Day 2

Categorical Day 1 Outlook

Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.

Probability of one inch diameter hail or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of two inch diameter hail or larger within 25 miles of a point.

Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% or greater probability of wind gusts 65 knots or greater within 25 miles of a point.

000
ACUS01 KWNS 041246
SWODY1
SPC AC 041244

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0744 AM CDT Sat Apr 04 2020

Valid 041300Z - 051200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A SMALL
PART OF DEEP SOUTH TEXAS FOR ANOTHER 1-2 HOURS...

...SUMMARY...
A marginal hail threat may linger another hour or so over a small
part of deep south Texas.  Non-severe thunderstorms will be possible
today across parts of the southern Plains, lower Mississippi Valley
and West Coast.

...Synopsis/Discussion...
In mid/upper levels, a blocky pattern will persist over much of
Canada, related to a strong anticyclone over the Arctic Islands. 
Large-scale but low-amplitude ridging will prevail over the central
CONUS, as a persistent cyclone offshore from New England moves
farther out to sea.  A Pacific cyclone -- now evident in moisture-
channel imagery west of southern OR and northern CA near 128W -- is
forecast to move inland shortly after 18Z as an open-wave trough,
then weaken.  Associated large-scale ascent and low/middle-level
moisture will support general thunder potential over parts of
northern CA and southern OR to its east today.  This will occur as
an upstream perturbation  -- initially located west of Vancouver
Island near 134W -- digs south-southeastward and intensifies.  By
12Z tomorrow, the related closed cyclone should be located very near
the current position of its predecessor off northern CA, but
substantially stronger.

At the surface, 11Z analysis showed a cold front north-south over
lower MI, then arching across southern IN, western TN, northern LA,
the middle/upper TX coast, and deep south TX.  As this boundary
proceeds through the remainder of deep south TX, a frontal-wave low 
should form over the Gulf east of Padre Island and move east along
the boundary, over open water.

...Deep South TX...
See SPC mesoscale discussion 287 regarding a short-fused hail threat
over parts of deep south TX, along and south of the front, well-
sampled since by the 12Z BRO proximity sounding.  A small area of
hail probabilities has been added for this regime for another
(roughly) hour, with convection expected to weaken or move offshore.

Otherwise, isolated to scattered thunderstorms will move generally
eastward across the general thunder-outlook area through today, in a
regime of low-level warm advection and lift to LFC atop the elevated
frontal surface.  Severe potential will concentrate offshore, over
the northwestern Gulf, where a surface-based, supercell-favorable
parameter space will develop today and shift east-southeastward
south and east of the frontal-wave low.

..Edwards/Gleason.. 04/04/2020

$$
        

Day 3

Day 4