Severe Thunderstorm Warning 53, NWS Kansas City, MO

NORTHWEST MISSOURI FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PLEASANT HILL/KANSAS CITY MO
245 PM CDT SAT MAY 17 1997

FAIRLY ACTIVE NEXT 36 HRS EXPECTED.  SVR WX THREAT IS FIRST AND
FOREMOST CONCERN.  FIRST SHORT WAVE TROF TO AFFECT FA NOW OVER NW KS
OR SO PER PROFILERS AND WV IMAGERY.  ETA MINORS THIS FEATURE OUT
SLIGHTLY TOWARD 00Z BUT STILL SEE ITS REFLECTION IN 700 & 500 HEIGHTS
BY 06Z WITH 700 VORT CENTERED OVER FAR NW MO.  CONSIDERABLE WAA
CLOUDINESS DVLPG AHD OF FEATURE IN CNTRL NEB/KS.  AT ANY RATE...DEPSITE
WK LOW LVL CONVERGENCE...LOOKS LIKE KS WAVE TO PROVIDE JUST ENUF UPWARD
FORCING TO OVERCOME EVER WEAKENING CAP.  QUICKIE MODIFIED 12Z TOP
SOUNDING USING 87/61 SFC PARCEL YIELDED AT LEAST 2000 J/KG CAPE AND
MINIMAL CAP.  THUS...EXPECTING TSRA TO FIRE PRIOR TO SUNSET WITH SVR A
PSBLTY.

BETTER SVR THREAT LOOKS TO BE TNGT AS MUCH STRONGER ALBERTA TROF DROPS
SE AND GENERATES NICE HEIGHT FALLS ACRS HI PLAINS.  ETA DVLPS 40KT
SWRLY LLJ IN RESPONSE BY MIDNIGHT WHICH BECOMES NEARLY PERPENDICULAR TO
DIFFUSE BUT CERTAIN BOUNDARY CURRENTLY LOCATED ROUGHLY FROM NCNTRL KS
TO SCNTRL MO (WITH ANOTHER BOUNDARY JUST SOUTH OF IA/MO BORDER). RESULT
IS PRETTY STRONG LIFT OF VERY UNSTALBE AIR OVER BOTH BOUNDARIES. ETA
QPF ALSO DEVELOPS CONVECTIVE PCPN ON NOSE OF LLJ IN ERN KS.
THEREFORE...EXPECT WILL GO ABV LOW GUIDANCE POPS...MAYBE INTO LIKELY
CATEGORY.  QUESTION WHETHER OR NOT TO MENTION SVR.  GET PRETTY GOOD
TURNING IN SUB-CLOUD LAYER TNGT...VERY UNSTABLE AIR IN PLACE AND LIFT
FROM SHORT WAVE PLUS HELP FROM BOUNDARY.  HOWEVER...MID-LEVEL WINDS
PRETTY WEAK SO ALTHO SHD BE ABLE TO GET UPDRAFTS SUSTAINED FOR A
REASONABLE AMOUNT OF TIME...TSRA SHOULD TRANSITION FAIRLY QUICKLY INTO
OUTFLOW DOMINATED CELLS.

JUST READ WELL-WRITTEN SWODY1 WITH UPGRADE FROM SLGT TO MDT RISK AND
THIS PUSHES ME OVER FENCE.  WILL MENTION SVR.

TMRW LOOKS TO BE ACTIVE AS WELL...PENDING LOCATION OF CONVECTIVE
BOUNDARIES OF TONIGHT.  UNLESS CONVECTIVE DEBRIS CLOUDS INHIBIT
HEATING...SHOULD WARM TO LEVELS VERY CLOSE OF THOSE TODAY (XCP POSSIBLY
IN THE NW WITH EARLIER FROPA) GIVEN FCST 850 MB TEMPS.  BELIEVE TSRA
SHD REFIRE FROM JUST SE OF MKC TO IRK LINE ALONG FRONT AND QUICKLY
BECOME SVR.  WILL HOLD OFF THOUGH ON MENTION OF 2ND PERIOD SVR GIVEN
QUESTION OF POSITION OF BOUNDARIES.  WILL ORIENT POPS FROM NW TO
SE...HIEST SE.  TEMPS WILL FOLLOW SIMILARLY.

PROXIMITY OF FRONT TO SERN ZONES WILL FORCE ME TO KEEP POPS IN FOR SUN
NIGHT...WHILE NW ZONES IN STG CAA WILL GO POP-FREE.

SPENT EXCEPTIONALLY LITTLE TIME LOOKING AT RETURN TO COOLER WX ON MON.
GUIDANCE TEMPS LOOK FINE.

MCI BB 065/085 054/066 044 99653

MANION