Monday, August 20, 2018

Weekly Propagation Forecast Bulletins


Product: Weekly Highlights and Forecasts
:Issued: 2018 Aug 20 0445 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC link http://www.swpc.noaa.gov/weekly.html
#
#                Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 13 - 19 August 2018

Solar activity was very low. Two small regions developed on the visible disk this period. Region 2718 (S07, L=191, class/area Hrx/020 on 17 Aug) developed on 14 Aug and decayed to plage by 19 on Aug. Region 2719 (S06, L=133, class/area Bxo/010 on 19 Aug)  developed in the SE quadrant on the 19 August. No significant flare events occurred from either region. Other activity included a filament eruption centered near S11W04 observed lifting off the solar disk at approximately 19/0538 UTC. An associated coronal mass ejection was observed off the SW limb in SOHO/LASCO C2 imagery at 19/0812 UTC. WSA/Enlil modelling of the event suggested the ejecta was primarily directed to the westward of the Sun-Earth line and is not expected to cause any significant effects.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at normal levels on 13-15 Aug, moderate levels on 16-17 Aug, and at high levels on 18-19 Aug. The largest flux of the period was 18,287 pfu observed at 19/1800 UTC.

Geomagnetic field activity ranged from quiet to active levels over the period. Solar wind speed was at nominal levels at the beginning of the period with solar wind speed ranging from 310-430 km/s while the total field was between 1-4 nT. The geomagnetic field was quiet on 13-14 Aug. By 15 Aug, solar wind speed increased to approximately 450-500 km/s with total field increasing to a maximum of 14 nT by 16/1005 UTC as a positive polarity coronal hole high speed stream (CH HSS) moved into geo effective position. A further increase in solar wind speed to near 570 km/s was observed late on 17 Aug before slowly receding to nominal levels by midday on 19 Aug. The geomagnetic field that responded with quiet to active levels on 15-18 Aug. By late on 19 Aug, total field increase again to 12 nT along with an increase in solar wind to near 550 km/s as a negative polarity CH HSS was becoming geoeffective. However, only quiet levels were observed on 19 Aug.

Forecast of Solar and Geomagnetic Activity 20 August - 15 September 2018

Solar activity is expected to continue at very low levels.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to reach high levels on 22-27 Aug and again on 13-15 Sep due to CH HSS influence.

Geomagnetic field activity is expected to be unsettled to active levels on 20-25 Aug, 03-04 Sep, 07 Sep, and 11-15 Sep with a chance for G1 (Minor) geomagnetic storm levels on 20-21 Aug due to the recurrent of CH HSS activity.

Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2018 Aug 20 0445 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC link http://www.swpc.noaa.gov/wwire.html
#
#      27-day Space Weather Outlook Table
#                Issued 2018-08-20
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2018 Aug 20      67          20          4
2018 Aug 21      67          18          4
2018 Aug 22      67          12          4
2018 Aug 23      67          12          4
2018 Aug 24      66          10          3
2018 Aug 25      66           8          3
2018 Aug 26      66           5          2
2018 Aug 27      66           5          2
2018 Aug 28      66           5          2
2018 Aug 29      66           5          2
2018 Aug 30      66           5          2
2018 Aug 31      66           5          2
2018 Sep 01      66           5          2
2018 Sep 02      66           5          2
2018 Sep 03      66          12          4
2018 Sep 04      66           8          3
2018 Sep 05      66           5          2
2018 Sep 06      67           5          2
2018 Sep 07      67           8          3
2018 Sep 08      67           5          2
2018 Sep 09      67           5          2
2018 Sep 10      67           5          2
2018 Sep 11      68          15          4
2018 Sep 12      68          15          4
2018 Sep 13      68          12          4
2018 Sep 14      68          12          4
2018 Sep 15      68          10          3
(NOAA)