STD - CME-Prognose - UPDATE

[Ulrich Rieth]

http://www.spacew.com/cme/index.html

Event #35b - 24 November 2002
Issued: 12:00 UTC, 25 November 2002
Updated: 04:50 UTC, 26 November 2002

SOURCE EVENT

Hyder Flare near N25 E40 at 20:29 UTC on 24 November
Type II: 800 km/sec
Estimated LASCO-derived Plane of Sky Velocity: near 1042 km/sec (N)

ESTIMATED TIME OF ARRIVAL OF SHOCK AT EARTH

Revised Estimated Impact Window: 21:00 UTC on 26 November to 23:00 UTC on 27 November
Preferred Predicted Impact Time: 08:30 UTC, 27 November 2002
Estimated Shock Strength (0: Weakest, 9=Strongest): 5

Predicted Behavior of IMF at Shock Impact

At Shock Impact, the Interplanetary Magnetic Field is predicted to initially turn:
SOUTHWARD

EVENT #35b NOTES:

A classic disappearing filament related parallel ribbon hyder flare in the northeast quadrant resulted in a full halo CME. Although the shock front itself is not expected to be particularly energetic, there is a chance the Earth may intersect some regions of moderately high strength IMF - interplanetary magnetic fields (perhaps 20 to 40 nT). If a southward turning of the IMF is realized, periods of moderate to strong geomagnetic and auroral storming will be possible.

ADDENDUM: Additional data analysis and current observations suggest the observed plane of sky velocity of the CME is probably closer to the true velocity than the observed Type II shock velocity. The estimated impact time has been adjusted above accordingly.

These predictions may be based on preliminary data and may be revised without warning. The predictions should not be used as a definitive indication of CME impact times or strengths and may frequently be in error. The proprietary methods used to estimate shock impact times are under continual development. Caution is advised.