Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 1 April 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast

SDF Number 91 Issued at 2200Z on 01 Apr 2015

IA.  Analysis of Solar Active Regions and Activity from 31/2100Z to 01/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 5 numbered sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be low with a chance for M-class flares on days one, two, and three (02 Apr, 03 Apr, 04 Apr).

IIA.  Geophysical Activity Summary 31/2100Z to 01/2100Z: The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 450 km/s at 01/2057Z. Total IMF reached 14 nT at 01/1953Z. The maximum southward component of Bz reached -8 nT at 01/1516Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 461 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (02 Apr), unsettled to active levels on day two (03 Apr) and unsettled levels on day three (04 Apr).

III.  Event probabilities 02 Apr-04 Apr

Class M    25/25/25

Class X    05/05/05

Proton     01/01/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           01 Apr 124

Predicted   02 Apr-04 Apr 130/140/125

90 Day Mean        01 Apr 132

V.  Geomagnetic A Indices

Observed Afr/Ap 31 Mar  007/011

Estimated Afr/Ap 01 Apr  008/009

Predicted Afr/Ap 02 Apr-04 Apr  010/012-014/020-012/015

VI.  Geomagnetic Activity Probabilities 02 Apr-04 Apr

A.  Middle Latitudes

Active                25/35/30

Minor Storm           05/10/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                15/20/15

Minor Storm           20/25/30

Major-severe storm    10/25/35