Virtual Storm Chase 3

[Nick F]

Today we see a deepening sfc low developing in the lee of the Rockies over the Sern High Plains.

-18z UTC (12z CDT)

... by 00z UTC Sat (18z) - the left exit region of a fairly strong flat jet streak lies over Nern OK ... and this is where today's severe threat and 5% chance of a tornado is - given the strong PVA forcing likely over this areas as the warm sector advances north over the area ahead of the sfc low.

DAY 1 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0718 AM CDT FRI MAR 14 2008

VALID 141300Z - 151200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF SRN KS/ERN OK

ACROSS THE MS/TN VALLEYS...

...SYNOPSIS...

BELT OF FAST ZONAL FLOW WILL CONTINUE FROM THE WEST COAST...ACROSS

THE MS VALLEY...TO THE SOUTHEAST THROUGH TODAY. LOW-AMPLITUDE SHORT

WAVE TROUGHS EMBEDDED WITHIN THIS FAST FLOW REGIME WILL INDUCE AREAS

OF STRONGER DEEP-LAYER ASCENT THAT WILL EITHER SUSTAIN ONGOING DEEP

CONVECTION...OR LEAD TO NEW CONVECTIVE DEVELOPMENT DURING THE

PERIOD.

...SRN PLAINS/OZARKS TO MS VALLEY TONIGHT/OVERNIGHT...

THE NEXT SHORT WAVE TROUGH WILL TAKE FORM OUT OF THE FAST MID/UPPER

LEVEL FLOW CROSSING THE FOUR CORNERS REGION AND GAIN SOME AMPLITUDE

OVER THE SRN PLAINS THROUGH TONIGHT. CONCENTRATED REGION OF MODEST

HEIGHT FALLS WITH THIS SYSTEM WILL CONTRIBUTE TO CYCLOGENESIS OVER

THE TX PANHANDLE LATER TODAY. SIMILAR TO THURSDAY NIGHT...LIFT AND

STEEP LAPSE RATES WITH THIS SYSTEM WILL COINCIDE WITH LOW LEVEL

MOIST AXIS...AND RESIDUAL DIURNAL HEATING...TO BRING AN INCREASING

CHANCE OF STRONG TO SEVERE TSTM DEVELOPMENT ACROSS PORTIONS OF

KS/MO/OK/AR THROUGH THIS EVENING AND OVERNIGHT.

AIR PARCEL TRAJECTORIES ARE FORECAST TO REACH A RELATIVELY HIGH LFC

AROUND 700MB AND CONTRIBUTE TO RAPID CONVECTIVE INITIATION ALONG AND

NORTH OF THE SURFACE LOW TRACK AND DEVELOPING WARM FRONT...FROM NWRN

OK/CNTRL KS TO NERN OK AND SWRN MO THROUGH LATE EVENING. WARM AND

MARGINALLY MOIST BOUNDARY LAYER ACROSS THESE AREAS WILL RESULT IN

MLCAPE AOB 1000 J/KG. THIS INSTABILITY SHOULD PROVE MORE THAN

ADEQUATE FOR SEVERE STORM FORMATION GIVEN MAGNITUDE OF LAPSE RATES

AND POTENT SHEAR EXPECTED. PRONOUNCED TURNING/HELICITY IN THE NEAR

SURFACE UPDRAFT LAYER IS DEPICTED IN FORECAST WIND PROFILES FROM

KS/OK BORDER EWD TO OZARKS. GIVEN RELATIVELY DRY BOUNDARY

LAYER...INITIAL STORMS MAY ACQUIRE LP-SUPERCELL CHARACTERISTICS WITH

ATTENDANT THREATS OF LARGE HAIL AND STRONG OUTFLOW WINDS.

CONVECTION SHOULD CONSOLIDATE INTO AN MCS OR TWO THROUGH LATE

TONIGHT AS THE DEEPENING CYCLONE TRACKS EAST ALONG THE INTENSIFYING

WARM FRONT FROM KS/OK TO THE OZARKS. DAMAGING WIND AND SEVERE HAIL

THREAT MAY INCREASE THROUGH THE NIGHT AS CONVECTION TAPS LOW LEVEL

MOIST AXIS FROM THE ARKLATEX TO THE MS VALLEY. DEEP-LAYER WLY FLOW

OF 40-60KT NOSING INTO AND BECOMING COINCIDENT WITH THE MCS WILL

FURTHER SUPPORT FAST MOVING STORMS...OR A COMPLEX OF STORMS...WITH

AN ENHANCED POTENTIAL FOR DAMAGING WINDS DEVELOPING AS FAR EAST AS

WRN TN/MS THROUGH DAYBREAK SATURDAY.

Unfortunately it may well time to be an overnight risk in the end - but chance IMO in the late afternoon perhaps of some LP or classic supercells kicking off further west than the tornado risk area towards the OK Panhandle - therefore I fancy starting in Woodward, OK then probably a trek eastwards towards Enid/Stillwater areas of north/central OK to follow the storms

[Nick F]

Early next week still looking good for a severe event over the Sern Plains:

DAY 4-8 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0358 AM CDT FRI MAR 14 2008

VALID 171200Z - 221200Z

...DISCUSSION...

THE PRIMARY FEATURE OF INTEREST DURING THE EXTENDED FORECAST PERIOD

WILL BE UPPER LOW WHICH WILL MOVE THROUGH THE SRN ROCKIES...SRN

PLAINS AND NRN MEXICO ON DAYS 4 AND 5 /MON AND TUE/. THE GFS

REMAINS MORE PROGRESSIVE IN THE EWD/NEWD MOVEMENT OF THIS LOW WHEN

COMPARED TO BOTH THE ECMWF AND UKMET. DESPITE THIS DIFFERENCE...IT

APPEARS THAT A MOIST AND UNSTABLE AIR MASS WILL BE COLOCATED WITH

STRONG VERTICAL SHEAR OVER A FAIRLY SIZABLE WARM SECTOR ON DAY 4

WITH AN ORGANIZED SEVERE WEATHER EPISODE POSSIBLE.

THIS SEVERE WEATHER THREAT SHOULD CONTINUE INTO AT LEAST DAY 5 OVER

ERN PARTS OF THE SRN PLAINS INTO LOWER MS VALLEY. THE POTENTIAL FOR

SEVERE WEATHER MAY CONTINUE INTO DAY 6 /WED/...THE EXTENT OF WHICH

REMAINS QUITE UNCERTAIN GIVEN THE MODEL DIFFERENCES IN THE HANDLING

OF THE UPPER TROUGH.

All kicks off later on Monday over TX and SernWern OK by the looks of it:

[Paul Sherman]

Going on Models will pick Weatherford (Ok) along the I40, So a Bit further South than you Nick, but that whole area of Woodward - Clinton - Weatherford could see some discrete Supercells fire ahead of the Surface Low.

Mondays Target has to be Shamrock, so after today Virtual Chase I will be having 2 full days of Guiness Chasing!

[Cookie]

thanks for the updates

One reported tornado yesterday in Pushmataha SE Oklahoma, no detail

on the size/path and duration.

Today sees a slight risk with 5% chance of tornadic activity.

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

There were 1 Tornado Reports Yesterday*| Today | Storms | Hail | Wind

Time (Z) Strength Location County State Lat Lon Comments

0338 UNK 6 NE RATTAN PUSHMATAHA OK 34.26 -95.34 BELOW

SPOTTERS ON HWY 3 REPORTED A TORNADO TOUCHDOWN 6NE OF RATTAN (TSA)

http://www.weathermatrix.net/stormmatrix/tornado/yesterday/

[Paul Sherman]

MD Issued for Me and Nick's Target Area's, both Weatherford and Woodward covered, should just about explode soon!

MESOSCALE DISCUSSION 0400

NWS STORM PREDICTION CENTER NORMAN OK

0323 PM CDT FRI MAR 14 2008

AREAS AFFECTED...PORTIONS WRN/NRN/CENTRAL OK...SWRN/S-CENTRAL

KS...E-CENTRAL/NERN TX PANHANDLE.

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 142023Z - 142300Z

TSTM POTENTIAL IS FCST TO INCREASE AND MOVE EWD THROUGH REMAINDER

AFTERNOON ACROSS DISCUSSION AREA -- HIGH-BASED...WITH LARGE HAIL AND

ISOLATED STG-SVR GUSTS POSSIBLE.

MOISTURE CHANNEL IMAGERY AND VWP/PROFILER WINDS INDICATE SHORTWAVE

TROUGH MOVING OUT OF S-CENTRAL ROCKIES AND ACROSS PORTIONS S-CENTRAL

HIGH PLAINS. ASSOCIATED STG/COMPACT PLUME OF LARGE SCALE ASCENT IS

SHIFTING EWD ACROSS TX PANHANDLE...ACCOMPANIED BY VERY HIGH BASED

CONVECTION. SFC MESOANALYSIS SHOWS CYCLONE INVOF NERN CORNER TX

PANHANDLE...FCST TO MOVE EWD ACROSS NWRN OK THROUGH LATE AFTERNOON.

DIFFUSE WARM FRONT SEWD ACROSS SERN OK SHOULD LIFT NWD OVER PORTIONS

CENTRAL/NRN OK. CONVECTION INITIALLY DEVELOPING ATOP VERY DRY SFC

AIR OF PANHANDLES AND SWRN KS -- E.G. DEW POINTS 20S F -- MAY MOVE

EWD PAST SFC LOW AND INTO WARMER AND SOMEWHAT MORE MOIST AIR...WITH

DEW POINTS MID-UPPER 30S. MORE BACKED/SLY AND SELY SFC WINDS WILL

ACCOMPANY PRESSURE FALLS NEAR AND N OF WARM FRONT. THIS REGIME WILL

RESULT IN INCREASE OF BOUNDARY LAYER THETAE...STORM-RELATIVE INFLOW

AND DEEP-LAYER SHEAR AVAILABLE TO ANY ACTIVITY MOVING EWD FROM

PANHANDLES. MODIFIED RUC SOUNDINGS SUGGEST VERY STEEP LOW-MIDDLE

LEVEL LAPSE RATES AROUND 9 DEG C/KM...AND SFC BASED LIFTED PARCELS

BETWEEN NOW AND ABOUT 01Z..SUPPORTING ABOUT 500 J/KG MLCAPE. 40-50

KT EFFECTIVE SHEAR AND 0-6 KM SHEAR UP TO 65 KT ALREADY ARE EVIDENT

OVER REGION PER VICI PROFILER.

SHEAR PROFILES WILL SUPPORT SUPERCELL AND SMALL BOW

STRUCTURES...WITH POTENTIAL FOR HAIL/WIND GIVEN DEEP/WELL-MIXED

SUBCLOUD LAYER. MOMENTUM FROM VERY STG AMBIENT/GRADIENT FLOW ALOFT

MAY BE BROUGHT TO SFC IN MORE VIGOROUS DOWNDRAFTS.

[Nick F]

Some nice little cells firing just south of Alva/east of Woodward now - possibly some LP supercells. Will be getting dark soon I presume though. Hail and strong wind gusts only likely from these cells as they are probably high based for now:

[Paul Sherman]

1 Hour 45 Minutes until Sunset Nick ?? :lol:

You Slacker!!

[Nick F]

Lol, although its 17.52 CDT there as I type - guess it gets dark later there than here then atm for the same time. I'm chasing those cells south of Alva right now in the clear slot you can see in the visible sat above (if I can see the visible sat images it can't be getting dark yet!)

Few of the guys on stormtrack following those storms over NW OK east of Woodward right now ... nothing particularly severe yet - they are high-based too:

http://www.stormtrack.org/forum/showthread...0197#post170197

[Cookie]

thanks for the link nick :lol:

[Gorky]

From reports, it appears as either a weak tornado or strong thunderstorm winds have hit Downtown Atlanta doing some damage to a stadium whilst a basketball game was being televised! No reports of injuries and only minor damage in the stadium, but some reports of injuries from blown out windows on nearby buildings. There was a very good couplet over the downtown area so I'd imagine a tornado was the most likely cause. The cell is still looking good with a nice hook:

There is a lot of activity in AR/LA at the moment with a few confirmed spotter reported tornados on the ground also. It's taken a while to get going but things are spinnning nicely at the moment.

[NL]

An upgrade to a moderate risk for today.

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

[NL]

Footage from that basketball game in the Atlanta Dome, luckily it was

a weak tornado as many people would have been injured or killed.

http://www.youtube.com/watch?v=7TT013NsSYc

[Nick F]

Awesome, shows that even everyday things we take for granted far removed from nature such as a game inside a building in a large metropolis such as Atlanta are vunerable to severe weather they have in the states. Bet there were a few concerned people in the stadium - despite the tornado being weak. If it was a strong tornado it would've probably peeled off the top of the dome!

Noticed there is a SLGT out for the Sern Plains for Monday - high based storms to begin with - but as the cold front moves in from the west - we should see some sfc based supercells develop later in the day - probably merging into a squall line moving east/ne. Wouldn't be suprised if they upgrade to MDT.

Today's MDT risk should be interesting to watch develop later today - Altanta is again at risk being in the MDT area - a 15% risk of a tornado over nern Georgia and the N and W of South Carolina ...

[Paul Sherman]

Oh what would we give for this to be 6-8 weeks down the Line Lovely Set Up with the Triple Point coming into Play!

...SRN PLAINS...

A STRONG...SLY LLJ WILL BE MAINTAINED AHEAD OF UPPER TROUGH WHICH

WILL ENHANCE THE NWD TRANSPORT OF AN INCREASINGLY MOIST AIR MASS

WITH DEWPOINTS INCREASING THROUGH THE 60S AHEAD OF DRYLINE/PACIFIC

COLD FRONT AND S OF RETREATING WARM FRONT. THIS MOISTURE COUPLED

WITH STEEP MIDLEVEL LAPSE RATES IS EXPECTED TO CONTRIBUTE TO A

MODERATELY UNSTABLE AIR MASS OVER PORTIONS OF OK SWD INTO CNTRL TX.

TSTMS /MAINLY ELEVATED/ ARE FORECAST TO EXPAND IN COVERAGE MONDAY

MORNING N OF RETREATING WARM FRONT OVER OK EVENTUALLY INTO ERN KS

AND MO ALONG NOSE OF LLJ. THE STEEP LAPSE RATES AND RELATIVELY

STRONG CLOUD BEARING SHEAR SHOULD SUPPORT ORGANIZED/SUSTAINED

UPDRAFTS WITH A THREAT OF LARGE HAIL. MORE ROBUST...SURFACE-BASED

TSTM DEVELOPMENT IS EXPECTED BY AFTERNOON FROM VICINITY OF COLD

FRONT AND DRYLINE/PACIFIC FRONT TRIPLE POINT OVER WRN OR CNTRL OK

SWD INTO THE EDWARDS PLATEAU REGION. THE COMBINATION OF STRONG

VERTICAL SHEAR AND MODERATE INSTABILITY INDICATE THE POTENTIAL FOR

SUPERCELLS AND/OR BOWING LINE SEGMENTS CAPABLE OF TORNADOES...

DAMAGING WINDS AND LARGE HAIL.

STORMS SHOULD GROW UPSCALE INTO A LINEAR CONVECTIVE SYSTEM MONDAY

NIGHT INTO TUESDAY MORNING WITHIN A STRONGLY SHEARED KINEMATIC

ENVIRONMENT. SUPERCELLS WILL REMAIN POSSIBLE WITHIN QLCS WITH A

CONTINUED THREAT OF TORNADOES...DAMAGING WINDS AND HAIL.

[NL]

Confirmed EF2 Tornado touched down in Atlanta City Georgia, state of emergency

declared extensive damage. live coverage here http://media.myfoxatlanta.com/live/#content_buffer

[Cookie]

There were 1 Tornado Reports Yesterday*| Today | Storms | Hail | Wind

Time (Z) Strength Location County State Lat Lon Comments

0140 UNK 1 NW ATLANTA FULTON GA 33.77 -84.43 BELOW

http://www.weathermatrix.net/stormmatrix/tornado/yesterday/

[Cookie]

Footage from that basketball game in the Atlanta Dome, luckily it was

a weak tornado as many people would have been injured or killed.

http://www.youtube.com/watch?v=7TT013NsSYc

thanks for the link mate <_<

[NL]

Tornado warnings now in effect, looks like a busy afternoon /evening as

conditions become more and more favourable for dangerous storms.

[Gorky]

You'd have to imagine there is a high chance of a tornado with this system atm...

Top Left - Base reflectivity

Top Right - Storm reletive velocity

Bottom Left - VIL

Bottom Right - Base Velocity

Ugh.. read on another forum that there are already reports of multiple fatalities with this storm and possible longtrack tornado as it crossed over Polk and Bartow counties.

[Cookie]

5 tornados since I was last online!!

There have been 5 Tornado Reports Today* | Yesterday | Storms | Hail | Wind

Time (Z) Strength Location County State Lat Lon Comments

1738 UNK 3 N CUMMING FORSYTH GA 34.25 -84.14 BELOW

A TORNADO WAS REPORTED CROSSING GA 400 NORTH OF CUMMING. (FFC)

1648 UNK 3 SW CARTERSVILLE BARTOW GA 34.14 -84.84 BELOW

POSSIBLE TORNADO HAS DAMAGED TREES AND BULDINGS NEAR WOODLAND HIGH SCHOOL. (FFC)

1642 UNK 3 E EUHARLEE BARTOW GA 34.14 -84.88 BELOW

POSSIBLE TORNADO KNOCKED DOWN SEVERAL TREES ALONG EUHARLEE ROAD. (FFC)

1635 UNK 1 N TAYLORSVILLE BARTOW GA 34.11 -84.99 BELOW

POSSIBLE TORNADO DAMAGE WITH SEVERAL TREES DOWN AND ROOF DAMAGE ALONG POPUM ROAD NORTH OF TAYLORSVILLE. (FFC)

1624 UNK 2 NW ARAGON POLK GA 34.07 -85.08 BELOW

POSSIBLE TORNADO ALONG HIGHWAY 101...EMERGENCY CREWS HAVE BEEN DISPATCHED DUE TO REPORTS OF HEAVY DAMAGE. (FFC)

http://www.weathermatrix.net/stormmatrix/tornado/

[NL]

Storms firing up along the warm front now with a squall line becoming

evident, am i right to assume this is where the triple point will originate..?

[justinflavin]

listening to WDUN Georgia over the internet.

baseball sized hail reported. they're live tracking the storm right now. i'll post a link in just a sec.

update: http://www.wdun.com/

click on the "listen live"

if you have a freecom musicpal internet radio , you'll find it under the "News Talk" section in Georgia, United States

[Cookie]

another 2 tornadoes taking it up to 7

There have been 7 Tornado Reports Today* | Yesterday | Storms | Hail | Wind

Time (Z) Strength Location County State Lat Lon Comments

1825 UNK 6 SSE HOMER BANKS GA 34.25 -83.46 BELOW

TORNADO WAS REPORTED NEAR INTERSTATE 85 NEAR EXIT 149. (FFC)

1758 UNK 3 S GAINESVILLE HALL GA 34.25 -83.83 BELOW

FIRE DEPARTMENT REPORTED TORNADO TOUCHED DOWN ON THE SOUTH SIDE OF GAINESVILLE. DAMAGE REPORTS ARE STILL COMING IN. (FFC)

[justinflavin]

WDUN radio has reported one fatality.

in case you dont know - google maps has a weather channel layer with radar

http://maps.google.com

just click on "my maps" and select the weather channel on the left.

local tv station in georgia - channel 2

http://www.wsbtv.com/index.html

state of emergency declared in atlanta city.

listening to callers on WDUN - a 2nd person has reported a "green sky". is this an effect of tornadic thunderstorms?

[Gorky]

High risk issued now.

Tornado confirmed by Law Enforcement west of Atlanta and will be moving into the city shortly.

www.11alive.com has streaming video.