Weekly Highlights of Solar and Geomagnetic Activity, 13 - 19 March 2017
 

:Product: Weekly Highlights and Forecasts
:Issued: 2017 Mar 20 0323 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/weekly.html
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# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity
13 - 19 March 2017

Solar activity was at very low levels with no observable spots on
the solar disk. No Earth-directed CMEs were observed during the
period.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
normal to moderate levels with high levels observed on 13-15 March.
The largest flux value of the period was 8,800 pfu observed at
14/1655 UTC.

Geomagnetic field activity ranged from quiet to unsettled levels.
Solar wind speed was at nominal levels between 300 km/s and 400 km/s
through most of the period with total field near 5 nT. On 15-16
March, a slight increase in solar wind speed and total field was
observed just after a solar sector boundary crossing at 15/0008 UTC.
This was likely due to a weak connection to a positive polarity
coronal hole high speed stream (CH HSS). Total field increased to 9
nT while solar wind speed increased to near 433 km/s. The
geomagnetic field responded with isolated unsettled periods on 15
and 16 March.

Forecast of Solar and Geomagnetic Activity
20 March - 15 April 2017

Solar activity is expected to be at very low levels for the forecast
period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal to moderate levels with high levels likely
on 24 March and again from 29 March - 11 April due to recurrent CH
HSS activity.

Geomagnetic field activity is expected to be at unsettled to active
levels on 21-24 March and again from 28 March - 06 April. G1 (Minor)
geomagnetic storm levels are likely on 23, 28-31 March and 02 April
while G2 (Moderate) geomagnetic storm levels are likely on 28-29
March due to recurrent CH HSS effects.