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000
FXXX12 KWNP 221230
DAYDIS

:Product: Forecast Discussion
:Issued: 2013 May 22 1230 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
#
#             Forecast Discussion
#
Solar Activity

.24 hr Summary...
Solar activity was low. The largest flare for the period was C2/1F flare
observed at 21/2237 UTC from Region 1756 (S21E47, Dai/beta).  Minor
magnetic complexity was noted in Regions 1753 (N04E41, Cro/beta), 1755
(N10E60, Dsi/beta), and 1756. Region 1748 showed gradual decay in its
intermediate spots. The delta configuration in its leader spots
gradually dissipated during the period as well. The remaining regions
showed little or no change. There were no Earth-directed coronal mass
ejections during the period.

.Forecast...
Solar activity is expected to be low during the period (22 - 24 May)
with a chance for an M-class flare and a slight chance for an X-class
flare.

Energetic Particle

.24 hr Summary...
The greater than 2 MeV electron flux at geosynchronous orbit was at
normal levels. The greater than 10 MeV proton flux at geosynchronous
orbit remained slightly enhanced (peak 1 pfu) and gradually decreased to
background levels.

.Forecast...
The greater than 2 MeV electron flux at geosynchronous orbit is expected
to be at normal levels on 22 May, increasing to normal to moderate
levels during 23 - 24 May in response to a recurrent coronal hole
high-speed stream (CH HSS). The greater than 10 MeV proton flux at
geosynchronous orbit is expected to remain at background levels for the
balance of the period.

Solar Wind

.24 hr Summary...
ACE data indicated minor changes in the solar wind flow. Speed ranged
from 380 to 499 km/s. IMF total field intensity (Bt) ranged from 1 to 6
nT. IMF Bz was variable in the 4/-5 nT range. Phi data indicated an away
(+) solar sector orientation during most of the period until
approximately 22/0200 UTC when it changed to a toward (-) orientation.

.Forecast...
Solar wind speed is expected to gradually increase during 22 - 23 May a
a recurrent CH HSS becomes geoeffective. WSA-Enlil model runs predict
peak speeds around 500 km/s with this CH HSS. Wind speed is expected to
remain enhanced on 24 May.

Geospace

.24 hr Summary...
The geomagnetic field was mostly at quiet levels with an isolated active
period from 22/0000 - 22/0300 UTC.

.Forecast...
Geomagnetic field activity is expected to increase to quiet to unsettled
levels on 22 May as a recurrent CH HSS becomes geoeffective. A further
increase to unsettled to active levels is expected on 23 May as the CH
HSS intensifies. Activity is expected to decrease to quiet to unsettled
levels on 24 May as CH HSS effects subside.