NOAA SEC Space Weather Outlook #01-48 — 27 Nov 2001

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

SPACE WEATHER OUTLOOK #01- 48

2001 November 27 at 02:12 p.m. MST (2001 November 27 2112 UT)

**** SPACE WEATHER OUTLOOK ****

Summary For November 19-25

Space weather increased to severe levels due to geomagnetic and solar
radiation storms. A category S1 (minor) solar radiation storm was in
progress as the period began, then ended on November 20. A category S4
(severe) solar radiation storm began on November 22 and continued
through the end of the period. This storm was caused by a major solar
flare that reached its peak at 4:30 p.m. MST on November 22 (2001
November 22 2330 UT). This flare also caused a category R2 (moderate)
radio blackout as well as an Earth-directed coronal mass ejection
(CME). This CME reached Earth on November 24 and caused a category G4
(severe) geomagnetic storm. A category R3 (strong) radio blackout
occurred at 2:51 a.m. MST on November 25 (2001 November 25 0951 UT) due
to a major solar flare. For a list of adverse system effects related to
space weather storms, please refer to the NOAA Space Weather Scales.

Outlook For November 28-December 4

Space weather is expected to decrease to mostly minor levels. Isolated
category R1 (minor) radio blackouts are expected. However, there will
also be a slight chance for an isolated category R2 (moderate) radio
blackout sometime during the period. No geomagnetic or solar radiation
storms are expected.

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 or
(303) 497-5127. The NOAA Public Affairs contact is Barbara McGehan
at bmcgehan@boulder.noaa.gov or (303) 497-6288.