April 26-May 1 Plains/MW/OV Severe Weather, SPC Risk Level: Day 1 Slight Risk Forecasts and OBS Options

[jdrenken]

12Z NMM

[Gcode3000]

700mb temps are pushing 11C as far North as Independence, KS. Gonna need more moxie to break the cap.

Ha, I'm in Independence. Very windy now and it has that feel of instability. They have the highest risk of severe weather just to my North as you know but I will be keeping a close eye on the conditions. The Weather channel has had us with a minimal possibilty for severe weather until all of a sudden they issue a tor con 8 for us.

This post has been edited by Gcode3000: Apr 27 2012, 02:00 PM

[jdrenken]

Mid-Level Lapse Rates of 8.5 stretching almost to Topeka.

[jdrenken]

Ha, I'm in Independence. Very windy now and it has that feel of instability. They have the highest risk of severe weather just to my North as you know but I will be keeping a close eye on the conditions. The Weather channel has had us with a minimal possibilty for severe weather until all of a sudden they issue a tor con 8 for us.

I was talking with some friends of mine that as a chase starting point, Independence would be a great base to watch the event unfold. Stay safe!

[WeatherMonger]

[WeatherMonger]

SEL4

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 194
NWS STORM PREDICTION CENTER NORMAN OK
215 PM CDT FRI APR 27 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

CENTRAL AND EASTERN KANSAS

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 215 PM UNTIL 900
PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 85 STATUTE
MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF CONCORDIA
KANSAS TO 50 MILES SOUTH SOUTHWEST OF CHANUTE KANSAS. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU4).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

DISCUSSION...STORMS ARE EXPECTED TO CONTINUE DEVELOPING ALONG THE
DRY LINE OVER CENTRAL KS IN RESPONSE TO INCREASING FORCING FROM A
STRONG VORTICITY MAX MOVING OVER WRN KS. HEATING IN ADVANCE OF THE
DRY LINE OVER CENTRAL INTO SOUTH CENTRAL KS IS CONTINUING TO
DESTABILIZE THE AIR MASS AND WEAKEN THE CAP...WITH RADAR AND VISIBLE
SATELLITE SHOWING EARLY STAGES OF DEEPENING CONVECTION. CURRENT
STRONG/SEVERE STORMS OVER NORTH CENTRAL KS WILL MOVE NEWD TOWARD
NERN KS...WHILE OTHER STORMS ARE EXPECTED TO INTENSIFY OVER SOUTH
CENTRAL/SERN KS. VAD AND WIND PROFILER DATA SUPPORT SUPERCELL
FORMATION WITH POTENTIAL FOR VERY LARGE HAIL...TORNADOES...AND
DAMAGING WIND GUSTS FROM STRONGER CELLS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 22035.


...WEISS

Note:  Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
Mod (50%)
Probability of 1 or more strong (F2-F5) tornadoes
Mod (30%)
Wind
Probability of 10 or more severe wind events
Mod (30%)
Probability of 1 or more wind events > 65 knots
Low (20%)
Hail
Probability of 10 or more severe hail events
Mod (60%)
Probability of 1 or more hailstones > 2 inches
Mod (30%)
Probability of 6 or more combined severe hail/wind events
High (80%)

This post has been edited by WeatherMonger: Apr 27 2012, 02:24 PM

[WeatherMonger]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0259 PM CDT FRI APR 27 2012

VALID 272000Z - 281200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER PART OF CENTRAL AND ERN KS
INTO WRN MO...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CENTRAL PLAINS INTO
THE LOWER MO VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN GA INTO SC...

...KS/WRN MO AND SERN NEB...
THE ADVANCEMENT OF THE DRY LINE INTO CENTRAL KS THIS AFTERNOON
SUPPORTS ADJUSTMENT EWD OF THE WRN PARTS OF THE SLIGHT AND MODERATE
RISK AREAS. IN ADDITION...GIVEN NEWD STORM MOTIONS WITH THE
ACTIVITY OVER NRN KS...A SMALL PART OF SERN NEB HAS BEEN ADDED TO
THE SLIGHT RISK AREA. IN THIS LATTER AREA...THE SEVERE THREAT WILL
BE PRIMARILY FOR HAIL AND STRONG WIND GUSTS AS THESE STORMS SHOULD
TEND TO REMAIN N OF GREATER MOISTURE/INSTABILITY AND N OF THE
SURFACE LOW/WARM FRONT.

DESPITE WHAT HAD BEEN A DELAY IN TSTM INITIATION WITH SWD EXTENT
ALONG THE DRY LINE...ACTIVITY IS EXPECTED TO CONTINUE DEVELOPING
THIS AFTERNOON INTO THE EVENING AS STRONGER FORCING FOR ASCENT
SPREADS ENEWD. THE PRESENCE OF MODERATE-STRONG INSTABILITY AND
EFFECTIVE BULK SHEAR UP TO 50 KT REMAINS SUFFICIENT TO MAINTAIN THE
MODERATE RISK FOR VERY LARGE HAIL...TORNADOES AND DAMAGING WINDS IN
THE STRONGER CELLS. FOR ADDITIONAL DETAILS...REFER TO WW 194 AND
ANY SUBSEQUENT WW/S AND MESOSCALE DISCUSSIONS.

...NERN GA INTO SC...
GIVEN THE PLACEMENT OF THE GENERALLY E-W ORIENTED SURFACE FRONT
EXTENDING FROM NRN SC WWD INTO FAR NRN GA/NRN AL AND ADDITIONAL
DESTABILIZATION WITH MLCAPE UP TO AT LEAST 1500 J/KG...CONVECTION
HAS BEGUN TO FORM ALONG AND S OF THE BOUNDARY. CONSEQUENTLY...THE
SLIGHT RISK AND SEVERE HAIL/WIND PROBABILITIES HAVE BEEN EXPANDED
NWD TO INCLUDE MORE OF NRN SC AND FAR NERN GA. THE AVAILABLE
INSTABILITY COMBINED WITH EFFECTIVE BULK SHEAR OF 30-40 KT WILL
SUPPORT ORGANIZED STORMS. FOR ADDITIONAL SHORT TERM MESOSCALE
DETAILS...PLEASE REFER TO MESOSCALE DISCUSSION 606.

..PETERS.. 04/27/2012

[The Snowman]

Moderate risk has caught my eye. Looks like some cells are developing along the western fringe of the watch box.

Live radar from PoliClimate.

Blue boxes: Severe t-storm warning
Red boxes: Tornado warning

[The Snowman]

RUC indicating what may happen in the next hour.

Attached thumbnail(s)

 

[WeatherMonger]

MESOSCALE DISCUSSION 0607
NWS STORM PREDICTION CENTER NORMAN OK
0344 PM CDT FRI APR 27 2012

AREAS AFFECTED...N-CNTRL/ERN KS

CONCERNING...TORNADO WATCH 194...

VALID 272044Z - 272145Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 194 CONTINUES.

LARGE HAIL THREAT CONTINUES AND TORNADIC POTENTIAL SHOULD INCREASE
/ESPECIALLY ALONG THE WARM FRONT NEAR THE I-70 CORRIDOR/...AS
SUPERCELL COVERAGE LIKELY INCREASES HERE IN THE NEXT FEW HOURS.
FARTHER S...SHOWERS HAVE STRUGGLED TO INTENSIFY ACROSS S-CNTRL KS
AND UNCERTAINTIES EXIST OVER THE SUSTAINABILITY OF SEVERE TSTMS WITH
SRN EXTENT.

20Z SURFACE ANALYSIS PLACED A 995 MB CYCLONE AROUND 40 N RSL WITH AN
ATTENDANT WARM FRONT EXTENDING SEWD TO NEAR EMP TO 20 E JLN...AND A
SURGING DRYLINE EXTENDING SWD NEAR ICT TO PNC. MOST PERSISTENT
CLUSTER OF TSTMS HAS PRODUCED SEVERE HAIL IN PORTIONS OF N-CNTRL
KS...ALONG AND JUST N OF THE SURFACE FRONT. RELATIVELY GREATER HAIL
AND TORNADO POTENTIAL WILL EXIST ALONG THE FRONT AS ADDITIONAL
SURFACE-BASED CELLS LIKELY PROPAGATE WITHIN THIS ZONE...BEFORE
BECOMING INCREASINGLY ELEVATED WITH NRN EXTENT.

DISCRETE CELLS ALONG THE DRYLINE IN S-CNTRL KS HAVE STRUGGLED TO
INTENSIFY AS FORCED ASCENT TIED TO THE COMPACT NWRN KS/SWRN NEB
IMPULSE HAS REMAINED FARTHER N. MODIFIED 18Z LMN RAOB SUGGESTS THAT
ALTHOUGH MLCIN IS MINIMAL...LOW RH AOA 3000 FT AGL IS LIKELY
RESULTING IN SUBSTANTIAL ENTRAINMENT OF DRY AIR WITH MIXED-LAYER
PARCELS. STILL...WITH STRONG LOW-LEVEL CONVERGENCE ALONG THE DRYLINE
AND A COUPLE MORE HOURS OF BOUNDARY LAYER HEATING...ALONG WITH
WEAKENING LARGE-SCALE DESCENT AS THE KS/NEB IMPULSE DAMPENS...A CELL
OR TWO COULD BECOME SUSTAINED INTO SERN KS BY EARLY EVENING.

..GRAMS.. 04/27/2012


ATTN...WFO...SGF...EAX...TOP...ICT...GID...

LAT...LON 39769834 39859750 39589660 39099565 38089495 37489516
37219539 37119619 37489668 38419734 39509840 39769834

[WeatherMonger]

That tornado warning is getting some strong tight rotation just WNW of Aurora, KS.

[WeatherMonger]

That tornado warning is getting some strong tight rotation just WNW of Aurora, KS.

Next frame showed it a bit broader in rotation but still fairly strong.

[WeatherMonger]

That tornado warning is getting some strong tight rotation just WNW of Aurora, KS.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
452 PM CDT FRI APR 27 2012

..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..

0438 PM TORNADO 4 WNW AURORA 39.47N 97.61W
04/27/2012 CLOUD KS STORM CHASER

BRIEF TOUCHDOWN REPORTED.


&&

$$

WOLTERS

[WeatherMonger]

Thought they forgot the text for a moment

MESOSCALE DISCUSSION 0609
NWS STORM PREDICTION CENTER NORMAN OK
0700 PM CDT FRI APR 27 2012

AREAS AFFECTED...NERN KS INTO NWRN MO

CONCERNING...SEVERE POTENTIAL...WATCH NEEDED SOON

VALID 280000Z - 280030Z

ONGOING HAIL STORMS EXPECTED TO IMPACT NERN KS INTO NWRN MO.

..JEWELL.. 04/28/2012


ATTN...WFO...EAX...OAX...TOP...

LAT...LON 38619432 38989533 39729586 40039535 40149457 39689363
38969335 38679341 38589373 38619432

[jdrenken]

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 196
NWS STORM PREDICTION CENTER NORMAN OK
720 PM CDT FRI APR 27 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

NORTHEAST KANSAS
WEST CENTRAL AND NORTHWEST MISSOURI

EFFECTIVE THIS FRIDAY EVENING FROM 720 PM UNTIL 1100 PM CDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 60
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 35
STATUTE MILES EAST AND WEST OF A LINE FROM 15 MILES NORTH
NORTHWEST OF SAINT JOSEPH MISSOURI TO 50 MILES SOUTH SOUTHEAST OF
OLATHE KANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 194...WW 195...

DISCUSSION...ELEVATED SUSTAINED STORMS/SUPERCELLS POSING A RISK FOR
SVR HAIL WILL AFFECT THE LAWRENCE/KANSAS CITY/ST JOSEPH AREAS THIS
EVE AS NARROWING...ELEVATED TONGUE OF HIGH THETA-E AIR PIVOTS NE
ACROSS REGION ON SRN FRINGE OF EJECTING UPR IMPULSE IN SRN NEB.
DEAMPLIFICATION OF UPR DISTURBANCE...AND PERSISTENT WAA ATOP
SFC-BASED COOL DOME...SUGGEST THAT STORMS MAY PERSIST OVER WW AREA
INTO MID EVE.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 50
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 23035.


...CORFIDI

[WeatherMonger]

That storm in SW KS might need a tornado warning upgrade shortly

[WeatherMonger]

Not real organized, but definitely has some rotation going on

[Superstorm93]

Today was a welcomed bust.

1) Cloud deck never really cleared enough for the CAP to break in S-KS
2) Low-level winds died off quickly with the occluding low
3) Once cells did develop, they quickly outran the best BL instability and LL winds thus reducing any strong tornado threat to pretty much zero
4) Very, very narrow warm sectors with crumbling UL systems are to never be trusted

[snowlover2]

My sister in Junction City KS sent me this pic of the 1" hail they got tonight.

[snowrawrsnow]

Thankful for the bust. Most of that area's still recovering from the last outbreak.