ZCZC AP26
QST de W1AW
Propagation Forecast Bulletin 26 ARLP026
From Tad Cook, K7RA
Seattle, WA June 25, 2004
To all radio amateurs
SB PROP ARL ARLP026
ARLP026 Propagation de K7RA
This is Field Day weekend! Conditions don't look bad, although there is the chance of geomagnetic conditions becoming unsettled.
This week the sunspot numbers have improved, while geomagnetic conditions were quiet, which is a great combination. Average daily sunspot numbers rose more than 50 points from last week to 116. Average daily solar flux was up almost 18 points to 113.7. Sunspot numbers were the highest on June 20 and 21, Sunday and Monday, and both the planetary and mid-latitude A indices were very low--in the lower single digits. Check out the Space Environment Center Web site, and you can see the K index at one and zero at all locations for several days.
Sunspot groups 634 and 635 provided most of the activity. Today they are moving out of view. As a result, predicted sunspot and solar flux numbers are a bit lower, with the solar flux forecast for Friday through Monday, June 25-28, at 100, 95, 95 and 90. Predicted planetary A index for the same four days is currently at 12, 12, 15 and 15. This is due to weak, high-speed solar wind from a recurrent coronal hole coming into view.
K7RA will do some Field Day operating in Class C--stations in vehicles capable of operating while in motion and normally operated in this manner. I'll probably be on 15 and 20 meters, both phone and CW, and 10 meters if it shows any life, and the operating style will be casual.
One of the fun things about the Field Day operating activity is that the paperwork is very easy. When submitting a contest entry, you only turn in a list of stations worked, sorted alphanumerically and divided by band and mode, along with a summary sheet. Unlike the ARRL Sweepstakes or DX contests, you will never lose points for incorrectly copying the exchange from the other station or the time of the contact, because you don't even report it. Additionally, there are no multipliers for states or sections worked or for DX. I'll probably just sort my call sign lists on a laptop with a simple text editor or word processor while operating, then e-mail in the results.
For Field Day 2004, 20 meters will be your best band, and possibly 15 as well. Ten meters may be good for some sporadic E skip. Forty and 80 meters should be good after dark. Run some numbers using a sunspot count of 100 or 105 and a K index of 2 or 3 using the free W6ELprop software to get an idea of where openings might occur.
Sunspot numbers for June 17 through 23 were 106, 118, 90, 142, 139, 113 and 104, with a mean of 116. The 10.7 cm flux was 111.3, 107.8, 112.7, 119.1, 115.8, 116.7 and 112.5, with a mean of 113.7. Estimated planetary A indices were 7, 8, 5, 3, 4, 4 and 5, with a mean of 5.1. Estimated mid-latitude A indices were 7, 10, 4, 3, 3, 1 and 2, with a mean of 4.3.