Subj : DAY2SVR: Marginal Risk
To   : All
From : Mike Powell
Date : Thu Aug 17 2023 07:40:00

ACUS02 KWNS 170602
SWODY2
SPC AC 170600

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Thu Aug 17 2023

Valid 181200Z - 191200Z

....THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
NEW ENGLAND...

....SUMMARY...
Isolated severe thunderstorms with a risk for mainly damaging gusts
will be possible across portions of New England on Friday.

....Northeast U.S...
An upper-level trough will close off into an upper low over the
northeast U.S./Ontario Province on Friday as a surface cold front
moves east in tandem with the upper trough. A seasonably warm/moist
air mass will exist in advance of the cold front with surface dew
points generally in the low/mid 60s. Mid-level southerly flow of
50-60 kts combined with low-level southerlies will result in
effective shear of 45-55 kts during the afternoon.

Showers/thunderstorms are expected to develop, or diurnally increase
in intensity, while moving northeast during the day as large-scale
ascent develops over the region. MLCAPE, modulated somewhat by cloud
cover, will generally range between 1000 and 1500 J/kg. This should
prove sufficient for isolated stronger storms, including supercell
structures and line segments, capable primarily of locally damaging
gusts and perhaps hail.

....Central/northern Plains...
North of a strengthening upper-level anticyclone over the southern
Plains, a pronounced shortwave trough will be located over the
southwestern portions of Canada.  In response, surface low pressure
should develop over SD in the vicinity of a surface trough, with
strong instability expected to develop by afternoon east of the
trough. Very warm mid-level temperatures associated with a
pronounced EML are expected to effectively suppress surface-based
thunderstorm development in this area.

....Southern Arizona...
An embedded disturbance within southeasterly mid-level flow on the
periphery of the expanding upper-level high may contribute to
locally greater thunderstorm coverage Friday, along with some risk
of strong gusts. Have opted not to introduce severe probabilities
with this outlook given low confidence on spatial coverage, but this
may be necessary with future outlooks.

...Bunting.. 08/17/2023

$$
--- SBBSecho 3.14-Linux
 * Origin: Ilink: CCO - capitolcityonline.net (454:1/105)

.