ARRL

ARRL Propagation Bulletin ARLP029 (1999)

SB PROP @ ARL $ARLP029
ARLP029 Propagation de KH6BZF

ZCZC AP29
QST de W1AW  
Propagation Forecast Bulletin 29  ARLP029
From Lee R. Wical, KH6BZF
Kane'Ohe, HI July 16, 1999
To all radio amateurs 

SB PROP ARL ARLP029
ARLP029 Propagation de KH6BZF

Average solar flux and sunspot numbers were down this week as
compared to last week. But this is not surprising considering last
week's higher solar numbers.  The average sunspot number dropped and
average solar flux units were down as well.

The forecast for the next three days, Friday through Sunday, is a
solar flux of 130, 140 and possibly 145 and planetary A index of
five for all three days.  Beyond this weekend look for possible
increasing solar flux levels. Solar flux levels are expected to
continue to rise until a cyclic 27.5-day peak centered on/about 25th
July around the 200+ level. One forecast earlier this week from the
NOAA Space Environment Service Center in Boulder, CO, has solar flux
peaking around 200 from July 22 through 27, but a later more liberal
projection suggests a peak above 200+ as mentioned above.

Current summer conditions in North America affect the 160 and 80
meter bands.  They are noisy because of seasonal atmospherics in the
Northern hemisphere due to transcontinental thunderstorms. Check
your local TV and national cable weather channels for additional up
to the minute data. However, QRM/QRN static levels from these storms
can be a precursor to low band beacons. Meanwhile, 20 meters is open
late into the evening and toward sunrise on the eastern end of the
east-west DX path. Conditions on 10 and 12 meters will tend to get
better for long distance communications as the days grow shorter and
we progress toward the fall equinox on September 22, 1999.

West coast stations again have been reporting VHF signals from
KH6HME's 50/144/432MHz beacons in Hawaii via tropospheric ducting as
recent as July 15.  Check the KH6FOO web page at
http://hiloweb.com/kh6foo/duct.html

KH6FOO's web site reports on propagation modes, frequencies, etc.
Click on the Post Ducting Report button to see current data therein.
VHF West coasters report KH6HME's beacons being heard as early as
July 10th.  Other 6 meter North America transcontinental reports
have been received as well. June's E openings were exciting to old
timers and newly licensed Amateurs alike.

Sunspot numbers for July 8th through 15th were, 143, 170, 174, 202,
199, 188, 120 and 109 with a mean of 163.1, down from last week's
mean of 204. The 10.7 cm flux levels for the same period were, 149,
151, 156, 153, 154, 144, 130 and 130 with a mean level of 145.8,
down from last week's mean level of 180.8, and estimated planetary A
indices were 08, 06, 05, 06, 14, 06, 06 and 10 with a mean average
8.87, a decline from last week's average of 10.

The DX path projections for this week are from Jacobs Field in
Cleveland, Ohio:

To Europe, 17 meters 1930-0200z, 20 meters 2030-0700z, 30 meters
2200-0600z, 20 meters great at all hours, but peaking 0200-0300z.
10/12/15 meters mostly NIL and none.

To Southern Africa, 20 meters weakly from 0600-0730z. 17 meters
poorly 00830-1100z, 30 meters 0130-0400z, 40 meters 0000-0530z.
Again, 10/12 meters NIL and none.

To the Caribbean, 80 meters 0000-1000z, 40 meters 2239-1130z, 30
meters 0230-1030z, 20 meters 2230-1130z, 17 meters 1930-0500z, 15
meters weakly 1900-0400z, 10 meters NIL and none.

To the center of the continental USA, 80/40 meters all day and
night, 30 meters about the same, 20 meters all hours, best sunset to
sunrise, 17 meters possibly 1200-0200z. Some 10/12 short skip.

To the East coast all day on 40 meters and 80 meters about the same.
Other bands an occasional short skip during the daylight paths.

To the West coast 80 meters between 0200-1100z 40 meters 0000-1230z,
20 meters possible weak paths between 1830-0430z, 17/15/12 and 10
meters best go fly fishing instead. But some electronic fishing
might be had.

To South America, 80 meters 0000-0930z, 40 meters 2300-1030z, 30
meters 2000-1000z, 20 meters 1900-1300z, 17 meters 2230- 1330z, 15
meters 2100-0230z and 0530-0630z, 10/12 meters again NIL and none.

To Australia, 80 meters 0830-1030z, 40 meters 0730-1130z, 30 meters
0830-1500z, 20 meters 0600-1400z, 17 meters 0500-1100 z, 15 meters
0230-0400z and 12/10 meters NIL.

To Japan, 80 meters NIL, 40 meters 0900-1100z, 30 meters 0430-0930z,
20 meters 0700-1400z and 15/12/10 meters NIL. Good hunting.

The current forecast is for low to moderate levels of solar activity
with some occasional isolated flares that may occur. There may be a
slight chance of an M-class flare to occur during the next week.
However, the Geomagnetic Field is expected to be at quiet to
unsettled levels with a coronal mass ejection expected at any time.
Flux levels are expected to rise this coming week. High to above
normal conditions are expected. But one can ever tell about two
things. Our Sun, our nearest star, and the stockmarket. There is no
correlation whatsoever between the two, except the unexpected.

The last solar eclipse of the millennium occurs next month on August
11.  A day later, on the 12th of August, the Perseids Meteor show is
to peak. The last meteor shower of the millennium will be the
Leonids Meteor Shower occurring on the nights of the 16, 17 and 18th
of November when the Moon sets just before the prime viewing hours.

A Note to all:  Thanks to K7VVV for allowing me to substitute for
him as business called him away from his propagation ''cat bird seat''
duties on short notice.  Aloha.
NNNN
/EX