583
ACUS01 KWNS 072000
SWODY1
SPC AC 071958

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 PM CDT Sun Jul 07 2024

Valid 072000Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
MIDDLE/UPPER TEXAS COAST/FAR SOUTHWEST LOUISIANA...SOUTHERN
PLAINS...AND EASTERN COLORADO/FAR NORTHEAST NEW MEXICO...

...SUMMARY...
A few tornadoes will be possible along the middle to upper Texas
Coast into southwest Louisiana as Tropical Cyclone Beryl approaches
the coast and makes landfall later tonight. Scattered severe
thunderstorms are also expected across eastern Colorado, northeast
New Mexico, and parts of the southern Plains.

...20Z Update...
The Marginal and Slight Risks have been expanded southwestward
across western portions of the TX South Plains, where cumulus is
increasing this afternoon, and somewhat favorable instability and
deep-layer shear are already in place. Uncertainty remains rather
high regarding the potential for redevelopment across parts of
Oklahoma later this afternoon into the evening, in the wake of
substantial antecedent convection and outflow. However, relatively
strong heating is underway across parts of southwest/south-central
OK, and a few strong to severe storms remain possible by early
evening. No changes have been made to the Oklahoma portion of the
Slight Risk.

No changes have been made to the other Slight Risks. Scattered
strong to severe storms are still expected from the CO Front Range
into eastern CO/northeast NM. Also, for parts of the middle/upper TX
Coast into far southwest LA, the tornado threat is expected to
increase late tonight into early Monday morning, as Tropical Cyclone
Beryl approaches the coast. See the previous discussion below for
more details regarding these areas.

..Dean.. 07/07/2024

.PREV DISCUSSION... /ISSUED 1155 AM CDT Sun Jul 07 2024/

...Middle to Upper Texas Coast...
Tropical Cyclone Beryl and its outer envelope of strong low-level
flow, will continue to approach the Texas coast through much of the
period before making landfall tonight. Reference NHC for the latest
forecast details. Coincident with the expected strengthening of
lower tropospheric flow, low-level shear (i.e., enlarging
hodographs) will increase across the middle to upper Texas Coast
into southwest Louisiana through tonight, with embedded supercells
within the convective bands and transient rotating updrafts
potentially posing an isolated risk for tornadoes, especially into
tonight.

...Eastern Colorado/Front Range and far northeast New Mexico...
Low stratus persists at midday across east-central/southeast
Colorado toward the Raton Mesa vicinity, but more aggressive
clearing is occurring across northern Colorado. A belt of cyclonic
flow aloft will continue to overspread the region with some cooling
aloft, while low-level moisture and upslope flow both increase
through late today. Storms should develop near the foothills/I-25
later this afternoon and evening, likely with a bit
later-than-typical time frame for strong/severe thunderstorm
development. Moderate instability and strong shear will support
supercells capable of large hail, with some stronger wind gusts also
a possibility. Potentially severe storms may continue especially
across southeast Colorado/northeast New Mexico much of the night.

...Southern Plains including Oklahoma and North Texas/Panhandle...
A semi-organized cluster of storms has evolved across
east-central/south-central Oklahoma and may persist eastward early
this afternoon with a localized severe risk. Trailing outflow and a
residual surface cold pool are considerable factors in its wake,
although modification is likely into the afternoon. Storms may
redevelop as this occurs, potentially including parts of the Texas
Panhandle/Texas south Plains into western/southern Oklahoma and the
Red River vicinity, with isolated severe storms possible later this
afternoon through early evening.

...Iowa/northern Missouri/western Illinois to northern Wisconsin...
Surface pattern will remain relatively weak and ill-defined, but at
least widely scattered thunderstorms are expected particularly
across northern Missouri into Iowa and western Wisconsin near a weak
surface wave/boundary. Even with some cirrus and some residual early
day showers, moderate destabilization should occur across the
region, with development and intensification of storm clusters this
afternoon in the presence of 20-30 kt effective shear. Isolated
instances of wind damage is the most probable hazard, but some hail
could also occur. Some strong storms could occur as far north as
Wisconsin and perhaps the western Upper Peninsula of Michigan, but
the overall potential for organized severe storms should remain
limited.

...Southern Appalachians...
Short-term guidance substantiates the likelihood of scattered
thunderstorm development this afternoon, with some potential for
storms to cluster by late afternoon across upstate parts of the
Carolinas and far northeast Georgia. Mid-level lapse rates will be
weak with relatively tall/skinny CAPE, but some localized damaging
downbursts may occur.

$$