Information from NOAA Storm Prediction Center at this website

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SPC Day 1 Outlook

Updates are issued at 0600 UTC, 1300 UTC, 1630 UTC, 2000 UTC, 0100 UTC - Current UTC time: May 27 2018 9:55 am

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Day 2

Categorical Day 1 Outlook

ACUS01 KWNS 270600
SPC AC 270559

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1259 AM CDT Sun May 27 2018

Valid 271200Z - 281200Z


Severe storms are possible later today into this evening primarily
from the northern through southern High Plains. A modest threat for
a few tornadoes will also exist across the Florida Peninsula.


Cutoff upper low circulation situated over the Great Basin will
advance very slowly east today with downstream ridge shifting east
through the Plains and MS Valley region. At the surface a
northern-stream low-amplitude shortwave trough moving through
southern Manitoba will provide the impetus for a cold front to
continue south into the northern Plains and upper MS Valley. Farther
south a dryline will become established over the central through
southern High Plains. Subtropical Storm Alberto is forecast by the
National Hurricane center to continue north through the eastern

...High Plains region and central Rockies...

Post-frontal upslope flow will persist across WY where some low
clouds may linger into early afternoon. Farther east into the High
Plains dewpoints generally in the 50s and steep lapse rates will
support moderate to strong instability as the boundary layer warms
during the afternoon with MLCAPE from 1500-2500 J/kg likely. Several
vorticity maxima moving through the upper low circulation will lift
north through the Rockies and into portions of the High Plains.
Multiple areas of thunderstorm initiation are likely, including
within upslope regime over the higher terrain of WY as well as
farther south along dryline across the central through southern High
Plains, where the best wind profiles for a few high based supercells
will exist. Otherwise, multicell storms will be the dominant mode.
Storms may remain more discrete with southward extent into the
plains before weakening during the evening, but some upscale growth
into lines/clusters may occur from WY into western NE and the
western Dakotas where storms may persist into the overnight. Large
hail and damaging wind are expected to be the main threats.  

...FL through southeast GA...

Subtropical storm Alberto is forecast by the NHC to advance north
and northwest through the eastern Gulf. Satellite imagery shows
middle to upper-level dry air entraining into the west and southern
portions of the storm, and this should increase the chance of
diabatic heating in between the outer convective bands today. A
broad low-level jet east of the center will augment 0-2 km
hodographs over the southern two thirds of the FL Peninsula during
peak heating, supporting a threat for mini supercells capable of a
few tornadoes later today. At least a marginal risk for a couple of
tornadoes will extend farther north into southeast GA by late
afternoon or evening.

..Dial/Marsh.. 05/27/2018


Day 3

Day 4

Largly based on original scripts from Ken True: and Rick Curly: