Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 16 May 2015

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast

SDF Number 136 Issued at 2200Z on 16 May 2015

IA.  Analysis of Solar Active Regions and Activity from 15/2100Z to

16/2100Z: 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

15/2329Z from Region 2339 (N12W59). There are currently 7 numbered

sunspot regions on the disk.

IB.  Solar Activity Forecast: Solar activity is expected to be low with

a slight chance for an M-class flare on days one and two (17 May, 18

May) and expected to be very low with a chance for a C-class flares on

day three (19 May).

IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z: 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 518 km/s at

16/0033Z. Electrons greater than 2 MeV at geosynchronous orbit reached a

peak level of 11005 pfu.

IIB.  Geophysical Activity Forecast: The geomagnetic field is expected

to be at unsettled to minor storm levels on day one (17 May), quiet to

active levels on day two (18 May) and unsettled levels on day three (19

May).

III.  Event probabilities 17 May-19 May

Class M    15/15/05

Class X    05/05/01

Proton     05/05/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           16 May 131

Predicted   17 May-19 May 125/115/105

90 Day Mean        16 May 128

V.  Geomagnetic A Indices

Observed Afr/Ap 15 May  007/008

Estimated Afr/Ap 16 May  006/006

Predicted Afr/Ap 17 May-19 May  016/020-012/015-011/012

VI.  Geomagnetic Activity Probabilities 17 May-19 May

A.  Middle Latitudes

Active                30/30/25

Minor Storm           15/10/05

Major-severe storm    05/01/01

B.  High Latitudes

Active                10/15/15

Minor Storm           25/30/25

Major-severe storm    45/40/30