Report of Solar-Geophysical Activity
Issued: 2006 Dec 15 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA, # Space Environment Center
and the U.S. Air Force.
Joint USAF/NOAA Report of Solar and Geophysical Activity SDF Number 349 Issued
at 2200Z on 15 Dec 2006
IA. Analysis of Solar Active Regions and Activity from 14/2100Z to 15/2100Z:
Solar activity was high. Region 930 (S06W59) produced an X1.5/2B solar flare
with a 510 sfu 10 cm radio burst at 14/2215Z. Type II (1277 km/s) and Type IV
radio sweeps were associated with this event. The flare was accompanied by a
frontside, asymmetrical, full halo CME with an estimated plane-of-sky speed of
900 km/s. Ejecta of this CME seems to be predominately from the southwest sector
of the halo.
IB. Solar Activity Forecast: Solar activity is expected to be moderate to high.
Isolated X-class flares from Region 930 remain a possibility.
IIA. Geophysical Activity Summary 14/2100Z to 15/2100Z:
The geomagnetic field reached severe storm levels. A 100 MeV proton event
commenced 14/2255Z, reached a 2.3 pfu maximum at 15/0015Z and ended 15/0325Z.
The greater than 10 MeV proton event that commenced 13/0310Z, reached a 698 pfu
maximum at 13/0925Z and ended at 15/1620Z. The greater than 2 MeV electrons
reached high levels today. Solar wind speed has decreased to 600 km/s.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to reach
major to severe storm levels. A glancing blow from the CME late in the day of 14
December is expected to impact the geomagnetic field by mid to late UTC on day
one of the forecast period (December 16). Minor to major storm levels are
expected to continue into December 17. The disturbance is expected to abate to
quiet to unsettled conditions for the final day of the forecast period (December
18).
III. Event Probabilities 16 Dec-18 Dec
Class M 65/65/65
Class X 35/35/35
Proton 01/01/01
PCAF yellow
IV. Penticton 10.7 cm Flux
Observed 15 Dec 087
Predicted 16 Dec-18 Dec 090/090/090
90 Day Mean 15 Dec 081
V. Geomagnetic A Indices
Observed Afr/Ap 14 Dec 030/063
Estimated Afr/Ap 15 Dec 060/100
Predicted Afr/Ap 16 Dec-18 Dec 040/045-045/070-008/010 VI. Geomagnetic Activity
Probabilities 16 Dec-18 Dec A. Middle Latitudes
Active 10/10/30
Minor storm 35/35/15
Major-severe storm 50/50/05
B. High Latitudes
Active 05/05/30
Minor storm 30/30/20
Major-severe storm 60/60/10
ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Threshold Reached: 2006 Dec 16 0500 UTC
Station: GOES12
Observed Yesterday: Yes
Yesterday Maximum 2MeV Flux: 45700 pfu
WARNING: Geomagnetic Sudden Impulse expected
Valid From: 2006 Dec 16 1745 UTC Valid To: 2006 Dec 16 1830 UTC IP Shock
Passage Observed: 2006 Dec 16 1722 UTC