SPACE WEATHER ADVISORY BULLETIN

Official Space Weather Advisory issued by NOAA Space Environment Center
Boulder, Colorado, USA

SPACE WEATHER ADVISORY BULLETIN #05- 4
2005 July 27 at 9:36 a.m. MDT (2005 July 27 1536 UTC)

**** SOLAR ACTIVITY INCREASING ****

A minor radio blackout (R1) occurred today at 27/0502 UTC (26/2302 MST).
This activity indicates the likely return of old NOAA active sunspot
region 786 to the front side of the Sun. During the last rotation
across the Sun (01 - 14 July), this region produced moderate to strong
(R2 - R3) radio blackouts, and minor to moderate geomagnetic (G1 - G2)
and solar radiation storms (S1 - S2). Solar imagery over the past few
days indicated several strong eruptions from behind the Sun, which were
assumed to be associated with this region. Further major eruptions are
anticipated from this region.

Agencies impacted by solar flare radio blackouts, geomagnetic storms,
and solar radiation storms should continue to closely monitor the space
environment over the next two weeks.

Data used to provide space weather services are contributed by NOAA,
USAF, NASA, NSF, USGS, the International Space Environment Services
and other observatories, universities, and institutions. More
information is available at SEC's Web site http://sec.noaa.gov