869
ACUS02 KWNS 140537
SWODY2
SPC AC 140535

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1235 AM CDT Mon Jul 14 2025

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
NEBRASKA AND SOUTH DAKOTA...

...SUMMARY...
Strong to severe thunderstorms are possible Tuesday afternoon and
evening across portions of the central Plains to Upper Midwest. A
greater concentration of severe wind gusts and hail will be focused
mainly across parts of Nebraska and South Dakota.

...Northern/Central Plains to Upper Midwest...

A positive-tilt upper shortwave trough is forecast to eject eastward
across the northern Rockies on Tuesday. Another shortwave impulse
ahead of this main system will move across SD/NE and into the Upper
Midwest. Both of these features will result in increasing mid/upper
westerly flow. In response to increasing flow and height falls, a
surface low will develop over western SD and move into southern MN
by Wednesday morning. Meanwhile, a cold front will sag southward
across MT, the Dakotas and northern MN, while a surface trough
extends southward into the central High Plains.

Ahead of the triple point within the warm sector south of the cold
front, mid/upper 60s F dewpoints will be in place beneath steep
midlevel lapse rates. This will foster 2000-3000 J/kg MLCAPE.
Vertical shear around 25-35 kt will support a mix of cells and
clusters capable of producing damaging gusts and hail. Most guidance
suggest some upscale growth will occur via clustering/consolidating
outflows by late afternoon across parts of SD/NE. A 30-40 kt
southwesterly low-level jet developing by early evening could aid in
maintaining a bowing MCS with eastward extent toward the MO River.
If this occurs, an increasing risk for severe wind gusts will be
possible. Given a consistent signal across forecast guidance and a
favorable forecast environment, a Slight risk (level 2 of 5) has
been included, mainly for parts of NE/SD.

Additional strong to isolated severe storms will be possible along
the sagging cold front into northern MN, as well as across eastern
WY and western SD/NE in the post-frontal upslope flow regime.
Isolated hail and strong gusts will be possible with these storms.

...Mid-MS Valley...

Forecast guidance has trended weaker with a prior depiction of a
weak low/MCV across the Ozarks/Mid-MS Valley vicinity. A very moist
airmass (70s F dewpoints) will be in place, supporting modest
instability (1000-1500 J/kg MLCAPE). However, vertical shear is
forecast to be very weak (around 15 kt), limiting potential for
organized/longer-lived updrafts. Where stronger heating occurs,
steepened low-level lapse rates could support sporadic strong
downburst winds. Overall severe potential appear limited and the
Marginal risk (level 1 of 5) has been removed with this update.

..Leitman.. 07/14/2025

$$