5/18/05: TALK: Central Plains

[mikegeukes]

Some storms have fired in northeast Kansas and northwest Missouri.
Golfball size was reported in the storm in Jefferson County KS

Updated Area Forecast Discussion from Wichita KS.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WICHITA KS
641 PM CDT WED MAY 18 2005

MESO UPDATE

STORMS ARE EXPECTED TO DEVELOP ALONG THE FRONTAL BOUNDARY SHORTLY AS THE CAP IS PRETTY MUCH ERODED DUE TO MID LEVEL COOLING ALOFT. STILL EXPECTING STRONG TO SEVERE STORMS TO MATERIALIZE AND MOVE EAST ACROSS SOUTHERN KS.

SPC Mesoscale Discussion
http://www.spc.noaa.gov/products/md/md0906.html

Mike

 

[Bobby Lang]

In Wichita, I have noticed a couple clouds building higher than I have seen all day. Still holding out hope one will break the cap. I am going to go grab something to eat, and then hopefully be ready to chase something .

For a "live" look, here are two images from my backyard.
[Broken External Image]:[URL]http://img282.echo.cx/img282/9159/cloud12kz.th.jpg[/url]
[Broken External Image]:[URL]http://img279.echo.cx/img279/2158/cloud21xx.th.jpg[/url]

 

[Sheila_Ward]

I am east of Wellington. I see some stuff trying to build a little north of me. Nothing else going on here right now, just sunshine.

 

[mikegeukes]

Since a few chasers are in the Andover. El Dorado, Wichita area,
I post the text data from the RUC forecast sounding for Wichita

RUC Forecast Sounding for Wichita KS
valid 01Z THU 19 MAY 05

Sounding variables and indices
1000-500 mb thick: 5737.33 m
Freezing level: 595.72 mb = 4405.45 m = 14453.41 ft
Wetbulb zero: 666.34 mb = 3495.45 m = 11467.86 ft
Precipitable water: 1.41 inches
Sfc-500 mean rel hum: 61.45 %
Est. max temperature: 28.17 C = 82.70 F
Sfc-Lift cond lev (LCL): 911.24 mb = 862.64 m = 2830.15 ft T: 21.67 C
700-500 lapse rate: 6.34 C/km
ThetaE index: 19.21 C Layer 900.0- 650.0 mb
Conv cond level (CCL): 828.12 mb = 1684.36 m = 5526.06 ft
Mean mixing ratio: 13.17 g/kg
Conv temperature: 27.61 C = 81.69 F
Cap Strength: 0.97 C
Lifted Index: -2.99 C Risk: Severe thunderstorms possible
Lifted Index @300 mb: -4.72 C
Lifted Index @700 mb: -0.23 C
Showalter Index: -2.28 C Risk: Severe thunderstorms possible
Total Totals Index: 49.24 C Risk: Scattered heavy thunderstorms
Vertical Totals Index: 25.76 C
Cross Totals Index: 23.49 C
K Index: 27.93 Risk: 40-60 % chance of thunderstorms
Sweat Index: 217.57 Risk: None
Energy Index: -2.15 Risk: Severe Thunderstorms probable

Parcel Indices
Parcel: using 100 mb layer
CAPE (B+): 1101.78 J/kg
Max Up Vert Vel: 46.94 m/s
Conv Inhibition (B-): 17.76 J/kg
Cap Strength: 0.97 C
Lift Cond Lev (LCL): 847.81 mb = 1484.84 m = 4871.45 ft
Lev Free Conv (LFC): 802.81 mb = 1948.05 m = 6391.15 ft
Equ Level (EL): 192.81 mb = 12415.52 m = 40732.85 ft
B at Equ Level: 1086.44 J/kg
Max Parcel Lev (MPL): 122.81 mb = 15191.56 m = 49840.46 ft

Wind level data
Storm motion: 299 at 12 knt

Wind Parameters
Mean winds (0-6000m): 269.3 at 15.8 knts
Storm direction: 299.3 at 11.8 knts
Shear (0-3000m) pos: 2.4 neg: 0.7 tot: 3.1 10-3/s
Storm rel Dir Shear (0-3000m): 112.2 deg
Storm rel helicity (0-3000m) pos: 74.9 neg: 0.0 tot: 74.9 m^2/s^2
ave: 25.0 10^-3 m/s^2 rel: 0.67
Storm rel vorticity (0-3000m) horiz: 5.5 stream: 3.6 10^-3/s
Energy-Hel index: 0.47
Bulk Rich Number: 24.34
Bulk Shear: 45.26 m/s

Mike

 

[Scott Lincoln]

Surprise tornado touchdown in Iowa....
Spotter indicated tornado warning for Webster County... Fort Dodge, Iowa area....

No other warnings in iowa at this time, but a few storms are forming. With some shear in place, any storms that can become surface based should have the possibility of producing these shortlived landspout tornadoes, but I definitely wouldn't expect anything widespread since we had no sun at all today.

 

[Mike Johnston]

Series of isolated cells just firing over past 10 minutes over S Central KS. Most rapid intensification appears to be cell between Marion and Cottonwood Falls, along Marion/Chase county line.

 

[mikegeukes]

Time: 0734 CDT, 1934, 0034 UTC
Storms are firing up in a line, attm there are isolated from Harper, Kingman, Sedgwick, Harvey, Marion, Chase, Lyon, Osage, Shawnee counties and also very weak echoes in Butler County. Source: NWS Wichita Radar

Mike

 

[mikegeukes]

Looking at the Local Storm Reports thru 805 CDT
5 tornadoes reported in Iowa (DMX)
3 tornadoes reported in Minnesota (MPX)

Mike

 

[Scott Lincoln]

Tornado warning extended into neighboring county for Iowa storm....
Spotters continue to indicate a large wall cloud with brief tornado spin-ups, including a chaser from Iowa State.

 

[Scott Lincoln]

Picture sent in to KCCI-tv, Des Moines, of the Iowa storm's tornado. Fairly decent sized for such a low-instability day. Looked to be just a bit larger than rope-sized.
Tornado was reported to have lasted for 10 minutes.
No damage so far.

 

[Mike Hollingshead]

I just left for a drive and could see those tiny storms from the NE side of the MO river. I hadn't looked at them on radar for a while or very often but knew they were small. I was amazed at how low the convection looked. It scared me right away because the convection looked like it was more or less on the ground. I can't think of any instance when viewing a tower from the west seeing the convection that low. The towers were barely even able to anvil though. I did look at some data early and noted the 50 knot core at 500mb over that area with 70+ approaching up at 300mb. So seeing them teared apart early in their height is not surprising. Certainly interesting. I chase about anything when it is so 'close' and didn't give much thought to chasing this day up here. Oh yes, I laughed when I read the earlier tornado report and looked at radar. That was before I headed out and saw the lowness of the convection.

 

[Mike Johnston]

Just received a report from Dick McGowan out in the field. He was near Osage City, KS aside a developing mesocyclone. Lightening hit power line about 50 yards away from him, and appeared to knock out power to Osage City. He is OK, but a little shaken.

 

[J Holder]

He went right by my house then! Power was out for abt 20 min.

NWS put another SVR warn for cell developing in Olivet area. Worst hail so far is nickel size at the Melvern outlet.


JH

 

[Scott Lincoln]

Todays tornado reports so far today:

Iowa: 10 (1 larger than rope-sized)
Minnesota: 3
Kansas/Oklahoma: 0

Today speaks the lesson of the Illinois outbreak last year. Sometimes all it takes is super-low LCLs and good shear. I am still not discounting the possibility of a tornado in Kansas still tonight, but they just dont seem to have the support for them.

 

[Kevin Walter]

Does it bother anyone else that the 12 hour RUC forecast from earlier today underforecast the dewpoints in northern OK by approximately 20 degrees?

It's interesting how the dewps have continued to rise all day in that area - I guess low clouds and cap didn't allow the moisture to mix out vertically as much. Couple that with all the chasers sitting in Wichita sweating with each passing hour without initiation...