decreasing after 05h UTC. Solar flux measured at 20h UTC on 2.8 GHz is 106.3. The planetary A index is 10 (STAR Ap - based on the mean of three hour interval ap indices: 10.5). November 25 : Three hour interval K indices: 14431221 (planetary), 23432121 (Boulder).
The background x-ray flux is at the class B3 level.
November 26 : At midnight there are 3 spotted regions on the visible solar disk. The solar flare activity level is low. A single C class event is recorded during the day. This is a very long duration C1.1 event peaking at 07:57 and with an origin behind the southeast limb. November 27 : Region 10701 decayed slowly and quietly and will rotate out of view at the southwest limb today.
Region 10704 decayed slowly.
November 28 : [S477] This region is first observed on November 14, then lost its spots. A single spot is becoming visible on Nov. 28. Slow development is observed on November 29. Location at midnight: S04W52.
Coronal mass ejections : (CMEs)
November 27-28: No obviously Earth directed CMEs observed.
Coronal holes :
Recurrent coronal hole CH128 in the southern hemisphere is in a geoeffective position on November 30 -December 1.
Forecast :
The geomagnetic field is expected to be quiet to unsettled on November 26-27. A high speed stream from coronal hole CH128 is likely arrive on November 28 and cause unsettled to active conditions that day becoming quiet to active on November 29-30 Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is very poor. Propagation along long distance north-south paths is poor to fair. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: Radio Cristal del Uruguay. Radio Vibración (Venezuela) was heard weakly at times. On other frequencies propagation was best towards Brazil with a strong signal from Rádio Metropolitana on 930 and an unidentified station with religious programming on 580 kHz. The only North American station I could hear was WWZN Boston on 1510 kHz.

Solar Terrestrial Activity Report  July 17 - July 24
Recent activity
The geomagnetic field is quiet to unsettled on July 17. Solar wind speed ranged between 360 and 460 (all day average 429) km/sec. A minor solar wind shock is observed at 00:50 UTC at ACE (01:23 UTC at SOHO) on July 17. This is likely the arrival of the CME observed on July 19.
July 20 : solar flux measured at 20h UTC on 2.8 GHz is 76.3. The planetary A index is 9 (STAR Ap - based on the mean of three hour interval ap indices: 8.9).
Three hour interval K indices: 22211333 (planetary), 33412333 (Boulder).
The background x-ray flux is at the class A7 level.
July 21 : at midnight there is 1 spotted region on the visible solar disk. The solar flare activity level is moderate. A total of 4 C and 1 M class events is recorded during the day.
July 22 : Spotted regions not numbered or wrongly numbered :
[S570] This region emerged in the southwest quadrant on July 13 just west of region 10790. The region developed further on July 18 - 21 with no or poor separation between the opposite polarity areas in the trailing part of the region. The leading part of the region rotated out of view during the latter half of July 22. Location at midnight: S11W81. Flares: C1.3 at 02:52, M1.0 at 03:38, C1.8 at 06:34, C2.2 at 07:14 and C4.8 at 11:21 UTC.
Coronal mass ejections :
July 17: A large, fast and very wide full halo CME is observed after the X1 event in region 10786.
July 18 - 23 : No obvious partly or fully Earth directed CMEs are observed.
Coronal holes :
A recurrent trans equatorial coronal hole (CH175) will rotate into an Earth facing position on July 18 - 24.
Forecast :
The geomagnetic field is expected to be quiet to active on July 17 due to CME effects. Quiet to unsettled is likely on July 18-19. Late on July 21 or early on July 24 a high speed stream from CH175 is likely to arrive and could cause unsettled to minor storm conditions until July 21 or 22.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor. Propagation along long distance north-south paths is poor to fair. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and Radio Vibración (Venezuela). Weak signals from Argentina were observed on a number of frequencies including 1620 (Radio Vida), 1630 (AM Restauración), 1650, 1680 and 1690 kHz. From North America the Newfoundland stations on 590, 710 and 930 kHz had weak signals.

ALERT 7 SEPTEMBER -> the most important sun exlposion since report history
The geomagnetic field is inactive to unsettled on September 6. Solar wind speed ranged between 432 and 468 (all day average 450) km/sec.
Solar flux measured at 20h UTC on 2.8 GHz is 83.4. The planetary A index is 9 (STAR Ap - based on the mean of three hour interval ap indices: 8.6).
Three hour interval K indices: 32422312 (planetary), 33122332 (Boulder).
The background x-ray flux is at the class B5 level.
At midnight there are 2 spotted regions on the visible solar disk. The solar flare activity level is moderate. A total of 3 C and 1 M class events is recorded during the day. Old region 10798 behind the southeast limb produced a long duration C1.3 event peaking at 07:52, a C1.3 flare at 10:18 and a very long duration M1.4 event peaking at 22:02 UTC. This region could produce very significant X class proton flares. Background proton levels have been increasing slowly over the last day as this region approached the limb.
Region 10805 decayed slowly and quietly. [S590] This region rotated partly into view at the northeast limb on September 6. Location at midnight: N10E84. Comment added at 18:22 UTC on September 7: Old region 10798 produced one of the largest flare ever recorded today at 17:40 UTC. GOES Xray sensors displayed signs of saturation. While GOES12 has this as an X17 flare the peak is likely close to X20. Previous CMEs from this region have been very fast. Although this occurred at the southeast limb, a significant sideways impact at Earth could occur as early as before midnight tomorrow, although more likely on September 9. Active to severe geomagnetic storming is possible.
Coronal mass ejections (CMEs)
September 4-6: A CME was observed over the west limbs following a long duration C2 event in region 10803 during the afternoon on September 4. A backsided, large full halo CME was observed after the LDE in old region 10798 behind the southeast limb near noon on September 5.
Coronal holes :
A poorly defined recurrent coronal hole (CH186) in the northern hemisphere near the equator is in an Earth facing position on September 5-6. A recurrent trans equatorial coronal hole (CH187) will rotate to an Earth facing position on September 9-11.
Forecast :
The geomagnetic field is expected to be quiet to unsettled on September 7 and quiet to active on September 8-9 due to effects from CH186. Quiet conditions are likely on September 10-11 becoming quiet to active on September 12-13 when a high speed stream from CH187 reaches Earth.
Propagation
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is very poor. Propagation on long distance northeast-southwest paths is good. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and LT28 Rafaela Argentina. Several stations from Argentina were noted with unusually good signals during the night: 1030, 1070 and 1190 kHz were the best.

The geomagnetic field is quiet to unsettled on September 8. Solar wind speed ranged between 332 and 401 (all day average 360) km/sec.
Solar flux measured at 20h UTC on 2.8 GHz is 94.1. The planetary A index is 8 (STAR Ap - based on the mean of three hour interval ap indices: 7.8).
Three hour interval K indices: 32111223 (planetary), 22113322 (Boulder).
The background x-ray flux is at the class C2 level.
At midnight there are 2 spotted regions on the visible solar disk. The solar flare activity level is high. A total of 6 C, 2 M and 1 X class events is recorded during the day.
Region 10808 is large, compact and very complex with multiple magnetic delta structures within the same penumbra. There is a high likelihood of further X class flaring. Flares: C2.9 at 11:17, C2.0 at 12:58, C4.0 at 14:36, C1.9 at 14:52, M2.1 at 17:03, M2.1 at 20:29 and major X5.4 at 21:06 UTC. The X flare was associated with a type IV radio sweep and a large CME. (So far on September 9 the region has produced these flares: C6.2 at 00:32, M1.0 at 02:17, M1.1 at 02:35, X1.1 at 03:00 and M1.3 at 03:43 UTC)
New region 10809 rotated into view at the northeast limb on September 6 and is noticed by SEC two days later.
Coronal mass ejections :
September 6: A CME is observed over the west limbs following a long duration C2 event in region 10803 during the afternoon on September 4. A backsided, large full halo CME is observed after the LDE in old region 10798 behind the southeast limb near noon on September 5.
September 7: monster X flare in region 10808, previous CMEs from this region (while on the backside of the sun) were all wide and fast. A glancing impact on Earth is possible from late on September 8 until the afternoon on September 9.
September 8: Another large CME may have been associated with the X5 flare in region 10808 during the evening. This CME could reach Earth on September 10.
Coronal holes :
A poorly defined recurrent coronal hole (CH186) in the northern hemisphere near the equator was in an Earth facing position on September 5-6. A recurrent trans equatorial coronal hole (CH187) will rotate to an Earth facing position on September 9-11.

The geomagnetic field is quiet to active on September 9. Solar wind speed ranged between 311 and 549 (all day average 380) km/sec. A solar wind shock is observed at SOHO at 13:10 UTC. This is the arrival of the CME originating from the limb event in region 10808 late on September 7. Solar flux measured at 17h UTC on 2.8 GHz is 99.2 (the measurements at both 20 and 23h UTC are unusable due to strong flare enhancement). The planetary A index is 17 (STAR Ap - based on the mean of three hour interval ap indices: 17.0).
Three hour interval K indices: 12014444 (planetary), 32124554 (Boulder).
The background x-ray flux is at the class C1-C2 level.
At midnight there are 3 spotted regions on the visible solar disk. The solar flare activity level is very high. A total of 8 C, 6 M and 3 X class events was recorded during the day.
Region 10808 is large, compact and very complex with 4 magnetic delta structures within the same penumbra. In particular an extreme delta is in the southern central part where an area of negative polarity is nearly completely encircled by positive polarity. In this area there appears to be no separation between the opposite polarity umbrae. Further proton X class flare are very likely. Flares: C6.2 at 00:32, M1.0 at 02:19, M1.1 at 02:36, X1.1 at 03:00, M1.3 at 03:43, M1.8 at 05:03, M6.2/1F at 05:48, C3.7 at 08:26, C3.1 at 09:18, C4.8 at 09:31, X3.6 at 09:59, C3.0 at 12:47, C4.2 at 15:26, C2.8 at 15:43, C1.0 at 16:38, M1.9 at 17:51 and finally a major long duration X6.2/2B proton event peaking at 20:04 UTC. The X6 event was associated with a moderate type II and a strong type IV radio sweep.
Region 10809 is quiet and stable.
[S591] This region emerged in the southeast quadrant on September 9. Location at midnight: S05E25.
Coronal mass ejections :
September 8: Another large CME may have been associated with the X5 flare in region 10808 during the evening. This CME could reach Earth on September 10.
September 9: they are strongly contaminated by the ongoing proton storm. Several CMEs (where the main body of the ejected material is not aimed at Earth) are likely to have been produced by the multitude of M and X class events in region 10808. Glancing impacts are possible on September 11. The CME associated with the long duration X6 event is likely to be more significant than the others.
Coronal holes :
A recurrent trans equatorial coronal hole (CH187) will rotate to an Earth facing position on September 9-11.
Forecast :
The geomagnetic field is expected to be quiet to minor storm on September 10 and active to major storm September 11-22 with severe storming likely on some days due to a near continuous stream of ejected material from region 10808. During the same time interval intense particle storms could have a huge impact on propagation conditions over most middle and high latitude paths.
Propagation :
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is useless. Propagation on long distance northeast-southwest paths is poor to fair. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay after midnight, earlier Rádio Rural AM de Parelhas (Brazil). Several weak to fair signals from stations in Argentina and Uruguay were observed.