ARRL

ARRL Propagation Bulletin ARLP025 (2001)

SB PROP @ ARL $ARLP025
ARLP025 Propagation de K7VVV

ZCZC AP25
QST de W1AW  
Propagation Forecast Bulletin 25  ARLP025
From Tad Cook, K7VVV
Seattle, WA  June 15, 2001
To all radio amateurs 

SB PROP ARL ARLP025
ARLP025 Propagation de K7VVV

Sunspot numbers and solar flux rose this week.  Average daily
sunspot numbers were up nearly 75 points and average daily solar
flux was up over 26 points.  The daily sunspot number peaked on
Saturday at 250, dipped, and rose again to 249 on Monday.  Daily
sunspot numbers have not been that high since the big jump in
activity around the end of March.

Disturbed days were Saturday and Sunday, when planetary A indices
were 20, and the planetary K index was five over two 3-hour
reporting periods.  The high latitude College A index was 28 and 31
over the same two days.

Solar flux rose to 194.7 on Thursday, but is expected to dip below
170 this weekend.  Predicted planetary A index is 10 for Friday and
Saturday and 15 for Sunday.

On Wednesday a strong solar flare was released from sunspot group
9502.  It propelled a coronal mass ejection from the sun's eastern
limb, pointed away from earth.  The sun is currently covered with
small sunspots, and there is a possibility of more flare activity on
Friday.

Here are some path projections for the All Asia contest this
weekend.  These are all based on propagation toward Japan.

From the center of the continental U.S., 80 meters 1030-1100 UTC, 40
meters 0930-1200 UTC, 20 meters 0700-1430 UTC, 15 meters best around
0330-0500 UTC, worst 0730-1200 UTC, 10 meters possibly 1500-1700 and
2100-2200 UTC.

From Atlanta, 40 meters 1000-1100 UTC, 20 meters 0730-1300 UTC, 15
meters best 0330-0600 UTC and worst around 0200 UTC, 0730-1000 UTC
and 1730-1800 UTC, 10 meters possibly open 0300-0430 and 1300-2030
UTC.

From Boston, 20 meters 0730-1230 UTC (best from 0900-1030 UTC), 15
meters best after 1200 UTC, worst 0300-1130 UTC.

From Cleveland, 20 meters 0700-1330 UTC (best from 0900-1130 UTC),
15 meters best after 1230 UTC, worst 0430-1200 UTC, 10 meters
possibly 1230-1700 or 1800-2000 UTC.

From Chicago, 40 meters possibly 1000-1100 UTC, 20 meters 0700-1430
UTC (best 0830-1200 UTC), 15 meters best after 1230 UTC, worst 0500-
1200 UTC, 10 meters possibly 1300-1700 or 1800-2030 UTC.

From Dallas, 80 meters 1030-1100 UTC, 40 meters 0930-1200 UTC, 20
meters 0700-1430 UTC, 15 meters open 24 hours, best 0330-0500 UTC,
worst 0800-1130 and 1330-1830 UTC, 10 meters possibly 0330-0500 or
1330-2100 or 2200-0100 UTC.

From Southern California (San Diego), 80 meters 0930-1230 UTC, 40
meters 0930-1330 UTC, 20 meters 0630-1600 UTC, 15 meters open all
hours, best 0500-0800 UTC, worst 1500-1530 UTC, 10 meters possibly
0500-0800, 1500-1630, and 1930-0230 UTC.

From San Francisco, 80 meters 1000-1300 UTC, 40 meters 0900-1400
UTC, 20 meters 0630-1630 UTC, 15 meters open all hours, best 0530-
0830 UTC, worst 1100-1230 UTC, 10 meters possibly 1530-1600 UTC or
2000-2300 UTC.

From Seattle, 80 meters 1030-1230 UTC, 40 meters 0930-1330 UTC, 20
meters 0630-1700 UTC, 15 meters possibly 1300-1900 UTC or 0500-0930
UTC.

From Omaha, 40 meters 1000-1130 UTC, 20 meters 0700-1500 UTC, 15
meters open all hours, best 0400-0700 UTC and 1500-1800 UTC, worst
0730-1430 UTC.

From Salt Lake City, 80 meters 1000-1200 UTC, 40 meters 0930-1300
UTC, 20 meters 0630-1630 UTC, 15 meters open all hours, best around
0500 UTC, weakest 0830-1430 UTC.

Sunspot numbers for June 7 through 13 were 163, 179, 250, 217, 249,
193 and 221 with a mean of 210.3. 10.7 cm flux was 164.8, 180.2,
177, 163, 162.4, 166.4 and 181.4, with a mean of 170.7, and
estimated planetary A indices were 12, 8, 20, 20, 10, 7 and 14 with
a mean of 13.
NNNN
/EX