Product: Weekly Highlights and Forecasts
:Issued: 2017 Sep 04 0551 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact http://www.swpc.noaa.gov/wwire.html#
# Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 28 August - 03 September 2017
Solar activity ranged from very low to low levels. Very low levels were observed on 31 Aug while low levels dominated the period from 28-30 Aug and again from 01-03 Sep. The period began as Regions 2673 (S10, L=117, class/area Dsc/130 on 03 Sep) and 2674 (N14, L=103, class/area Fhc/930 on 03 Sep) were rotating onto the east limb as simple alpha and beta magnetic configurations on 28-29 Sep, respectively. Region 2672 (N08, L=227, class/area Dao/270 on 22 Aug) was in decay as it approached the west limb on 01 Sep. By midday on 01 Sep, Region 2674 began a growth phase which increased its overall area to approximately 930 millionths and produced 12 C-class flares that included a C5/Sf at 30/1845 UTC. Region 2673 began a slow growth phase on 02 Sep, however rapid spot development occurred on 03 Sep increasing its area to approximately 130 millionths with a Dsc/beta-gamma spot classification. The largest flare of the period was a C7 observed at 02/1541 UTC, with an associated Type II (976 m/s) radio burst and non-Earth directed coronal mass ejection(CME),from Region 2672.
An earlier CME was observed off the west limb on SOHO/LASCO C3 imagery at approximately 28/1930 UTC. This CME was analyzed and it was determined there was a possibility of a glancing blow on 01 Sep, however no definitive signs were observed in solar wind data. No proton events were observed at geosynchronous orbit.
The greater than 2 MeV electron flux at geosynchronous orbit was at normal levels on 30-31 Aug, moderate levels on 28 Aug, and at high levels on 29 Aug and 01-03 Sep. The largest flux of the period was 12,319 pfu observed at 03/1705 UTC.
Geomagnetic field activity ranged from quiet to G1 (Minor) storm levels during the period. Solar wind speed appeared to be in decline from approximately 500 km/s to around 350 km/s by 29 Aug with total field around 6-8 nT. Solar wind speed, temperature, and density was unreliable in DSCOVR solar wind data between 28/0600 UTC and 29/1655 UTC. A solar sector boundary crossing into a negative sector was observed at approximately 29/1925 UTC with a brief increase in total field to 13 nT. The Bz component deflected southward to -10 nT. The geomagnetic field responded with quiet levels on 28 and 30 Aug while quiet to active levels were observed on 29 Aug.
At approximately 31/0100 UTC total field began to increase, phi angle switched into a positive sector, and solar wind speed and temperature began to rise as a positive polarity coronal hole high speed stream (CH HSS) moved into a geoeffective position. Total field reached a maximum of 30 nT at 31/0615 UTC. Solar wind speed was mostly between 530 km/s to 680 km/s through 03 Sep and then began to decline to approximately 480 km/s by the end of the period.
The geomagnetic field responded with quiet to G1 (Minor) storm levels on 31 Aug and 02 Sep, quiet to active levels on 01 Sep, and quiet to unsettled levels on 03 Sep. Forecast of Solar and Geomagnetic Activity 04 September - 30 September 2017 Solar activity is expected to be at low levels with a chance for M-class (R1-R2, Minor-Moderate) flares from 04-11 Sep and again from 14-30 Sep due to potential significant flare activity from Region 2673, 2674, and the return of old Region 2672. Very low levels are expected from 12-13 Sep. 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 on 07, 13, 21-27 Sep. High levels are expected on 04-06, 08-12, 14-20, and 28-30 Sep due to CH HSS influence.
Geomagnetic field activity is expected to be at unsettled to active levels on 04, 07-09, 13-17, 27-30 Sep with G1 (Minor) geomagnetic storm levels likely on 13-16, 27-29 Sep and G2 (Moderate) storm levels likely on 14-15 Sep due to recurrent CH HSS activity.
Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2017 Sep 04 0551 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC web contact http://www.swpc.noaa.gov/wwire.html#
# 27-day Space Weather Outlook Table
# Issued 2017-09-04
#
# UTC Radio Flux Planetary Largest
# Date 10.7 cm A Index Kp Index
2017 Sep 04 120 10 4
2017 Sep 05 118 8 3
2017 Sep 06 116 5 2
2017 Sep 07 116 15 4
2017 Sep 08 116 15 4
2017 Sep 09 105 8 3
2017 Sep 10 90 5 2
2017 Sep 11 85 5 2
2017 Sep 12 80 5 2
2017 Sep 13 80 25 5
2017 Sep 14 85 30 6
2017 Sep 15 85 30 6
2017 Sep 16 85 25 5
2017 Sep 17 85 12 4
2017 Sep 18 88 5 2
2017 Sep 19 92 5 2
2017 Sep 20 92 8 3
2017 Sep 21 92 5 2
2017 Sep 22 95 5 2
2017 Sep 23 98 8 3
2017 Sep 24 100 5 2
2017 Sep 25 105 8 3
2017 Sep 26 110 5 2
2017 Sep 27 110 20 5
2017 Sep 28 110 20 5
2017 Sep 29 110 20 5
2017 Sep 30 110 12 4
(NOAA)