Solar activity report

Viewing archive of Wednesday, 18 May 2016

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 2016 May 18 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 139 Issued at 2200Z on 18 May 2016

IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z

Solar activity has been at very low levels for the past 24 hours. There are currently 2 numbered sunspot regions on the disk.

IB. Solar Activity Forecast

Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (19 May, 20 May, 21 May).

IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z

The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 566 km/s at 17/2109Z. Total IMF reached 8 nT at 18/1054Z. The maximum southward component of Bz reached -6 nT at 18/1014Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 987 pfu.

IIB. Geophysical Activity Forecast

The geomagnetic field is expected to be at quiet to active levels on days one and three (19 May, 21 May) and unsettled to minor storm levels on day two (20 May).

III. Event Probabilities 19 May to 21 May

Class M	01%	01%	01%
Class X	01%	01%	01%
Proton	01%	01%	01%
PCAF	green

IV. Penticton 10.7 cm Flux

  Observed       18 May 102
  Predicted   19 May-21 May 103/105/105
  90 Day Mean        18 May 093

V. Geomagnetic A Indices

  Observed Afr/Ap 17 May  014/012
  Estimated     Afr/Ap 18 May  008/008
  Predicted    Afr/Ap 19 May-21 May  014/016-017/022-011/016

VI. Geomagnetic Activity Probabilities 19 May to 21 May

A. Middle Latitudes
Active	35%	35%	35%
Minor storm	25%	30%	15%
Major-severe storm	05%	10%	05%

B. High Latitudes
Active	10%	10%	10%
Minor storm	25%	20%	25%
Major-severe storm	55%	65%	50%

All times in UTC

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G2 - Moderate geomagnetic storm

Observed Kp: 6
Threshold reached: 20:16 UTC

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

Rovaniemi, Sodankylä, Utsjoki
Reykjavik
Kirkenes, Tromsø
Murmansk
Kiruna, Luleå

The solar wind speed is currently moderately high (551.4 km/sec.)

The strength of the interplanetary magnetic field is moderate (18.36nT), the direction is North (5.05nT).

The Disturbance Storm Time index predicts moderate storm conditions right now (-67nT)

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