Mid-Missouri Valley: Watch out!!!

[Guest]

Things are looking very volitale for later this afternoon through tonight across the mid-Missouri Valley.

A High risk of severe thunderstorms exists from southeast Nebraska into southern Iowa, extreme northeast Kansas and northern Missouri. If you live in the Omaha, Des Moines or Kansas City areas, today would be a day you would want to pay attention to the latest weather developments.

Surrounding the High risk, a moderate risk enocmpasses a good chunk of the plains.


http://www.spc.noaa.gov/products/outlook/day1otlk.html

[Guest]

Yep this is looking like a very dangerous situation developing out that way later today. Tornado, Wind and hail threats are all high.

You guys out that way please be careful (If chasing) and safe as well. Report in when possible.

[Anonymous]

Looks like some of the same areas that saw the tornadoes Saturday... also many flood warnings are in effect from SE Nebraska through Iowa and Illinois. Be careful all in the area.

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
250 PM CDT SUN MAY 23 2004

IAZ007-017-026>028-037>039-049-050-061-062-075-086-097-241100-
BLACK HAWK-BREMER-BUTLER-CERRO GORDO-DAVIS-FRANKLIN-GRUNDY-HARDIN-
JASPER-MAHASKA-MARSHALL-POWESHIEK-TAMA-WAPELLO-WORTH-
250 PM CDT SUN MAY 23 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE FAR EASTERN PART OF MID
IOWA...ALONG AND EAST OF A LINE FROM MASON CITY...TO MARSHALLTOWN...
TO OTTUMWA.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

A WIDESPREAD SIGNIFICANT SEVERE WEATHER EVENT IS EXPECTED MONDAY
AFTERNOON AND NIGHT ACROSS CENTRAL IOWA. THUNDERSTORMS ARE EXPECTED
TO DEVELOP DURING THE AFTERNOON HOURS ALONG AND NORTH OF A WARM
FRONT STRETCHING ACROSS SOUTHERN IOWA. SUPERCELL THUNDERSTORMS WITH
VERY LARGE HAIL AND DAMAGING STRAIGHT LINE WINDS ARE ANTICIPATED
DURING THE AFTERNOON INTO THE EARLY EVENING HOURS. A FEW STRONG
TORNADOES ARE ALSO POSSIBLE DURING THIS TIME FRAME. LATER MONDAY
EVENING...A THUNDERSTORM COMPLEX IS EXPECTED TO PROGRESS SOUTHEAST
THROUGH IOWA...WITH THE MAIN THREAT BECOMING DAMAGING STRAIGHT
LINE WINDS AFTER SUNSET. MANY LOCATIONS WILL RECEIVE AN INCH OR MORE
OF RAINFALL...WITH LOCALLY HIGHER AMOUNTS. FLASH FLOODING...THOUGH
NOT THE PRIMARY CONCERN...WILL BE POSSIBLE.  THE ADDITIONAL RAINS
WILL AGGRAVATE THE RIVER FLOODING SITUATION OVER CENTRAL IOWA.

THE NEXT BEST CHANCE OF THUNDERSTORMS IS FRIDAY AND FRIDAY NIGHT.

.SPOTTER ACTIVATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY MONDAY AFTERNOON AND NIGHT.


[/quote]

[USAwx1]

Check out this sounding from KMCI (kansas City, MO) VT 21z this afternoon./

################################

Sounding variables and indices
1000-500 mb thick: 5749.70 m
Freezing level: 607.38 mb = 4267.36 m = 14000.35 ft
Wetbulb zero: 678.76 mb = 3362.26 m = 11030.90 ft
Precipitable water: 1.37 inches
Sfc-500 mean rel hum: 66.36 %
Est. max temperature: 32.87 C = 91.16 F
Sfc-Lift cond lev (LCL): 871.30 mb = 1245.31 m = 4085.60 ft T: 21.00 C
700-500 lapse rate: 8.77 C/km
ThetaE index: 40.91 C Layer 950.0- 525.0 mb
Conv cond level (CCL): 821.68 mb = 1752.18 m = 5748.56 ft
Mean mixing ratio: 16.57 g/kg
Conv temperature: 32.84 C = 91.11 F
Cap Strength: 1.18 C
Lifted Index: -12.04 C Risk: Severe thunderstorms probable
Lifted Index @300 mb: -13.52 C
Lifted Index @700 mb: -1.66 C
Showalter Index: -7.29 C Risk: Severe thunderstorms probable
Total Totals Index: 60.14 C Risk: Severe Thunderstorms probable
Vertical Totals Index: 33.31 C
Cross Totals Index: 26.83 C
K Index: 27.64 Risk: 40-60 % chance of thunderstorms
Sweat Index: 641.79 Risk: Severe Thunderstorms possible
Energy Index: -4.02 Risk: Severe Thunderstorms probable

Parcel Indices
Parcel: using surface
CAPE (B+): 5653.96 J/kg
Max Up Vert Vel: 106.34 m/s
Conv Inhibition (B-): 0.00 J/kg
Cap Strength: 0.00 C
Lift Cond Lev (LCL): 871.30 mb = 1245.31 m = 4085.60 ft
Lev Free Conv (LFC): 866.30 mb = 1295.24 m = 4249.43 ft
Equ Level (EL): 146.30 mb = 14083.50 m = 46205.15 ft
B at Equ Level: 5594.26 J/kg
Max Parcel Lev (MPL): 66.30 mb = 19001.38 m = 62339.74 ft

######################################

Wind Parameters
Mean winds (0-6000m): 212.2 at 36.8 knts
Storm direction: 242.2 at 27.6 knts
Shear (0-3000m) pos: 6.2 neg: 0.0 tot: 6.2 10-3/s
Storm rel Dir Shear (0-3000m): 82.6 deg
Storm rel helicity (0-3000m) pos: 391.3 neg: 0.0 tot: 391.3 m^2/s^2
ave: 130.4 10^-3 m/s^2 rel: 0.80
Storm rel vorticity (0-3000m) horiz: 9.6 stream: 7.7 10^-3/s
Energy-Hel index: 12.60
Bulk Rich Number: 38.21
Bulk Shear: 147.98 m/s

####################################

With that kind of instability, dry air and high DD's at 700mb, mid level lapse rates of almost 9.0 DEG C/km, and great deep layer shear, things are going to get going in a hurry across the plains once the s/w kicks out of the 4-corners and LLJ intensifies in the later afternoon and evening.

heh...if nothing else those LI values of -12 and SWEAT indicies of almost 650 should get a rise out of some, or that even considering CAPE of over 5000 J/kg, BRN shear would still be strong enough (~150 m/s) to yield BRN numbers which are still within the acceptable range for suprecell formation.