Viewing archive of Wednesday, 17 September 2008

Solar activity report

Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2008 Sep 17 2201 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 261 Issued at 2200Z on 17 Sep 2008

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

Solar activity was very low. No flares were observed during the past 24 hours. The visible disk remained spotless.
IB. Solar Activity Forecast
Solar activity is expected to be very low.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was predominately quiet. An isolated unsettled period was observed between 17/0300-0600Z. Solar wind speed measured at the ACE spacecraft showed a gradual decrease from approximately 530 km/s to 410 km/s during the forecast period. 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 predominately quiet with isolated unsettled conditions for the next three days (18-20 September).
III. Event Probabilities 18 Sep to 20 Sep
Class M01%01%01%
Class X01%01%01%
Proton01%01%01%
PCAFGreen
IV. Penticton 10.7 cm Flux
  Observed       17 Sep 067
  Predicted   18 Sep-20 Sep  066/066/066
  90 Day Mean        17 Sep 066
V. Geomagnetic A Indices
  Observed Afr/Ap 16 Sep  007/009
  Estimated     Afr/Ap 17 Sep  005/005
  Predicted    Afr/Ap 18 Sep-20 Sep  005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 18 Sep to 20 Sep
A. Middle Latitudes
Active10%10%10%
Minor storm01%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Active10%10%10%
Minor storm01%01%01%
Major-severe storm01%01%01%

All times in UTC

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Current data suggests there is a moderate possibility for aurora to appear at the following high latitude regions in the near future

Nuuk
Reykjavik

Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future

Tórshavn
Kuopio
Trondheim
Luleå, Sundsvall, Umeå
The solar wind speed is currently moderately high (508 km/sec.)
The maximum X-ray flux of the past two hours is:
C6.38
A southern hemisphere coronal hole was detected in an earth-facing position on Tuesday, 8 April 2025

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