Joint USAF/NOAA Report of Solar and Geophysical Activity 18 Oct 2006

Product: Report of Solar-Geophysical Activity
Issued: 2006 Oct 18 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 291 Issued at 2200Z on 18 Oct 2006

IA. Analysis of Solar Active Regions and Activity from 17/2100Z to 18/2100Z: Solar activity continues at very low levels. There are no sunspots on the visible disk.

IB. Solar Activity Forecast: Solar activity is expected to continue at very low levels.

IIA. Geophysical Activity Summary 17/2100Z to 18/2100Z: The geomagnetic field was quiet. Solar wind speed declined to below 320 km/s. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet with isolated unsettled periods on 19 October. A recurrent coronal hole high speed stream is expected to rotate into a geoeffective position on 20 October, and produce active to minor storm periods on both the 20th and 21st.

III. Event Probabilities 19 Oct-21 Oct

• Class M 01/01/01
• Class X 01/01/01
• Proton 01/01/01
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 18 Oct 070
• Predicted 19 Oct-21 Oct 070/070/070
• 90 Day Mean 18 Oct 077

V. Geomagnetic A Indices

• Observed Afr/Ap 17 Oct 002/002
• Estimated Afr/Ap 18 Oct 002/005
• Predicted Afr/Ap 19 Oct-21 Oct 005/008-015/020-010/015

VI. Geomagnetic Activity Probabilities 19 Oct-21 Oct A. Middle Latitudes

• Active 15/40/35
• Minor storm 01/20/15
• Major-severe storm 01/05/05

B. High Latitudes

• Active 20/50/45
• Minor storm 05/30/25
• Major-severe storm 01/10/05