Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 12 April 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast

SDF Number 102 Issued at 2200Z on 12 Apr 2015

IA.  Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M1 event observed at 12/0950Z from Region 2321 (N13E54). There are currently 4 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is likely to be moderate with a slight chance for an X-class flare on days one, two, and three (13 Apr, 14 Apr, 15 Apr).

IIA.  Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field has been at quiet levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 395 km/s at 11/2252Z. Total IMF reached 6 nT at 12/1339Z. The maximum southward component of Bz reached -2 nT at 11/2116Z.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on days one, two, and three (13 Apr, 14 Apr, 15 Apr).

III.  Event probabilities 13 Apr-15 Apr

Class M    55/55/55

Class X    20/20/20

Proton     05/05/05

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           12 Apr 134

Predicted   13 Apr-15 Apr 135/135/130

90 Day Mean        12 Apr 128

V.  Geomagnetic A Indices

Observed Afr/Ap 11 Apr  014/021

Estimated Afr/Ap 12 Apr  004/005

Predicted Afr/Ap 13 Apr-15 Apr  005/005-005/005-005/005

VI.  Geomagnetic Activity Probabilities 13 Apr-15 Apr

A.  Middle Latitudes

Active                05/05/05

Minor Storm           01/01/01

Major-severe storm    01/01/01

B.  High Latitudes

Active                15/15/15

Minor Storm           20/20/20

Major-severe storm    10/10/10