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QST de W1AW
> >Propagation Forecast Bulletin 43  ARLP043
> > >From Tad Cook, K7VVV
> >Seattle, WA  October 19, 2001
> >To all radio amateurs
> >
> >SB PROP ARL ARLP043
> >ARLP043 Propagation de K7VVV
> >
> >Sunspot numbers and solar flux values rose this week. Average daily
> >sunspots were up nearly 18 points, and average solar flux rose
> >almost 40 points. Solar flux was mostly in the 170s for a couple of
> >weeks, until this week when it went above 190, and then 200.
> >
> >Solar flux for the next few days should continue this rise, with
> >values of 235, 240, 245 and 250 predicted for Friday through Monday.
> >Unless new sunspots emerge, the solar flux is expected to decline
> >below 200 by the end of this month.
> >
> >You can see a difference in sunspots corresponding to the sudden
> >change in solar flux. Look at a photo for October 13, when the flux
> >was still below 180, at web site
> >spaceweather.com/images2001/13oct01/midi512_blank.gif .
> >
> >Then take a look at an image from another day, at
> >spaceweather.com/images2001/18oct01/midi512_blank.gif , which
> >shows the October 18 photo when the flux was 228.7. Notice how the
> >big sunspot group that was off to the side is now in the middle,
> >aimed more toward earth.
> >
> >Thursday and Friday, October 11 and 12, had unsettled to active
> >geomagnetic conditions, but geo-indices have been quiet since. This
> >was expected to continue, with A indices below 10, until today at
> >0105z when a large solar flare erupted from sunspot region 9661, the
> >big spot seen in the center of the solar disk in the October 18
> >photo referenced above. The energy from this flare caused a radio
> >blackout across Asia and Australia, and is expected to fully affect
> >earth on Sunday, October 21.
> >
> >Sunspot numbers for October 11 through 17 were 174, 179, 166, 178,
> >176, 168 and 171 with a mean of 173.1. 10.7 cm flux was 174.8,
> >179.2, 179.5, 191.9, 192.9, 207.2 and 217.4, with a mean of 191.8,
> >and estimated planetary A indices were 17, 27, 10, 9, 11, 8 and 4
> >with a mean of 12.3.
> >


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