Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS02 KWNS 221718
SPC AC 221717
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1217 PM CDT Wed Mar 22 2017
Valid 231200Z - 241200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM A PORTION OF
WESTERN TEXAS THROUGH EXTREME EASTERN COLORADO...WESTERN KANSAS AND
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER THE
SOUTHERN THROUGH CENTRAL HIGH PLAINS...
Thunderstorms will pose a threat for large hail, damaging wind gusts
and perhaps a couple of tornadoes in parts of the southern through
central High Plains Thursday evening.
...Central through southern High Plains region...
Upper trough approaching the CA coast as of mid day Wednesday will
reach the central and southern High Plains Thursday evening. Lee
cyclogenesis will commence early Wednesday, and the low will deepen
over eastern CO within exit region of an upper jet max rotating
through the base of the upper trough. The resulting strengthening
low-level jet will advect modified continental-polar air with middle
to upper 50s F dewpoints through the high plains beneath plume of
steep lapse rates contributing to 1000-1500 J/kg MLCAPE during the
afternoon. The atmosphere will likely remain capped most of the day.
However, storms should develop from eastern NM and CO into western
TX and KS by early evening as deep forcing for ascent accompanying
the progressive shortwave trough overtakes the sharpening dryline.
Strong 50+ kt sfc-6 km shear will support supercells with large hail
and isolated damaging wind the main threats. However, 0-1 km
hodograph size will increase during the early evening as the
low-level jet strengthens, suggesting at least a small window of
opportunity for a couple of tornadoes before the boundary layer
begins to stabilize. Additional storms may develop farther east
later Thursday night from west central through north central Texas,
but the thermodynamic environment is not expected to be sufficient
for a severe threat.