Space Weather Outlook #00-41 19 September 2000
SPACE WEATHER OUTLOOK #00-41
2000 September 19 at 02:58 p.m. MDT (2000 September 19 2058 UT)
**** SPACE WEATHER OUTLOOK ****
Summary For September 11-17 Space weather increased to strong (category 3) levels during the week. A G3 (strong)
geomagnetic storm occurred during 3:00 – 9:00 p.m. MDT on September 17 (17/2100 – 18/0300 UTC) due to a CME passage
at Earth. Category G3 geomagnetic storms may cause the following system effects: voltage corrections may be required and
false alarms may be triggered on some protection devices on electrical power grids; surface charging may occur on satellite
components, drag may increase on low-Earth-orbit satellites, and corrections may be needed for satellite orientation problems;
intermittent satellite navigation and low-frequency radio navigation problems may occur; high-frequency radio communication
may be intermittent; and aurora is visible as low as 50 degrees latitude. A category R2 (moderate) radio blackout occurred at
10:26 p.m. MDT on September 16 (17/0426 UTC) due to a large solar flare. Category R2 radio blackouts may result in the
following system effects on the sunlit portion of Earth: limited blackout of high-frequency radio communication resulting in
loss of radio contact for tens of minutes and degradation of low-frequency navigation signals for tens of minutes. A category
S2 (moderate) solar radiation storm occurred during September 12 – 15 due to a long-duration, moderate-sized solar flare.
Category S2 solar radiation storms may cause the following system effects: spacecraft may experience isolated single event
upsets, small effects on high-frequency radio communication through the polar regions, and navigation at the polar caps may be
affected.
Outlook For September 20-26 Space weather is expected to be at minor to moderate levels. A category G1 (minor) to G2
(moderate) geomagnetic storm is expected on September 20. An isolated category R2 (moderate) radio blackout is possible
sometime during the period. Otherwise, isolated category R1 (minor) radio blackouts are expected. A category S1 solar
radiation storm is also possible during the period.
