The NW7US PROPAGATION
FORECAST
July, 2014
By Tomas Hood, NW7US
HF Propagation
Solar
activity is roughly the same this year as last year. This results in maximum usable frequencies staying
consistent with the same period, last year.
We expect good openings into most areas of the world through out the day
on 22, 19, and 16 meters. Through the
summer, expect a lot of propagation between north and south regions during the
daylight hours. Nineteen and 16 meters
will be the strong daytime bands, with 19 remaining a popular band throughout
the year. Reception of stations located
in tropical or equatorial areas may be possible well into the hours of
darkness. For distances between 800 to
several thousand miles, expect exceptionally strong signals. Multi-hop signals will be prevalent. Late afternoon and early evening broadcasts
will likely congest the band.
Twenty-five
and 22 meters will remain open from just before sunrise to a few hours past
sunset. From late afternoon to well into
darkness, expect these bands to offer worldwide coverage.
Thirty-one
meters is a year-round power band with outstanding domestic and international
paths, around the clock. During periods
of low geomagnetic activity this summer, this band may offer long distance DX
all through the night.
Forty-one
and 49 meters offer domestic propagation during daylight hours and somewhat
during the night. Geomagnetic storms
will wipe it out, however. The tropical
bands (60, 75, 90, and 120 meters) are not noticeably affected by the solar
flux, but are degraded during geomagnetic storminess. Through the summer, expect these bands to be
more challenging.
Overall,
daytime bands will open just before sunlight, and last a few hours after
dark. Look higher in frequency during
the day, as these frequencies will be less affected by any solar storms
occurring, and more broadcasters have transmissions in these upper bands.
VHF Conditions
July is one of the noticeably more active
months of the year for VHF propagation between stations from about 500 to about
3000 miles apart. Strong signals appear
on the lower VHF spectrum, and then quickly fade away. Experienced VHF DXers know this season as the
Sporadic-E season, and July is in the very peak of the yearly season that
begins in May, and ends by September.
Sporadic E propagation (abbreviated as Es
or Es) affects the highest frequencies of the shortwave spectrum, as
well as the lower to (sometimes) the mid-VHF spectrum. It occurs most frequently during late spring
and early summer. Sporadic E propagation
does not typically last very long, but the openings can be quite strong.
The
summertime Sporadic-E (Es) season for the Northern Hemisphere should
still be active through July. Usually
these Es openings are single-hop events with paths up to 1000 miles,
but July's Es events, like June's, can be double-hop. Look for HF openings on the higher
frequencies, as well as on low-VHF, throughout the day but especially in the
afternoon.
Of
course, with the increased geomagnetic storminess, there is a chance of Aurora
and the related Aurora-mode propagation.
Check out the latest conditions at my propagation page, < http://SunSpotWatch.com/ >.
I'd like to hear
from you
I welcome your
thoughts, questions, and experiences regarding this fascinating science of
propagation. You may e-mail me, write me
a letter, or catch me on the HF Amateur bands.
On Twitter, please follow @NW7US (and if you wish to have an hourly
automated update on space weather conditions and other radio propagation-related
updates, follow @hfradiospacewx). I invite you to
visit my online propagation resource at < http://SunSpotWatch.com/
>, where you can get the latest space data, forecasts, and more, all in an
organized manner. If
you are on FaceBook.com, check out < https://www.facebook.com/spacewx.hfradio
> and < https://www.facebook.com/NW7US
>.
Until next month,
73, Tomas, NW7US
PO Box 27654
Omaha, NE 68127
Web site: nw7us@nw7us.us
Twitter: @NW7US ( http://Twitter.com/NW7US )
Twitter: @hfradiospacewx ( http://Twitter.com/hfradiospacewx
)
