Areas affected…northeast CO…southwest NE and northwest KS
Concerning…Severe potential…Severe Thunderstorm Watch likely
Valid 171934Z – 172130Z
Probability of Watch Issuance…80 percent
SUMMARY…Thunderstorms capable of strong, damaging gusts and hail
will increase in the coverage through the afternoon and shift
east/southeast through this evening.
DISCUSSION…Isolated thunderstorms were developing this afternoon
near the higher terrain of north-central CO as a subtle shortwave
impulse ejects across the area. Surface dewpoints increase from
meager 30s F near the I-25 corridor to the mid 60s just east of the
CO/NE/KS tri-state area. Meanwhile, a plume of very steep midlevel
lapse rates reside across the region, resulting in MLCAPE values
increasing from around 500-1000 J/KG near the Palmer Divide to 2000
J/kg across parts of western into central KS/NE. With continued
destabilization, high-based convection is expected to increase in
coverage. On the southern fringes of strong deep-layer flow, bulk
shear values around 25-35 kt should help to sustain organized cells.
While steep lapse rates will support hail production, damaging wind
is also possible. Strong downdrafts/downward transport will be
supported by a deeply-mixed sub-cloud layer and light low level
winds. As such, a swath of damaging wind is possible across parts of
southwest NE/northeast CO/northwest KS this afternoon and evening. A
severe thunderstorm watch likely will be needed in the next couple
of hours.
..Leitman/Grams.. 08/17/2019
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…GID…LBF…GLD…PUB…BOU…CYS…
LAT…LON 41810257 41590190 41290117 40560005 39859982 39270012
38800069 38750159 38840297 38950425 39200460 39870475
41060437 41620408 41830353 41810257