Severe WX Severe Weather Threat - June 23rd-27th, 2023

[atrainguy]

Still PDS warned.

 

[Taylor Campbell]

Appears to have lifted now.

 

[atrainguy]

 

[atrainguy]

Not sure if this is actually the tornado, but intense video nonetheless.

 

[atrainguy]

Pretty storm.

 

[atrainguy]

 

[andyhb]

This doesn’t seem good in Highlands Ranch.

 

[CheeselandSkies]

This doesn’t seem good in Highlands Ranch.

Yeesh. Jason Persoff is one of the old school chasers, used to see him in the TV documentaries from the '90s/early 2000s. Seems like the sort of fellow unlikely to be prone to hyperbole.

 

[buckeye05]

Some friends of mine who live in the Denver area are telling me it’s mostly just roof and tree damage, and pics seem to support that. Hoping the mass casualty report is hyperbole. Also I’m trying to remember the last time there was a tornado in the SW Denver suburbs? Can’t think of any off the top of my head.

 

[Taylor Campbell]

Check out these beans!

 

[CheeselandSkies]

Some interesting wording from NWS Omaha (bolded mine) regarding Saturday's potential in their CWA.

Saturday could spell trouble if that MCS doesn`t develop, turns
further south (leaving our air mostly undisturbed), or fizzles
earlier (leaving a boundary and mostly clear skies in the area).
All modes of severe weather would be possible in this secondary
solution. The RAP falls into this camp and would produce sfc CAPE
of 3000 J/kg, deep shear of 30-50 knots, quick lapse rates, and
hodographs resembling croquet hoops. Supercells could grow
powerful quickly. The SPC rightly has an area of "hatched" hail
along and east of the Missouri River suggesting the threat of hail
over 2" (Day 3). If this solution were to verify, convective
initiation may begin quickly near Omaha and/or the Missouri River
after lunch on Saturday.

Confidence in the ultimate outcome may not be particularly high
until seeing Friday night`s radar returns. All solutions carry a
threat of isolated flooding with marginal excessive rainfall
outlooks painted across the area.

 

[JBishopwx]

Today:

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR
SOUTHEASTERN MONTANA AND EASTERN WYOMING SOUTHEASTWARD TO
SOUTHWESTERN SOUTH DAKOTA AND CENTRAL NEBRASKA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS AN AREA
CENTERED OVER THE TEXAS PANHANDLE...

...SUMMARY...
Scattered severe thunderstorms -- capable of producing very large
hail and strong/damaging wind gusts and a tornado or two -- are
forecast from southeastern Montana and eastern Wyoming into
southwestern South Dakota and central Nebraska this afternoon and
tonight.

...Northern High Plains into Nebraska...
As convection currently ongoing across the northern High Plains
shifts northeastward across the Dakotas and Nebraska early in the
period, daytime heating is expected to commence across the northern
High Plains region, resulting in moderate destabilization. As a
short-wave trough shifts across the Intermountain West toward the
northern High Plains, afternoon/early evening storm development is
forecast. With increasing mid-level southwesterlies spreading atop
low-level easterly/southeasterly flow, initial storms will likely
become supercells, accompanied by large hail, as well as potential
for strong wind gusts and possibly a tornado or two.

Multiple clusters of storms should evolve with time, possibly
merging into one or more larger MCSs as a 45 kt southerly low-level
jet evolves across the central Plains. As the convection shifts
eastward across southern South Dakota and Nebraska, damaging wind
gusts would likely become more widespread, along with continued hail
potential. At least MRGL risk may persist well into the overnight
hours, possibly affecting the Mid Missouri Valley late in the
period.

...Southern High Plains...
Afternoon heating across the southern High Plains will contribute to
moderate destabilization, though the boundary layer will likely
remain capped for the most part. By late in the day, isolated
storms may develop from northeastern New Mexico into the Texas
Panhandle. Any storm which can develop would likely become
supercellular, given 30 to 40 kt mid-level westerlies atop southerly
flow prevailing over this region. Given the fairly deep mixed
layer, a couple of damaging wind gusts will be possible, along with
potential for large hail.

Some CAM guidance hints at upscale growth into an MCS, spreading
eastward either side of the Red River Valley. As such, an eastward
expansion of wind probabilities is being included at this time.

..Goss/Lyons.. 06/23/2023

 

[JBishopwx]

Saturday:

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE LOWER TO MID MISSOURI VALLEY AND MID TO UPPER MISSISSIPPI
VALLEY...

...SUMMARY...
Severe thunderstorms, associated with wind damage, isolated large
hail and perhaps a tornado or two, will be possible from parts of
the lower to mid Missouri Valley eastward into the mid to upper
Mississippi Valley Saturday afternoon and evening.

...Lower to Mid Missouri Valley/Mid to Upper Mississippi Valley...
An upper-level trough will move eastward across the north-central
U.S. on Saturday, as a 50 to 60 knot mid-level jet translates
eastward through the central Plains and mid Missouri Valley. At the
surface, a front will move eastward into the mid Missouri Valley.
Ahead of the front, surface dewpoints will be in the upper 60s and
lower 70s F. The moist airmass ahead of the front will gradually
heat up during the day, resulting in a corridor of moderate
instability by afternoon from northeast Kansas into northwestern
Missouri and Iowa. Convective initiation appears likely to occur on
the northern edge of the stronger instability from southeastern
Nebraska into western Iowa during the late morning and early
afternoon. The storms are forecast to move eastward across Iowa
during the afternoon and should develop southward into northern and
central Missouri during the late afternoon and early evening.

NAM forecast soundings by late Saturday afternoon, in south-central
Iowa along the instability axis, have MLCAPE in the 1500 to 2500
J/kg range and 700-500 mb lapse rates near 7.0 C/km. This, combined
with 0-6 km shear of 50 to 60 knots, should be favorable for
supercells with large hail. Hailstones of greater than 2 inches in
diameter will be possible with the more dominant supercells.
Low-level flow is forecast to gradually increase during the late
afternoon and early evening, with 0-3 km storm-relative helicity
reaching 250 m2/s2 in parts of southern and central Iowa. This is
expected to support a tornado threat with the stronger rotating
storms. In addition, a wind-damage threat will likely occur with
supercells and/or short bowing line segments.

Further south into northern and central Missouri, low to mid-level
temperatures are forecast to be considerably warmer, with 700 mb
temperatures from +11 to +13 C. This, combined with a lack of
large-scale ascent, should keep convective coverage isolated during
the late afternoon and early evening. However, any supercell that
can develop within this moist and unstable airmass should be
associated with a severe threat. Large hail and wind damage will be
the primary threats in most areas across Missouri.

 

[JBishopwx]

 

[atrainguy]

Looks like Saturdays 5% tornado risk extended east a smidge, touching the Illinois border.

Storm Prediction Center Apr 16, 2024 0600 UTC Day 2 Convective Outlook

Severe weather, tornado, thunderstorm, fire weather, storm report, tornado watch, severe thunderstorm watch, mesoscale discussion, convective outlook products from the Storm Prediction Center.

www.spc.noaa.gov

 

[Taylor Campbell]

The tornado risk today has been going up.

 

[atrainguy]

 

[atrainguy]

Still a radar indicated Tornado Warning in Wyoming. Meanwhile the Southern Plains have severe thunderstorm watch, with tornadoes a possibility.

 

[atrainguy]

Got an "observed" warning in Wyoming.





Don't know if this is the same tornado, but this pic was posted almost 15 minutes ago.

 

[andyhb]

That’s the same tornado yes, likely significant.