lunedì 10 aprile 2017

Propagation outlook from Boulder

:Product: Weekly Highlights and Forecasts
:Issued: 2017 Apr 10 0321 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
03 - 09 April 2017

Solar activity ranged from very low to high during the period due to
multiple M-class flares from Region 2644 (N13, L=57, class/area
Fkc/520 on 03 April). The first was an M1/Sf flare observed at
03/0105 UTC. The second M-flare was an M5/2n at 03/1429 UTC with an
associated Type II (estimated shock speed 746 km/s) and Type IV
radio sweeps. Coronal mass ejections (CMEs) were observed with both
flares, however, neither was deemed to be Earth-directed. 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 on 05-08 April, high levels on 04, 09
April, and very high levels on 03 April. The largest flux of the
period was 53,552 pfu at 03/1330 UTC.

Geomagnetic field activity ranged from quiet to G1 (Minor) storm
conditions. The period began under the influence of a southern
polar, negative polarity, coronal hole high-speed stream (CH HSS).
Total field ranged between 2 and 6 nT until approximately 04/0000
UTC when it began to increase to a period maximum of 16 nT at
04/1019 UTC. The Bz component reached a period minimum value of -13
nT at 04/0932 UTC. Total field values were at near nominal levels
between 05/2200 and 07/2000 when Bt ranged from 2 to 7 nT. An
additional enhancement in the interplanetary magnetic field occured
shortly after 07/2000 UTC when Bt increased to 10 nT in conjunction
with a solar sector boundary crossing (SSBC) from a negative to a
positve solar sector orientation. Solar wind speed began the period
near 445 km/s and peaked to a maximum speed of 680 km/s at 08/1544
UTC. The geomagnetic field responded with G1 (Minor) storm
conditions on 04, 09 April, and quiet to active levels on 03, 05-08
April.

Forecast of Solar and Geomagnetic Activity
10 April - 06 May 2017

Solar activity is expected to be very low with a slight chance for
C-class flare activity on 10-17 April and 05-06 May. Solar activity
is likely to be at moderate levels (R1-R2, Minor-Moderate) with a
slight chance for X-class flares (R3-Strong or greater) on 18-30
April and 01-04 May due to potential in Regions 2644 and 2645 (S10,
L=18, class/area Ekc/700 on 03 April).

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
from 10-12, 18-28 April and 01, 06 May with very high levels likely
on 29-30 April due to CH HSS influence.

Geomagnetic field activity is expected to be at unsettled to active
levels on 10-13, 17-19, 23-29 April, and 01-06 May with G1 (Minor)
storm levels likely on 17, 23-27 April and G2 (Moderate) storm
levels likely on 23 April due to recurrent CH HSS effects. Quiet
conditions are expected for the remainder of the period.

:Product: 27-day Space Weather Outlook Table 27DO.txt
:Issued: 2017 Apr 10 0321 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 2017-04-10
#
#   UTC      Radio Flux   Planetary   Largest
#  Date       10.7 cm      A Index    Kp Index
2017 Apr 10      72          12          4
2017 Apr 11      72           8          3
2017 Apr 12      72           8          3
2017 Apr 13      72           8          3
2017 Apr 14      72           5          2
2017 Apr 15      72           5          2
2017 Apr 16      75           5          2
2017 Apr 17      85          20          5
2017 Apr 18      88          18          4
2017 Apr 19      88          10          3
2017 Apr 20      95           5          2
2017 Apr 21      95           5          2
2017 Apr 22      92           5          2
2017 Apr 23      92          55          6
2017 Apr 24      90          28          5
2017 Apr 25      90          20          5
2017 Apr 26      90          22          5
2017 Apr 27      90          28          5
2017 Apr 28      90          15          4
2017 Apr 29      90           8          3
2017 Apr 30      80           5          2
2017 May 01      78          20          4
2017 May 02      78          10          3
2017 May 03      72           8          3
2017 May 04      72          10          3
2017 May 05      75          15          4
2017 May 06      75          15          4
(SWPC via DXLD)