venerdì 17 gennaio 2020

The K7RA Solar Update

Cycle 25 sunspots persisted for the first two days (January 9-10) of this reporting week, January 9-15, with daily sunspot numbers of 14 and 11. That brought the weekly average daily sunspot number from 8.4 last week to 3.6. Average daily solar flux edged up from 71.8 to 72.5.

Average daily planetary A index declined from 6.3 to 5.6, and average middle latitude A index went from 5.3 to 3.7.

Predicted solar flux for the next 45 days is 72 and 71 on January 17-18, 70 on January 19 through February 7, 72 on February 8-22, and 70 on February 23 through March 1.

Predicted planetary A index is 5 on January 17-18, 8 on January 19-20, 5 on January 21-31, 8 on February 1-2, 5 on February 3, 10 on February 4-6, 5 on February 7-9, 10 on February 10-11, 5 on February 12-22, 8 on February 23-24, 5 on February 25-27, 8 on February 28-29 and 5 on March 1.

Geomagnetic activity forecast for the period January 17 until February 12, 2020 by F.K. Janda, OK1HH.

Geomagnetic field will be
Quiet on: January 18, 29-30, February 6-9
Quiet to unsettled on: January 19-21, 24-28, February 1, 4-5, 10-11
Quiet to active on: (January 17, 22-23, 31, February 2-3, 12)
No unsettled to active periods predicted.
No active to disturbed periods predicted.

Solar wind will intensify on: January (17, 22-24,) February 2 (-5)

Parenthesis means lower probability of activity enhancement.
The predictability of changes is lower again

N8II wrote, concerning his report in last week's bulletin, "I forgot to mention that the January 9 contact with LA5MIA was on 20-meter SSB vs the Es contacts on 10 meters."

Also, from Jon Jones, N0JK, “Jeff, N8II, mentioned conditions on 160 meters in the Stew Perry contest ‘January 28-29.’ I am sure he meant December 28-29, 2019. ( His 10-meter Es reports correlate with the 6-meter Es occurring. I’m hoping for more winter Es.”

Jon Jones, N0JK noted in an email titled "more corrections": "I made some boo-boos, too. K1SIX is in grid FN43. KN4NN is in grid EM70."

N0JK shared late on January 16: "Six-meter Es seemed to vanish after the strong openings the second week of January. A brief Es opening between Florida and Ohio was noted January 13 around 1800z by KD4ESV in EL87, KW4BY in EL96, and others. AA5B operated MSK144 meteor scatter January 15 from rare grid DM63. The January VHF contest this weekend."

It seems we have crossed a threshold. Though solar activity remains low, recent history shows no Cycle 24 sunspots, only Cycle 25 activity. I remain optimistic. Also, with historically low geomagnetic activity, this is a great time to enjoy 160 meters.

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Sunspot numbers for January 9 through 15, 2020 were 14, 11, 0, 0, 0, 0, and 0, with a mean of 3.6. 10.7 cm flux was 74.4, 72.8, 73.5, 71.9, 71.5, 71.9, and 71.2, with a mean of 72.5. Estimated planetary A indices were 12, 7, 6, 4, 3, 3, and 4, with a mean of 5.6. Middle latitude A index was 8, 6, 4, 2, 2, 2, and 2, with a mean of 3.7. (www.arrl)