US Storm Chasing 2012

[03Stormchaser]

Early March Outbreak information - 57 Confirmed tornadoes including 10 EF3 ans 1 EF4:

http://en.wikipedia.org/wiki/Early_Marc ... o_outbreak

[Nev]

Interesting story about seismic signals detected from tornado...

'Tornadoes make the earth move'

(more graphics here)

[NZstorm]

You don't think of hail and coconut palms as occurring in the same place but a supercell thunderstorm with large hail occurred near Honolulu this morning! The 3inch hail is a record for the state.

[Tornado Tim]

They also had a bit of hail over the past few days as well, some stones in the example are very jagged.
March 6th Example:
Note: The video below does contain coarse language

[spwill]

Amazing weather for Hawaii, a tornado report as well.

[NZstorm]

The sounding for the area last night looks interesting with -16C at 500mb. Thats a nice upper cold pool for the tropics.

[NZstorm]

I found this chart interesting.

The average number of moderate risks issued each year over USA. Oklohoma looks the hot spot as far as SPC forecasting goes!

Note, a moderate risk in USA refers to a major outbreak of potentially destructive convective weather.

[NZstorm]

Interestingly the high risk average chart looks a bit different.

[Orion]

Interesting story about seismic signals detected from tornado...)

Thanks for that: fascinating....

[NZstorm]

Official report on that Hawaii hail a couple of weeks back. Interesting that you can get such severe convective weather over an oceanic Island. I haven't studied it but I'm guessing the spring jet stream would have impinged on the Islands weather.


RECORD EVENT REPORT...UPDATED
NATIONAL WEATHER SERVICE HONOLULU HI
910 AM HST THU MAR 22 2012

...NEW STATE RECORD HAILSTONE IN HAWAII...

NATIONAL WEATHER SERVICE PERSONNEL HAVE MEASURED A HAILSTONE
COLLECTED IN KANEOHE DURING THE SEVERE THUNDERSTORM ON THE MORNING
OF MARCH 9TH 2012. THE HAILSTONE HAD A LENGTH OF 4 AND ONE QUARTER
INCHES. ACCORDING TO HISTORICAL DATA THIS HAILSTONE SETS THE RECORD FOR THE
LARGEST HAILSTONE TO HAVE FALLEN IN HAWAII. THIS NEW RECORD HAS BEEN
OFFICIALLY CONFIRMED BY THE STATE CLIMATE EXTREMES COMMITTEE AND
WILL BE ADDED TO THE RECORD BOOK IN THE ARCHIVES OF THE NATIONAL
CLIMATIC DATA CENTER.

[NZstorm]

With the mild winter and early spring in USA, makes me think its May now on the weather clock.
Could be that the jet stream disappears into Canada earlier this year, but I could be wrong.

Some big instability numbers there tomorrow but the 500mb flow is southerly which is not that favourable.

[Willoughby]

Good footage here from Dallas, TX: http://www.stuff.co.nz/world/americas/6 ... s-twisters

http://thescoopblog.dallasnews.com/arch ... ather.html

[Manukau heads obs]

http://www.stuff.co.nz/world/americas/6 ... s-twisters

good to see people stopping on the freeway...

[Orion]

A short video:

http://content.usatoday.com/communities ... 3uxC_Cn-Vp

and some chilling pictures:

http://www.buzzfeed.com/mjs538/incredib ... ear-dallas

[03Stormchaser]

Amazing stuff today, was streaming it on my phone at work!

[NZstorm]

I was watching the live stream myself this morning. Problem is you can waste a lot of time watching this stuff!

The system didn't produce yesterday but picked up moisture and shear as it came east. Often you get that in April.

[jamie]

email from Roger Hill stating how good thurs fri sat sun look over there next week in oklahoma and kansas. wish i had the cash to head over.

[03Stormchaser]

http://www.liveleak.com/view?i=610_1334095492
Video, tornado hits St. louis airport. Very lucky people!

[NZstorm]

Looks very active for tornado alley this weekend.

[Willoughby]

Not very often will you see a Moderate risk being forecast three days out!

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0234 AM CDT THU APR 12 2012
...

...SRN AND CENTRAL PLAINS...
WEAK HEIGHT FALLS ARE EXPECTED ACROSS THE SRN/CENTRAL PLAINS THROUGH
SAT AFTERNOON...WITH STRONGER FALLS FORECAST FOR SAT
EVENING/OVERNIGHT AS THE PACIFIC TROUGH MOVES TOWARD THE SRN AND
CENTRAL HIGH PLAINS. STRONG SLY LOW LEVEL WINDS WILL MAINTAIN
MOISTURE ADVECTION E OF THE DRY LINE ON SAT WITH SURFACE DEWPOINTS
IN THE MID 60S EXPECTED ACROSS MUCH OF OK AND REACHING CENTRAL/ERN
KS BY SAT EVENING. THIS MOISTURE RETURN COUPLED WITH STEEP MIDLEVEL
LAPSE RATES AND STRONG SURFACE HEATING /ESPECIALLY NEAR THE DRY
LINE/ WILL RESULT IN MODERATE TO STRONG INSTABILITY /MLCAPE
2000-2500 J PER KG/ ACROSS THE MODERATE RISK AREA BY LATE AFTERNOON
AND THE SURROUNDING SLIGHT RISK. STRENGTHENING DEEP LAYER WIND
FIELDS...VEERING WITH HEIGHT...WILL RESULT IN STRONG EFFECTIVE BULK
SHEAR /EXCEEDING 50 KT/ AND ORIENTED ACROSS THE DRY LINE. THIS
COMBINED WITH INCREASING LOW LEVEL HODOGRAPH CURVATURE WILL SUPPORT
TORNADIC SUPERCELLS AND THE POTENTIAL FOR VERY LARGE HAIL AND
DAMAGING WINDS. THESE FACTORS COMBINED WITH FAST STORM MOTIONS
SUGGEST THE POTENTIAL FOR LONG-TRACKED...STRONG TORNADOES OCCURRING
FROM THE AFTERNOON THROUGH THE EVENING /INCLUDING AFTER DARK/.

[Tornado Tim]

A significant Tornado outbreak is being predicted in central Oklahoma and Kansas, SPC going for 60% risk of Severe Weather occurring in the area!
High Risk is now in place 2 days out,strong wording is used in the bulletin to ensure residents in this area take this event seriously.

AN IMPRESSIVE UPPER-LEVEL LOW WILL MOVE EWD ACROSS FOUR CORNERS
REGION SATURDAY AS A POWERFUL 90 TO 110 KT MID-LEVEL JET EJECTS NEWD
INTO THE SRN AND CNTRL PLAINS. AHEAD OF THE SYSTEM...A CORRIDOR OF
MODERATE TO STRONG INSTABILITY IS FORECAST ACROSS ECNTRL KS...CNTRL
OK INTO NW TX. THIS COMBINED WITH STEEP MID-LEVEL LAPSE RATES AND
STRONG LOW-LEVEL SHEAR WILL BE VERY FAVORABLE FOR SEVERE STORMS AND
A TORNADO OUTBREAK WILL BE LIKELY ACROSS THE SRN AND CNTRL PLAINS
FROM LATE SATURDAY AFTERNOON LASTING THROUGH THE EVENING AND INTO
THE OVERNIGHT PERIOD.

NAM AND NAMKF FORECAST SOUNDINGS AT 00Z SATURDAY EVENING FROM SALINA
KS SWD TO AROUND OKLAHOMA CITY SHOW MLCAPE VALUES FROM 2000 TO 3000
J/KG WITH 0-6 KM SHEAR IN THE 60 TO 75 KT RANGE. IN
ADDITION...HODOGRAPHS ARE LARGE AND LOOPED WITH 0-1 KM SHEAR VALUES
IN THE 30 TO 40 KT RANGE. THIS ENVIRONMENT SHOULD BE VERY FAVORABLE
FOR SUPERCELLS AND TORNADOES. 0-3 KM STORM RELATIVE HELICITIES ARE
FORECAST TO BE AROUND 400 M2/S2 WHICH IS IDEAL FOR STRONG TORNADOES
AND A TORNADO OUTBREAK APPEARS LIKELY. THE GREATEST THREAT FOR
SIGNIFICANT TORNADOES SHOULD EXIST SATURDAY EVENING FROM SALINA SWD
TO OKLAHOMA CITY. 700 TO 500 MB LAPSE RATES AROUND 7.5 C/KM WILL
ALSO BE FAVORABLE FOR LARGE HAIL AND HAIL GREATER THAN 2 INCHES WILL
BE POSSIBLE THE MORE INTENSE SUPERCELLS. A WIND DAMAGE THREAT WILL
ALSO EXIST DUE TO THE EXPECTED INTENSE NATURE OF THE STORMS.

THE MAIN CONCERN FOR THIS FORECAST IS CONVECTIVE COVERAGE. MANY OF
THE MODELS DO NOT DEVELOP NUMEROUS THUNDERSTORMS ALONG THE DRYLINE.
IN SPITE OF THIS...THE MODELS DIMINISH THE CAP ACROSS THE SRN AND
CNTRL PLAINS LATE SATURDAY AFTERNOON SO THIS BRINGS THE MODELS INTO
QUESTION. IN ADDITION...THE MODELS DRIVE A BAND OF LARGE-SCALE
ASCENT ACROSS CNTRL KS DURING THE EARLY EVENING SUGGESTING MANY
STORMS SHOULD INITIATE WITH STORMS INITIATING SWD WITH TIME EARLY
SATURDAY EVENING AS THE LOW-LEVEL JET STRENGTHENS. THESE FACTORS
COMBINED WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F AND VERY
FAVORABLE LOW-LEVEL SHEAR PROFILES SHOULD PRODUCE AND ENVIRONMENT
FAVORABLE FOR A TORNADO OUTBREAK. AFTER COLLABORATION WITH WFOS
WICHITA...NORMAN...TOPEKA...TULSA AND DODGE CITY...A HIGH RISK WILL
BE ISSUED DUE TO THE POTENTIAL FOR A HIGH-END LIFE THREATENING EVENT
ACROSS THE SRN AND CNTRL PLAINS.

[03Stormchaser]

I think there will be a lot of chasers out over the next couple days!

[jamie]

Yup will be chasers convergence there. Traffic jams are becoming a problem in ok due to storm chasers. Hope it isn't a problem with a setup like this. However I can see thousands of people will chase this. It's the weekend too which will not help. Lots of locals will have a play

[Willoughby]

From the SPC's Facebook page:

Did you know that this is only the second time a high risk has been issued for the D2 forecast, and the first time ever it has been issued for the initial D2 outlook? The previous D2 high risk issuance was for the April 7, 2006 outbreak. Reports for that particular day can be seen here: http://www.spc.noaa.gov/climo/reports/060407_rpts.html

[NZstorm]

00Z forecast sounding for Grand Island, Nebraska according to NAM.