Mesoscale Discussion 1303

Issued

Jul 17, 2021, 7:27 AM CDT (12:27 UTC)

Expired

Jul 17, 2021, 9:30 AM CDT

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch unlikely

Chance of a watch

5%

The Wichita radar (KICT), 71 km from the middle of the area, began a volume at 12:30 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

236 
ACUS11 KWNS 171227
SWOMCD
SPC MCD 171227 
ARZ000-MOZ000-OKZ000-KSZ000-NEZ000-171430-

Mesoscale Discussion 1303
NWS Storm Prediction Center Norman OK
0727 AM CDT Sat Jul 17 2021

Areas affected...central Kansas into northwest Arkansas

Concerning...Severe potential...Watch unlikely 

Valid 171227Z - 171430Z

Probability of Watch Issuance...5 percent

SUMMARY...Occasional strong thunderstorm winds, briefly approaching
60 mph at times, may occur this morning with thunderstorms across
central Kansas into northeast Oklahoma. A watch should not be needed
this morning.

DISCUSSION...Showers and thunderstorms continue across central
Kansas into northwest Arkansas associated with persistent warm-air
advection in the 925-850 millibar layer. Tall, skinny CAPE profiles
yielding effective-layer CAPE around 1500 J/kg and precipitable
water values between 1.5 and 2.0 inches may support an occasional
water-loaded downdraft capable of producing thunderstorm winds
around 60 mph this morning. However, modest low-level and mid-level
lapse rates of 5.5-6.5 C/km and weak effective-layer shear
(generally less than 20 knots) should limit a more widespread severe
wind threat. 

Farther north, across north-central Kansas, thunderstorms have
recently intensified along the leading edge of a remnant MCV from
overnight convection.  Here, effective-layer shear is a little
better than farther south (generally around 25 knots). This may
support a slightly more organized wind threat than farther south,
but similar low-level and mid-level lapse rates as farther south and
weaker instability should limit the overall severe potential.

In both scenarios, a watch is not currently expected.

..Marsh/Thompson.. 07/17/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...LZK...SGF...TSA...TOP...ICT...OUN...GID...DDC...

LAT...LON   38609970 39729868 40029820 39939763 39429765 38699703
            37929532 36919363 36299303 35819278 35479323 35659455
            36549694 37569886 37999960 38609970

Mesoscale Discussions in Kansas, 2021Mesoscale Discussions in Oklahoma, 2021Mesoscale Discussions in Arkansas, 2021Every mesoscale discussion in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.