Severe Weather - May

[SB Shock]

First inkling of severe weather in the plains states is being shown in the models. Here is today SPC long range prediction.

BY SUN/D5...THERE IS STRONG EVIDENCE THAT A LARGE UPPER TROUGH WILL BEGIN TO TAKE SHAPE ACROSS THE WRN STATES WITH AN 80+ KT MID LEVEL JET DIGGING SWD ALONG THE W COAST. THE BOUQUET OF MREF SOLUTIONS AS WELL AS DETERMINISTIC MODELS SHOW LITTLE AGREEMENT ON D5 WITH HOW QUICKLY AND HOW FAR S THIS TROUGH WILL DEVELOP. THIS WILL HAVE AN IMPACT ON THE PROBABILITY OF SEVERE CONVECTION OVER THE SRN/CNTRL

HIGH PLAINS NEAR THE DRYLINE WHERE CAPPING WILL BE A CONCERN...AND ALSO WITH POSSIBLE NOCTURNAL CONVECTION FOCUSED OVER NEB/IA/MO/IL OVERNIGHT WITH A SWLY LOW LEVEL JET. BOTH THESE AREAS HAVE POTENTIAL...BUT NOT ENOUGH TO INTRODUCE ANY SEVERE AREAS WITH SUCH UNCERTAINTY.

FOR THE REMAINDER OF THE PERIOD MON/D6 TO WED/D8...THERE WILL LIKELY BE A SEVERE THREAT EACH DAY ALONG THE DRYLINE ACROSS THE CNTRL/SRN PLAINS...AND PERHAPS EXTENDING EWD FROM A SURFACE LOW/WARM FRONT ACROSS THE MIDWESTERN REGION AS THE UPPER TROUGH...AND/OR PIECES OF THE TROUGH EMERGE OVER THE REGION.

SEVERE AREAS BEGINNING SUN/MAY 8TH AND LASTING THROUGH ABOUT MAY 10TH ARE LIKELY FORTHCOMING FOR MUCH OF THE CNTRL U.S. AS THE EVENT NEARS AND PREDICTABILITY INCREASES.

[ShockerFever]

Judging by the way this storm season's gone so far, I wouldn't put too much stock into something a day out, much less a week out.

But I guess with such a lack of activity, anything at all looks enticing.

[Kung Wu]

Re: Severe Weather - May

NOCTURNAL CONVECTION

Finally, a scientific name for farting while asleep!

[wsushox1]

It's coming....Multi Days possible as well.

High Instability low shear potentially as well.

The 11 is a day too watch.

European Models still slower than the Global Forecasting System, makes a difference.

Upper level disturbance is really slow as it crosses the CONUS, allowing warm mid level temps to increase, Capping will be a concern early until the trough approaches and cools down the mid levels.

Those are my thoughts as they come into my head as of now.

These models are showing some messed up upper level flow, some regimes I have never seen before, so I am a little skeptical.

[EAGLE]

If we have bad storms the 11th (my birthday) some one is going to be in trouble. :yes: :yes: :yes: :roll: :roll: :roll:

[SB Shock]

SPC now putting risk areas up for Day 4 through 8

TUE AND WED APPEAR TO HAVE A
GREATER TORNADO THREAT THAN ON SUN/MON WITH HIGHER THETA-E AIR AND BETTER HODOGRAPHS

Here is the graphic. Note this is time sensitive and will be changing daily.

[wsushox1]

May 10 again this year? Shear is not going to be anywhere remotely close, but Instability is insane as lapse rates throughout the entire atmosphere are dry adiabatic.

[wsushox1]

Nothing to see here with anything,

Maybe hailers /prolific rainers and some wind gusts.......

But even that may be a stretch.

[ShockBand]

I'll take the prolific rainers, happily. The rest I can do without.

[SB Shock]

I hope this is not what we are in for this summer with a big ridge and record temps starting in may. This looked like a active weak with at least some good chances for rain but those chances seem to be dissipating quickly.

[wsushox1]

Then tonights Model Run GFS goes out and shows a decent Tornado Threat for SC KS on Wednesday lol......

Reverse Jinx

[wsushox1]

30% Hatched Day 3 Severe Probs out for SC KS all the way through OK and event N texas.

Classic dryline setting up, directional shear could be a it better, but as of now a severe event on Wednesday is looking likely.




From ICT the original Text below has been Edited:

WEDNESDAY-SUNDAY: MAIN CHALLENGE DURING THIS PERIOD OF THE
FORECAST IS CONVECTION. WITH THE SLOWER EVOLUTION OF THIS
SYSTEM...THERE ARE A FEW PROBLEMS EVOLVING: /1/ HOW WARM WILL IT
GET BEFORE THE SYSTEM MOVES THROUGH? /2/ WILL THE SEVERE THREAT
SHIFT WEST? /3/ WHEN TO END THE PRECIPITATION FROM THE MAIN
FRONT? /4/ DIURNAL SHOWER ACTIVITY FROM THE UPPER LEVEL COLD CORE
ASSOCIATED WITH THE LOW.

.........


THE SECOND...THE SEVERE THREAT DOES SEEM TO BE SHIFTING
WEST...WITH CONVECTION DEVELOPING OVER CENTRAL/SOUTH CENTRAL
KANSAS AND MOVING EAST. CAPE/SHEAR PROFILES STILL LOOK FAVORABLE
FOR SEVERE WINDS/HAIL. TORNADOES LOOK FAVORABLE AS WELL WITH 0-3KM
MLCAPES ABOVE 150 J/KG.

..........

STORM MOTION SHOULD BE NORTHEAST AT 25-30 MPH.

Source: http://forecast.weather.gov/product....n=1&glossary=1

[wsushox1]

Day 2 Moderate risk, Includes Wichita.

Image will be changing.

SPC AC 100543

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1243 AM CDT TUE MAY 10 2011

VALID 111200Z - 121200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER A PART OF CNTRL KS AND
CNTRL OK...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPR MS VLY SWD INTO
CNTRL TX...


....

STILL...BACKED NEAR SFC
FLOW VCNTY THE LEE LOW WILL BE FAVORABLE FOR SUPERCELLS WITH A FEW
TORNADOES AND LARGE HAIL. FARTHER S...MORE CROSS-COMPONENT DEEP
LAYER SHEAR VECTORS WILL RESULT IN LONGER-LIVED DISCRETE SUPERCELLS
ACROSS CNTRL/SCNTRL KS AND CNTRL OK WHERE VERY LARGE HAIL AND
TORNADOES WILL BE LIKELY.

[SB Shock]

looking at the probabilities, tomorrow has a chance to be a high risk day for parts of ks/ok. Wichita would likely be in the moderate risk area.

[wsushox1]

looking at the probabilities, tomorrow has a chance to be a high risk day for parts of ks/ok. Wichita would likely be in the moderate risk area.

Agreed, right now ICT has it nailed with this graphic...




The best directional shear is in the double shaded area and if the SPC goes high I expect that area to be it.

EDIT: The models are all over the map with this set up though so now it shows some of the better directional shear near Hutch ICT as opposed to the KS/OK border.

Overall though the upper level pattern is very ominious with a negative tilted trough interacting with a dryline that has an unstable airmass.