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FXXX02 KWNP 180425

:Product: 27-day Space Weather Forecast
:Issued: 2015 May 18 0402 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
#               27-day Space Weather Forecast
Forecast of Solar and Geomagnetic Activity
18 May - 13 June 2015

Solar activity is expected to be at very low levels with a chance
for C-class flares and a slight chance of M-class flares on 18 May
before decreasing further to only a chance for C-class flares once
Region 2339 rotates fully around the west limb on 19 May. The chance
for M-class activity increases on 25 May with the return of old
Region 2335 (S15, L=192) and remain elevated through the remainder
of 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 moderate to high levels from 18-28 May due to
residual effects from last weeks negative polarity CH HSS followed
by effects from an anticipated positive polarity HSS due to become
geoeffective on 18 May. Normal to moderate levels are expected to
prevail with the exception of 31 May-01 Jun, 04-06 Jun, and 10-12
Jun following various recurrent CH high speed streams.

Geomagnetic field activity is expected to be quiet to active on
18-19 May due to effects from a positive polarity CH HSS. Mostly
quiet conditions are expected from 20 May to 01 Jun. Quiet to
unsettled conditions with a chance for active periods are expected
on 02-03 Jun due to effects from a negative polarity HSS followed by
quiet conditions through 06 Jun. Unsettled conditions are expected
on 07 and 10 Jun as well as active to minor storm conditions on
08-09 Jun due to the anticipated return of the recurrent negative
polarity CH HSS that yielded major storm conditions this week.
Mostly quiet conditions are expected for the remainder of the
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