122
ACUS01 KWNS 050545
SWODY1
SPC AC 050544

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1244 AM CDT Wed Jun 05 2024

Valid 051200Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE UPPER
MIDWEST...EASTERN GREAT LAKES...NORTHEAST...MID-ATLANTIC...AND THE
TEXAS COASTAL PLAIN TO THE ARKLAMISS...

...SUMMARY...
Strong storms are possible across portions of the Upper Midwest,
Great Lakes, Northeast, Mid-Atlantic, and Texas Coastal Plain to the
ArkLaMiss.

...Synopsis...
A large mid-level ridge will build across the western CONUS today
with a downstream trough amplifying across the Upper Midwest. A cold
front will extend from a surface low in southern Manitoba across the
western Great Lakes and into the Mid-Mississippi Valley this morning
and move east across the Great Lakes/Ohio Valley through the day.

...Minnesota/Wisconsin...
Scattered thunderstorms are expected across the Upper Midwest as
strong height falls associated with the amplifying mid-level trough
overspread the region. Cooling temperatures aloft and at least some
low-level moisture recovery should sufficiently destabilize the
region for strong updrafts. Strong unidirectional westerly flow will
increase from 30 knots at 700mb to 60 knots at 500mb and nearly 100
knots at 300mb. This wind profile will support organized updrafts
with the potential for large hail and particularly wind, given the
steep low-level lapse rates and the strong unidirectional flow.

...East Texas to the ArkLaMiss...
The MCS currently near the Red River at 06Z is expected to continue
through the early morning hours and exist from east Texas to
northern Louisiana by 12Z. Some isolated severe wind gusts are
possible through the morning hours given the very moist airmass in
place and the well established cold pool associated with the MCS.
However, expect it to continue to weaken through the morning as it
moves toward increasingly warm 700mb temperatures and weakening
shear with the MCS eventually moving into the Gulf of Mexico near
mid-day. The severe threat may continue into the afternoon across
eastern Louisiana and southwest Mississippi where at least some
heating may result in destabilization. However, relatively weak
shear should limit a greater potential or the threat for more than
isolated damaging wind gusts.

...Southern Edwards Plateau into portions of Deep South Texas...
An outflow boundary from the overnight MCS across eastern Texas will
likely stall somewhere near central Texas in a region where a very
moist airmass and extreme instability will be present. Overall
height rises will not be favorable for thunderstorm development.
However, the extension of a mid-level (likely convectively modified)
shortwave trough is expected to move southeast across
central/eastern Texas during the afternoon. This trough may provide
enough support, when combined with low-level convergence along any
remnant outflow boundary, for isolated thunderstorm development this
afternoon/evening. Very weak flow (less than 20 knots) in the
vertical wind profile, should mitigate more than isolated damaging
wind/large hail threat with this activity.

...Ohio Valley/Eastern Great Lakes...
A very moist airmass across the lower-Ohio River valley will advect
north through the day today with upper 60s to low 70s dewpoints
expected ahead of the cold front from the Ohio River to eastern
Michigan by late morning. Only minimal heating will be required for
convective initiation today. This lack of an EML or greater capping
will limit the overall threat with scattered thunderstorm
development expected along and ahead of the cold front by midday.
Greater forcing along the cold front may be needed for stronger
storms capable of isolated large hail and damaging wind gusts.

...Mid-Atlantic...
Widespread cloud cover is expected across northern Virginia and the
DelMarVa as a moist airmass advects into the region. Any minimal
heating which occurs will be sufficient for scattered storm
development during the afternoon. Very weak lapse rates (<6 C/km)
should limit more robust updraft development. However, if any
stronger/ more sustained storms can develop, there will be some
threat for isolated damaging wind gusts or perhaps a tornado as a
small, but favorably curved, low-level hodograph will be present
across this region.

...Northeast...
Scattered thunderstorms are expected to develop amid weak height
falls and moderate instability across New Hampshire and
southern/central Maine this afternoon. Straight hodographs and
strengthening northwesterly flow above 500mb may be sufficient for
some storm organization including transient supercell structures
capable of large hail.

..Bentley/Lyons.. 06/05/2024

$$