Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 14 April 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast

SDF Number 104 Issued at 2200Z on 14 Apr 2015

IA.  Analysis of Solar Active Regions and Activity from 13/2100Z to 14/2100Z: Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 13/2323Z from Region 2320 (S14W78). There are currently 6 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 (15 Apr, 16 Apr, 17 Apr).

IIA.  Geophysical Activity Summary 13/2100Z to 14/2100Z: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 358 km/s at 14/1432Z. Total IMF reached 11 nT at 14/1523Z. The maximum southward component of Bz reached -11 nT at 14/1523Z.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to minor storm levels on day one (15 Apr), quiet to minor storm levels on day two (16 Apr) and quiet levels on day three (17 Apr).

III.  Event probabilities 15 Apr-17 Apr

Class M    55/55/55

Class X    20/20/20

Proton     05/05/05

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           14 Apr 147

Predicted   15 Apr-17 Apr 150/155/155

90 Day Mean        14 Apr 128

V.  Geomagnetic A Indices

Observed Afr/Ap 13 Apr  012/008

Estimated Afr/Ap 14 Apr  004/005

Predicted Afr/Ap 15 Apr-17 Apr  015/020-012/015-007/008

VI.  Geomagnetic Activity Probabilities 15 Apr-17 Apr

A.  Middle Latitudes

Active                35/35/20

Minor Storm           15/15/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                10/15/15

Minor Storm           30/30/20

Major-severe storm    50/45/25