lunedì 31 agosto 2015

Propagation outlook from Boulder

:Product: Weekly Highlights and Forecasts
:Issued: 2015 Aug 31 0458 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
#
#                Weekly Highlights and Forecasts
#
Highlights of Solar and Geomagnetic Activity 24 - 30 August 2015

Solar activity ranged from low to high levels. Low levels were
observed on 25-26 and 29 Aug, moderate (R1-minor) levels on 27-28
and 30 Aug while high (R2-moderate) levels occurred on 24 Aug. The
vast majority of activity was observed from Region 2403 (S15, L=193,
class/area Fkc/1190 on 25 Aug). In total, this region produced a
total of 58 C-class and six M-class flares. Region 2405 (S19, L=089,
class/area Cro/020 on 29 Aug) produced a total of four weak C-class
flares.

The period began at high levels as Region 2403 produced an impulsive
M5/1b flare at 24/0733 UTC. Later on the 24th, the region produced
an M1 flare at 24/1746 UTC. On 27-28 Aug, Region 2403 produced a
total of three M-class flares; an M2/1n at 27/0544 UTC, an M2/1f at
28/1316 UTC and an M2/1n at 28/1903 UTC. The period ended when
Region 2403 produced a long duration M1 flare at 30/0330 UTC. During
the period, no Earth-directed coronal mass ejections (CMEs) were
detected.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at
high levels on 24-25 and 29 Aug and moderate levels on 26-28 and 30
Aug. The peak flux observed during the summary period was 1,840 pfu
at 25/1700 UTC.

Geomagnetic field activity ranged from quiet to major storm levels.
Quiet to unsettled levels were observed on 24-25 Aug due to waning
effects from a positive polarity coronal hole high speed stream (CH
HSS). Solar wind parameters reflected a nominal wind environment
with speeds decreasing from about 500 km/s to near 350 km/s by late
on 25 Aug. Early on 26 Aug, geomagnetic field conditions increased
to unsettled to minor storm (G1-minor) levels due to transient
effects from the 22 Aug CME. Geomagnetic activity further increased
on 27 Aug to active to major storm (G2-moderate) levels and
persisted at these levels through 28 Aug. During this time frame,
wind speeds were unimpressive averaging about 350 km/s but the total
interplanetary magnetic field (Bt) peaked at 14 nT coupled with
steady southward Bz to -12 nT.

Activity levels remained elevated on 29 Aug at quiet to minor storm
levels due to effects from a co-rotating interaction region in
advance of an equatorial, negative polarity CH HSS. Wind speeds
approached 510 km/s with peak Bt values of 17 nT and peak southward
Bz briefly reached -15 nT. 30 Aug saw quiet geomagnetic field
conditions with solar wind parameters indicating a return to more
nominal levels.

FORECAST OF SOLAR AND GEOMAGNETIC ACTIVITY 31 AUGUST-26 SEPTEMBER 2015

Solar activity is expected to be at very low to low levels from 31
Aug - 10 Sep and again from 25-26 Sep. From 11-24 Sep, activity
levels are expected to increase to low to moderate (R1-minor) due to
the return of old Region 2403 (S15, L=193).

No proton events are expected at geosynchronous orbit barring any
significant flare activity from returning region 2403 during 11-24
Sep.

The greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at normal to moderate levels on 31 Aug - 02 Sep,
07-12 Sep, 19 Sep and 22-25 Sep. High flux levels are expected on
03-06 Sep, 13-18 Sep, 20-21 Sep and 26 Sep.

Geomagnetic field activity is expected to be at minor storm
(G1-minor) levels on 01-02 Sep and 19 Sep due to positive polarity
CH HSS effects. Unsettled to active levels are expected on 03-04
Sep, 12-16 Sep, 18 Sep, 20 Sep and 24-25 Sep due to positive
polarity CH HSS effects. Mostly quiet levels are expected for the
remainder of the outlook period.

:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2015 Aug 31 0459 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/wwire.html
#
#      27-day Space Weather Outlook Table
#                Issued 2015-08-31
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2015 Aug 31      90           8          3
2015 Sep 01      90          20          5
2015 Sep 02      85          22          5
2015 Sep 03      85          15          4
2015 Sep 04      85          10          3
2015 Sep 05      85           8          3
2015 Sep 06      85           8          3
2015 Sep 07      85           5          2
2015 Sep 08      85           5          2
2015 Sep 09      85           5          2
2015 Sep 10      85           5          2
2015 Sep 11      95           5          2
2015 Sep 12     105          12          3
2015 Sep 13     115          15          4
2015 Sep 14     115          10          3
2015 Sep 15     115           8          3
2015 Sep 16     115          10          3
2015 Sep 17     115           5          2
2015 Sep 18     115           8          3
2015 Sep 19     115          20          5
2015 Sep 20     115          10          3
2015 Sep 21     115           5          2
2015 Sep 22     115           5          2
2015 Sep 23     110           5          2
2015 Sep 24     105          15          4
2015 Sep 25     100          10          3
2015 Sep 26      90           5          2
(SWPC via DXLD)