950
ACUS01 KWNS 302004
SWODY1
SPC AC 302002

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0302 PM CDT Mon Jun 30 2025

Valid 302000Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN PLAINS INTO THE MIDWEST AND MID ATLANTIC STATES...AND PARTS
OF THE DESERT SOUTHWEST AND WEST COAST...

...SUMMARY...
Isolated severe thunderstorms are possible across portions of the
southern Plains into the Midwest and the Mid-Atlantic, and in parts
of the Desert Southwest, and also in adjacent parts of southern
Oregon and northern California today.

...20Z Update...
Forecast scenario remains unchanged. See active Mesoscale
Discussions and the prior Outlook discussion below.

..Guyer.. 06/30/2025

.PREV DISCUSSION... /ISSUED 1128 AM CDT Mon Jun 30 2025/

...Southern OK/Northwest TX...
Morning visible satellite imagery confirms an outflow boundary
extending across central OK.  Strong heating to the south of the
boundary will lead to a very unstable air mass with dewpoints in the
mid 70s and MLCAPE values over 3000 J/kg.  Scattered thunderstorms
are expected to develop along the boundary by mid-afternoon,
propagating southward into north TX during the evening.  Winds aloft
are rather weak in this area, suggesting limited storm organization.
 However, the degree of instability and steep low-level lapse rates
will promote a risk of damaging wind in the stronger cells.  Hail
will also be possible in the strongest updrafts.

...PA/NY...
A warm and humid air mass is present once again across parts of
NY/PA, where daytime heating will lead to MLCAPE values of 1500-2000
J/kg.  Forecast soundings suggest ample mid-level moisture which
will be favorable for considerable coverage of storms, but may limit
the overall severe downdraft potential.  Nevertheless, a few strong
to severe cells capable of locally damaging wind gusts are possible.
 Refer to MCD #1522 for further details.

...NM/Southeast AZ...
Upper 40s and 50s dewpoints have become established across the
mountains of southern NM into southeast AZ.  Full heating will lead
to deep mixing and inverted-v profiles over the region.  Scattered
afternoon thunderstorms will likely result in gusty/damaging wind
gusts in some of this activity.

...Upper MI/WI...
A progressive shortwave trough over northern MN will track into the
Great Lakes region today, with cooling mid-level temperatures and
increasing large scale forcing.  This will lead to scattered
late-afternoon thunderstorms over parts of WI and the Upper MI.
Locally gusty winds and hail are possible in these storms.

...Northern CA/Southern OR...
Ahead of the weak upper trough immediately west of the CA coast,
southerly flow will aid in increasing mid-level moisture across
parts of northern CA and southern OR.  Ample heating coupled with
weak large-scale and orographic ascent will aid in isolated to
scattered high-based thunderstorm development.  Very steep lapse
rates will pose a risk of gusty/damaging winds.

$$