Average daily sunspot numbers increased slightly this week from 111.4 to 113.3, but average daily solar flux declined by 22 points from 155.4 to 133.4. Although there seems to be no shortage of sunspots, they are anemic and not magnetically complex, and thus radiation from the spots is feeble, indicated by lower solar flux values.
Predicted solar flux for the near term is 135 on January 24, 130 …
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Recent solar activity took a healthy jump this week, with the average daily sunspot number increasing nearly 48 points to 126.9, a positive change of 60 percent compared to the previous week. Average daily solar flux was up 16.4 points to 126.5.
The daily sunspot number rose to 148 on October 15, then 166 on October 17, the highest it’s been since May 15-17 when it was 186, 212 and 198.
Average …
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Our sun is still very quiet, but solar flux and sunspot numbers were higher this week than last. Average daily sunspot numbers rose from 42.3 to 75.6, and average daily solar flux rose from 95.3 to 109.6. There were no big geomagnetic events this week.
Predicted solar flux is 110 on September 27 through October 2, then 105, 100, 95, 100, 105 and 100 on October 3-8, 95 on October 9-10, then 100, …
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Conditions were quieter again this week. Average daily sunspot numbers declined from 77 to 69, and average daily solar flux was off by 9.5 points to 106.9, when compared to the previous seven days, August 22-28.
Predicted solar flux for the near term is 105 on September 6-10, 100 on September 11-12, 110 on September 13, 120 on September 14-15, 115 on September 16-17, 110 on September 18, 105 on …
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Solar activity slipped this week, with the average daily sunspot number declining nearly 50 points to 77 and average daily solar flux down nearly 10 points to 116.4. In fact, those “nearly” numbers were 49.9 and 9.9.
The latest solar flux predictions from NOAA/USAF (Thursday, August 29, 2013):
August 30-September 1: 108, 105 and 108
September 2-3: 110
September 4-5: 112
September 6-7: 115 and 120
Se…
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Again this week, solar activity was unchanged, with average daily sunspot numbers slipping from 85.4 to 85, and average daily solar flux increasing 4.4 points to 111.7. Geomagnetic conditions were stable.
The latest solar flux prediction from USAF/NOAA has flux values of 125 on August 16, 130 on August 17-18, 120 on August 19-20, 110 on August 21-23, 105 on August 24, 110 on August 25-26, 115 on…
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Solar indicators barely moved this week, with average daily sunspot numbers up 5.8 points to 85.4, and average daily solar flux down 2.4 points to 107.3.
Predicted solar flux for the next week is low, with the predicted average for Thursday August 8 through Wednesday August 14 at 104.9, a little lower than the 107.3 average for this past week.
Solar flux is predicted at 105 on August 9-16, 110 on…
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The average daily sunspot numbers sank nearly 50 points this week to 94.3, while the average daily solar flux was down more than 16 points to 117.8. The geomagnetic indices were quite high, due to a solar wind storm. Sunspot numbers for May 23-29 were 117, 99, 107, 92, 87, 75 and 83, with a mean of 94.3. The 10.7 centimeter flux was 134.5, 127.3, 121.3, 120, 110.1, 104.8 and 106.9, with a mean …
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Both the average daily sunspot numbers and the solar flux were up this week, with the sunspot numbers rising nearly 57 points to 138.1, and the average daily solar flux up more than 25 points to 138.8. Paired with the average daily planetary A index dropping from 9.4 to 4.1, this is great news for HF propagation. On April 8, the daily sunspot number reached 162; two days later, it was at 163. T…
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Solar activity increased over this past week, with the average daily sunspot numbers up 32 points to 81.6, while the average daily solar flux increased more than 16 points to 113.4. The geomagnetic field was active on March 29 due to solar wind. Sunspot numbers for March 28-April 3 were 49, 73, 70, 83, 84, 103 and 109, with a mean of 81.6. The 10.7 centimeter flux was 98.7, 105.1, 108.4, 113.3,…
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Both the averages of daily sunspot numbers and solar flux rose, with the sunspot numbers up nearly 36 points to 93.3, and the solar flux up nearly 12 points to 112.6. The most active geomagnetic day was Friday, March 1, when the planetary A index was 27 and the mid-latitude A index was 23; Alaska’s high latitude College A index was a whopping 64.
Sunspot numbers for February 28-March 6 were 63, …
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This past week, there was a decline in the solar and geomagnetic indices: The average daily sunspot number dropped nearly 21 points to 57.7, while the average daily solar flux softened by 4.7 points to 100.9 and the average daily planetary A index declined 6.4 points to 5.1. This isn’t much of a change, but geomagnetic activity was low already, and this is even lower.
Sunspot numbers for Februar…
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There was a modest rise in the average daily sunspot numbers over the past seven days, rising 27 points to 78.3, while the average daily solar flux was up marginally, only 1.6 points to 105.6. The geomagnetic indices also went up, with the planetary A index rising from 5.6 to 6.4, and the middle latitude A index rising from 5.1 to 6. There was a more substantial rise in both the solar flux and …
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The average daily sunspot numbers hardly changed from last week and the week prior, but the average daily solar flux bounced back to about the level it was from two weeks ago: The average daily sunspot numbers were down 5 points to 50.7, while the average daily solar flux was up 7.7 points to 106.4. Sunspot numbers for January 31-February 6 were 47, 65, 54, 79, 30, 41 and 39, with a mean of 50….
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The average daily sunspot numbers this past week dropped nearly 73 points to 56.4, while the average daily solar flux declined nearly 47 points to 110.7. The average geomagnetic indices were up about 50 percent, but it was still very quiet. The difference was mostly due to events on January 17 when the planetary A index was 13 — higher than in recent weeks, but still moderate. The cause of the…
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The average daily sunspot numbers fell 13.5 points this week, from 61.1 to 47.6, while the average daily solar flux was about the same this week as last, rising 1.1 points to 102.7. Geomagnetic indices were even quieter this week than last. Sunspot numbers for December 6-12 were 49, 23, 35, 40, 49, 55 and 82, with a mean of 47.6. The 10.7 centimeter flux was 97.4, 97.1, 101.1, 103.7, 104, 103.7…
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Solar activity declined again this week, with the average daily sunspot numbers dropping 17.8 points, from 78.9 to 61.1, while the average daily solar flux declined 19.4 points, from 121 to 101.6. Sunspot numbers for November 29-December 5 were 89, 67, 49, 43, 44, 58 and 78, with a mean of 61.1. The 10.7 centimeter flux was 113.1, 110.6, 101.7, 97.7, 96.6, 96.2 and 95.5, with a mean of 101.6. T…
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The average daily sunspot number for the week was down nearly 38 percent to 78.9, compared to last week’s average of 126.9. The average daily solar flux dropped nearly 13 percent, to 121 from 138.9. The seven-day reporting period for these data ran from November 22-28. Sunspot numbers for November 22-28 were 93, 85, 87, 64, 81, 76 and 66, with a mean of 78.9. The 10.7 centimeter flux was 127.7,…
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In November 16 edition of the Solar Update, we reported that the average daily sunspot number on November 8-14 was 104.9. In the next seven day reporting period — November 15-21 — the average was 126.9, making for a nice increase; with solar flux, the average over the previous period was 129.5. In the most recent period, the average daily sunspot number increased to 138.9. In the four days si…
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Solar activity retreated again this week, with the average daily sunspot numbers declining 8.7 points to 49.7, while the average daily solar flux was down nearly 20 points to 97.2. Sunspot numbers for November 1-7 were 48, 34, 35, 46, 47, 61 and 77, with a mean of 49.7. The 10.7 cm flux was 98.4, 96.5, 93.3, 95, 96.6, 98.7 and 101.7, with a mean of 97.2. The estimated planetary A indices were 1…
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Solar activity quieted this week, with the average daily sunspot numbers down nearly 37 points to 58.4 and the average daily solar flux declining 27 points to 116.9. Sunspot numbers for October 25-31 were 58, 71, 59, 55, 75, 56 and 35, with a mean of 58.4. The 10.7 cm flux was 130, 130.7, 121.7, 117, 108.4, 106.3 and 104.2, with a mean of 116.9. The estimated planetary A indices were 4, 4, 4, 3…
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The average daily sunspot numbers rose this week from 56 to 81.3, while the average daily solar flux increased from 101.4 to 129.7. Sunspot numbers for September 20-26 were 68, 74, 46, 57, 90, 121 and 113, with a mean of 81.3. The 10.7 cm flux was 117.4, 116.9, 124.5, 133.6, 136.6, 139.8 and 139.2, with a mean of 129.7. The estimated planetary A indices were 9, 5, 4, 2, 2, 2 and 6, with a mean …
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The average daily sunspot numbers dropped this week, from 83.1 to 56, while the average daily solar flux declined from 118.9 to 101.4. Sunspot numbers for September 13-19 were 44, 44, 53, 77, 51, 61 and 62, with a mean of 56. The 10.7 cm flux was 99.1, 100.5, 97.5, 97.3, 101.5, 104.3 and 109.8, with a mean of 101.4. The estimated planetary A indices were 6, 5, 6, 7, 6, 8 and 14, with a mean of …
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Solar activity retreated this week, with the average daily sunspot numbers off nearly 46 points — about 35 percent — to 83.1, while the average daily solar flux declined 18 points to 118.9. Sunspot numbers for September 6-12 were 112, 110, 70, 87, 62, 73 and 68, with a mean of 83.1. The 10.7 cm flux was 128, 133.4, 128.6, 123, 111.3, 105.1 and 102.6, with a mean of 118.9. The estimated planet…
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There was a surprising jump in solar activity occurred this week: The average daily sunspot numbers rose nearly 55 points (that’s almost 74 percent) to 128.7, while the average daily solar flux values were up more than 28 points to 136.9. Sunspot numbers for August 30-September 5 were 118, 144, 120, 108, 156, 150 and 105, with a mean of 128.7. The 10.7 cm flux was 127.8, 130.5, 145.6, 142.3, 14…
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Although solar activity is quite low, there was an increase in sunspot numbers and in the solar flux over the past week. The average daily sunspot numbers were up nearly 20 points — about 36 percent — to 74.1, while the average daily solar flux increased nearly 13 points to 108.7. Sunspot numbers for August 23-29 were 49, 69, 70, 78, 85, 73 and 95, with a mean of 74.1. The 10.7 cm flux was 96…
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The weak solar activity continues: The average daily sunspot numbers for the seven days of August 16-22 were down 23 points — 30 percent — to 54.6, while the average daily solar flux dropped a little over 16 percent — 18.7 points — to 96. These figures offer a comparison between August 9-15 and the latest reporting period of August 16-22. Sunspot numbers for August 16-22 were 34, 42, 56, 69…
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There was a big drop in solar activity over the past week, with the average daily sunspot numbers declining nearly 42 points to 77.6, and the average daily solar flux down 20 points to 114.7. Sunspot numbers for August 9-15 were 124, 105, 98, 76, 62, 46 and 32, with a mean of 77.6. The 10.7 cm flux was 131.2, 125.4, 119.7, 112.3, 108.1, 105.8 and 100.7, with a mean of 114.7. The estimated plane…
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The average daily sunspot numbers rose more than 20 points this week — about 20 percent — to 119.4, while the average daily solar flux was up 3 points to 134.7. Sunspot numbers for August 2-8 were 126, 160, 140, 107, 108, 96 and 99, with a mean of 119.4. The 10.7 cm flux was 134.6, 139.7, 138.7, 134, 134.1, 128.5 and 133.3, with a mean of 134.7. The estimated planetary A indices were 16, 7, 7…
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Solar activity rose moderately this week, with the average daily sunspot numbers up nearly 3 points to 120.9, and the average daily solar flux rising more than 28 points to 166.8. There was quite a bit of geomagnetic activity — the most happening on July 9 — when the mid-latitude A index reached 29, the planetary A index was 30 and Alaska’s college A index was 60. Sunspot numbers for July 5-1…
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Sunspot numbers seemed to be in a free-fall this week: The average daily sunspot numbers declined more than 29 points to 87, while the average daily solar flux fell 6.2 points to 126.2. Sunspot numbers for June 14-20 were 114, 113, 110, 96, 66, 64 and 46, with a mean of 87. The 10.7 cm flux was 148.6, 144.9, 134.5, 124, 118, 109.9 and 103.7, with a mean of 126.2. The estimated planetary A indic…
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Solar activity was lower this week, although for the past few days, both the sunspot numbers and solar flux were rising. The average daily sunspot numbers declined more than 14.3 points to 116.1, while the average daily solar flux was off by 14.5 points to 115.9. There were five new sunspot groups this week: two each on June 9-10, and one more on June 13. Sunspot numbers for June 7-13 were 98, …
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The average daily sunspot numbers increased about 60 percent during the past week (May 31-June 6), when compared to the previous seven days (May 24-30). The increase was 48.5 points, from 81.9 to 130.4. The average daily solar flux was also up: 18.6 points from 111.6 to 130.2. Sunspot numbers for May 31-June 6 were 76, 151, 113, 133, 155, 154 and 131, with a mean of 130.4. The 10.7 cm flux was …
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The average daily sunspot numbers sank more than 28 points this week (nearly 26 percent) to 81.9, while the average daily solar flux declined more than 16 points to 111.6. This is for the seven days of May 24-30, and is compared to the previous seven days, May 17-23. Sunspot numbers for May 24-30 were 96, 86, 70, 83, 87, 73 and 78, with a mean of 81.9. The 10.7 cm flux was 115.5, 117.2, 110, 11…
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The average daily sunspot numbers declined seven points over the past week to 110.3, while the average daily solar flux dropped 3.3 points to 131. Sunspot numbers for May 17-23 were 114, 118, 110, 124, 120, 95 and 91, with a mean of 110.3. The 10.7 cm flux was 136.3, 132.2, 130.9, 130.8, 125.1, 121.3 and 117.2, with a mean of 127.7. The estimated planetary A indices were 6, 8, 5, 13, 7, 16 and …
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The average daily solar flux for the past week rose slightly, 116.2 to 119, but the average daily sunspot numbers declined more than 14 points (about 13 percent), to 92.6. Sunspot numbers for May 3-9 were 107, 101, 88, 104, 79, 90 and 79, with a mean of 92.6. The 10.7 cm flux was 114, 114, 116, 117.3, 121.7, 122.8 and 127.3, with a mean of 119. The estimated planetary A indices were 8, 4, 4, 5,…
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The average daily sunspot numbers declined 38 points to 106.7 this week, while the average daily solar flux declined nearly 18 points to 116.2. Sunspot numbers for April 26-May 2 were 117, 99, 118, 114, 104, 99 and 96, with a mean of 106.7. The 10.7 cm flux was 119.2, 117.9, 121.1, 116, 114.1, 109.9 and 115.5, with a mean of 116.2. The estimated planetary A indices were 17, 8, 5, 5, 3, 4 and 5,…
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As promised in the April 19th edition of The ARRL Letter, this week’s bulletin features a report on recent solar activity and solar cycle progression from Carl Luetzelschwab, K9LA.
Both the solar flux and sunspot numbers reached a short term low on April 8-11, but they are now rising again. For the past week — April 12-18 — the average daily sunspot numbers more than doubled, compared to the p…
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The bulletin appears a day early this week because ARRL Headquarters is closed for the Good Friday holiday.
Over the past week, the average daily sunspot number and solar flux values rose slightly, even though as the week progressed, each day had a lower number than the day before. The daily sunspot number began the week at a high of 100, but ended at 60. Likewise, the daily solar flux started a…
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Solar activity declined this week: The average daily sunspot numbers were off by more than 13 points to 75.1, while the average daily solar flux dropped over 32 points to 102.1. The solar flux dropped barely below 100, but rounded up to 100 as shown on the NOAA SEC site. The next short-term peak in solar flux is expected at the 135 level for April 3-6. The predicted solar flux for March 23-25 i…
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