Solar activity remains robust. Yesterday, Thursday, November 14 the daily sunspot number rose to 234, a number not seen since the last blast of the second peak of the previous solar cycle, exactly a decade ago.
Way back on October 27 through November 1, 2003 the daily sunspot numbers were 238, 230, 330, 293, 266, and 277. That was it. Nothing as high as a sunspot number of 234 since then.
But the…
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Solar activity is increasing, suggesting that perhaps now in Fall 2013 we are in the midst of a second peak in cycle 24. We hope it sustains.
Sunspot numbers this week ran up all the way to 228, a level not seen in the past decade since October 27 through November 1, 2003 when the daily sunspot numbers were 238, 230, 330, 293, 266 and 277. Prior to that, on January 11, 2003 the daily sunspot num…
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NOAA’s Space Weather Prediction Center (SWPC) says solar activity is “high and intensifying,” and radio blackouts reaching the R3 levels have been observed over the past 24 hours. An R3 event can cause a wide-area blackout of HF radio communication and a loss of radio contact for about an hour on Earth’s sunlit side. Low-frequency navigation signals may be degraded for about an hour as well. A…
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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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Solar activity picked up over the seven days of our reporting week, October 3-9, and the outlook has improved somewhat. There now are no predictions for the solar flux dropping below 100 in the next 45 days. October 6 was the date of the last forecast predicting any flux values below 100. These predictions were for periods later in October and again in November.
Average daily sunspot numbers inc…
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Solar activity was very, very quiet over the past week. For the reporting period September 5-11, the average daily sunspot number was only 37.7. Average daily sunspot numbers as reported in this bulletin have not been nearly this low since June 6-12 of this year, when it was 39.6. The last time it was lower was June 21-27 of last year, when it was 26.3.
Australia’s IPS Radio and Space Services i…
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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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Solar activity picked up this week, with average daily sunspot numbers for August 15-21 up nearly 42 points (forty-nine percent) to 126.9, when compared to the previous seven days. Likewise, average daily solar flux increased from 111.7 to 126.3.
The latest prediction from USAF/NOAA has solar flux at 130, 125, 120, and 115 on August 23-26, 110 on August 27-29, 105 on August 30, 95 on August 31 t…
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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 activity remains quiet, but on May 16 the daily sunspot number reached 212. I had to keep searching further and further back in the records to find a higher sunspot number. One year, six months and one week earlier — November 9, 2011 — the sunspot number was almost that high, at 208. Going back seven years, 10 months and 12 days to July 4, 2005, it was 192. To find activity beating the …
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Solar activity made a healthy jump over the past week, with the average daily sunspot numbers up more than 30 points to 120.9, while the average daily solar flux increased more than 27 points to 136.5. The most active day for geomagnetic indices was May 1, when the planetary A index reached 21 and the high-latitude College A index (measured near Fairbanks, Alaska) was a whopping 57. That number…
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Solar activity was quiet this week: The average daily sunspot number declined nearly 23 points to 90.6, while the average daily solar flux values were down nearly 13 points to 109.1. The most active day was April 24, with a planetary A index of 19 and mid-latitude A index of 15. The average daily mid-latitude A index was the same this week as last, 4.9. Sunspot numbers for April 18-24 were 86, …
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While solar activity weakened this past week, geomagnetic conditions were stable. The geomagnetic storm predicted for last weekend did not happen, and both the planetary and mid-latitude A index only rose to 10 on April 14 in response to a glancing blow from a coronal mass ejection (CME). The average daily sunspot numbers declined nearly 25 points to 113.3, while the average daily solar flux wa…
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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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Solar activity was down this week, with the average daily sunspot number at 49.6, less than half last week’s figure. The average daily solar flux dropped 22 points to 97, and geomagnetic activity was quiet also. Sunspot numbers for March 21-27 were 60, 54, 56, 45, 56, 41 and 35, with a mean of 49.6. The 10.7 centimeter flux was 106.1, 100.9, 98.2, 96, 92.6, 92.4 and 93, with a mean of 97. The e…
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According to NASA, the current solar cycle — Solar Cycle 24 — should hit its “solar max” sometime in this year, but so far, solar activity has been relatively low. According to an article by NASA’s Dr Tony Phillips, this period of quiet has led some observers to wonder if forecasters missed the mark. But solar physicist Dean Pesnell of NASA’s Goddard Space Flight Center has a different explan…
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Solar activity continues at the low levels that we have seen in the past few weeks. The sunspot numbers have been remarkably consistent, with the average daily numbers for the weeks since January 17 at 56.4, 55.7, 50.7 and finally 51.3 for this past week. As you can see, the average daily sunspot number rose less than 1 point from the previous week to the past week, while the average daily sola…
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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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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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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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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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Solar activity jumped way up this week, with the average daily sunspot numbers increasing by nearly 92 points to 118.1, while the average daily solar flux rose to 138.5 from 92.8 the week before. One new sunspot group appeared on June 29, another on July 1 and two more on July 4. Sunspot numbers for June 28-July 4 were 73, 97, 90, 137, 165, 136 and 129, with a mean of 118.1. The 10.7 cm flux wa…
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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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Solar activity revived over the past week, with a big increase in sunspot numbers. On Friday, April 20, the daily sunspot number reached 162; four days later on April 24, the number reached 169. This level of activity has not been seen since last fall, when the daily sunspot number reached 173 on September 16, 184 on October 21 and 208 on November 9.
The average daily sunspot numbers more than d…
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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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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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