SPC AC 050600
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Mon Jun 05 2023
Valid 061200Z - 071200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SIERRAS/GREAT BASIN...SOUTHERN HIGH PLAINS...AND NORTHEASTERN
GEORGIA/SOUTH CAROLINA...
...SUMMARY...
Isolated strong to severe thunderstorms may occur Tuesday across
parts of the Sierras/Great Basin, southern High Plains, and
northeastern Georgia into South Carolina.
...Synopsis...
A stagnant upper-air pattern will persist over the CONUS on Tuesday,
with an upper ridge centered over the northern Plains and central
Canada. A closed upper low will remain over CA, with a separate
upper trough/low across the eastern CONUS and Canadian Maritime
provinces.
...Sierras/Great Basin...
High-based thunderstorms should develop by early Tuesday afternoon
across parts of the northern Sierras into the Great Basin as modest
large-scale ascent attendant to a upper low over CA overspreads this
area. Low-level moisture will remain quite limited, but diurnal
mixing of the boundary layer and corresponding steepening of
low-level lapse rates should encourage efficient convective
downdraft momentum transfer to the surface. 25-35 kt of deep-layer
shear should act to organize thunderstorms. Isolated severe wind
gusts may occur with the more robust cores as they spread generally
west-northwestward through the early evening. Occasional hail may
also occur with the initially more discrete thunderstorms before
clustering occurs.
...Southern High Plains...
Limited low-level moisture will remain over the southern High Plains
on Tuesday. Even with this region beneath mid-level ridging, most
guidance still suggests that at least isolated convection will
develop Tuesday afternoon along the higher terrain of
central/eastern NM and west TX. Around 20-30 kt of effective bulk
shear is forecast, mainly owing to modestly strengthening flow at
mid/upper levels. While this shear appears marginal for organized
convection, occasional instances of hail may occur with initial
robust cores, as steep mid-level lapse rates should be present. Some
upscale growth into loosely organized clusters will be possible by
early evening. With steepened low-level lapse rates from daytime
heating, isolated strong to severe wind gusts may occur before
thunderstorms eventually weaken with eastward extent.
...South Carolina/Georgia...
Thunderstorms may form by Tuesday afternoon along or just ahead of a
weak surface trough/front from northern GA into SC. This region will
be on the southwestern fringe of stronger flow aloft associated with
an upper low over the Northeast. Moderate instability is forecast to
develop through the day along/south of the trough/front, but
deep-layer shear should remain generally modest. Even so, any
convection that can develop may be capable of producing isolated
hail and damaging winds as it spreads east-southeastward to the
Atlantic Coast through Tuesday evening. Poor low-level convergence
and weak ascent aloft cast some uncertainty regarding overall
thunderstorm coverage.
...Northeast...
Weak instability may develop Tuesday in close proximity to the upper
low over portions of the Northeast. Thunderstorms that form across
parts of New England and move quickly east-southeastward could
produce occasional strong/gusty winds. However, confidence in
severe-caliber gusts remains too low to include any wind
probabilities at this time.
...South Florida...
Modestly enhanced mid-level west-southwesterly flow should be
present over south FL on Tuesday in association with a sub-tropical
jet. Even though large-scale ascent will remain nebulous, most
guidance indicates that isolated to scattered thunderstorms should
develop along various sea breezes Tuesday afternoon. Gusty winds and
small hail may occur with the strongest updrafts.
..Gleason.. 06/05/2023
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z