View Full Version : Severe Weather - Apr 25 (Sat)



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venture
04-25-2009, 09:14 AM
Just doing the weekend in this post. Monday will have another risk, but will leave it to then...as well as the rest of next week.

Initial Discussion

A strong cold front will be dipping into NW Oklahoma throughout the day, as well as a dryline from NW OK through the NW Texas Panhandle into NM. Deep moisture has returned from the Gulf with dewpoints well into the mid 60s in a lot of locations. Some heating is also taking place out west this morning with partly cloudy skies. Current short term model guidance points to development during the mid to late afternoon today in NW Oklahoma. Most of the activity looks like it will be from I-40 North until it potentially consolidates until a compacted area of thunderstorms that will move east later tonight across Central Oklahoma. For SW Oklahoma, there will be less forcing in this area for most of the day due to the dryline being pretty far west. It looks like it may make a run for the state line this evening which should spark a few storms along it. Either way, the majority of the area today will be very unstable with CAPE values from 2000-4000 j/kg and LI numbers in the -4 to -9 range. Helicity values also appears to be reasonably high across western OK today, which will lead to a isolated tornado threat.

Primary Threats
Tornado: Moderate - 15% chance with in 25 miles of any given point in Western OK.
Hail: Very High - 45% chance with in 25 miles of any given point in Western OK of hail greater than 1", with a 10% or higher prop that hail will get over 2".
Wind: Moderate - 15% chance with in 25 miles of any given point in the Western half of OK of winds over 57 mph.

Will post more through out the day and add a discussion for tomorrow as well.

Day 1 Severe Weather Outlook: Storm Prediction Center Apr 25, 2009 1300 UTC Day 1 Convective Outlook (http://www.spc.noaa.gov/products/outlook/day1otlk.html)

Day 2 Severe Weather Outlook: Storm Prediction Center Apr 25, 2009 0600 UTC Day 2 Convective Outlook (http://www.spc.noaa.gov/products/outlook/day2otlk.html)

Real Time Weather Information

Satellite Image (1KM)
http://weather.cod.edu/data/satellite/1km/Oklahoma.gif

NEXRAD Mosaic Radar
http://weather.cod.edu/data/nexrad/Oklahoma.gif

Oklahoma Mesonet Current Conditions (red air temp, green dewpoint)
http://www.mesonet.org//data/public/mesonet/maps/realtime/current.wx.gif

Thunder
04-25-2009, 09:53 AM
I love reading Venture's posts on weather.

I just hate it when clouds want to stick around before all the action.

Charlie40
04-25-2009, 10:02 AM
Latest data is now pointing to the front pushing further into oklahoma than earlier expected. The triple point should now be focused just west of OKC so the higher severe threat will most likely be farther south than earlier predicted and include the okc metro and surrounding areas.

PennyQuilts
04-25-2009, 10:05 AM
I also love these reports.

Thunder
04-25-2009, 10:06 AM
Wow! Now, we look at the threat being pushed further south than earlier predicted, then all of the metro area should definately be on alert, because the storms can still hold together as they travel E/NE.

Jon27
04-25-2009, 10:30 AM
You know what's funny. I was talking to my wife last night about what the weather will do this weekend. I said to her "I bet venture will have a forecast up in the morning that I can check." I think venture should be the official OKCTalk weatherman.

Thanks for what you do venture.

westsidesooner
04-25-2009, 10:55 AM
You know what's funny. I was talking to my wife last night about what the weather will do this weekend. I said to her "I bet venture will have a forecast up in the morning that I can check." I tenture should be the official OKCTalk weatherman.

Thanks for what you do venture.

I'll second the nomination for Venture. And Charlie is right the cold front is moving further south than expected so far. Its now from about AMA to Woodward and still moving south. It should stall soon however. The clearing line is moving into western Oklahoma ATTM so it should start to warm up quickly. It cold be a very dangerous day for parts of the state. The storms should start mid to late afternoon and quickly become tornadic. Strong Tornadoes are very possible especially after dark this evening, so everyone keep your heads up. And stay safe.

For anyone interested there will be a storm chasing frenzy in western Oklahoma today. These sites have been posted here before but here they are again in case anyone missed them.

http://www.tornadovideos.net/full-screen-chaser-video.php

TwisterChasersLive (http://www.twisterchasers.com/twisterchaserslive.htm)

Live Storm Chase Video Network | SevereStudios.com (http://www.severestudios.com/livechase)

Charlie40
04-25-2009, 12:24 PM
Moderate Risk already posted for Sunday This includes central Oklahoma also. This could be upgraded to possibly a High Risk tomorrow if things come together right we could be looking at a tornado outbreak for tomorrow and also large hail is a pretty good bet as well baseball or larger. Stay weather aware today and tomorrow for sure.

venture
04-25-2009, 12:39 PM
http://www.spc.noaa.gov/products/md/mcd0562.gif

MESOSCALE DISCUSSION 0562
NWS STORM PREDICTION CENTER NORMAN OK
0127 PM CDT SAT APR 25 2009

AREAS AFFECTED...SOUTHEAST TX PANHANDLE...WESTERN OK...SOUTH CENTRAL
KS

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 251827Z - 252100Z

CORRECTED FOR INTERSTATE NUMBER

A TORNADO WATCH WILL BE REQUIRED BEFORE 22Z.

IN WAKE OF A LEAD DISTURBANCE MOVING ACROSS THE CENTRAL
PLAINS...SATELLITE SUGGESTS WEAK RIDGING RAPIDLY TRANSLATING OUT OF
NM. BACK EDGE OF THE LARGE SCALE RIDGING IS EXTRAPOLATED TO CLEAR
THE SOUTHERN HIGH PLAINS 21-22Z WITH INCREASING LARGE SCALE ASCENT
THEREAFTER.

COLD FRONT HAS ESSENTIALLY STALLED FROM NORTHWEST OF
WICHITA-WOODWARD-AMARILLO WITH THE DRYLINE BEGINNING TO MIX EAST
ALONG THE I-27 CORRIDOR. CLEARING NORTH OF THE FRONT MAY SIGNAL
THAT THE BOUNDARY WILL MOVE SLIGHTLY NORTHWEST THROUGH LATE
AFTERNOON AS THE DRYLINE MIXES INTO THE SOUTHEAST TX PANHANDLE.

THUNDERSTORM INITIATION SHOULD TAKE PLACE AROUND 22Z ALONG THE
DRYLINE/FRONT OVER THE SOUTHEAST TX PANHANDLE INTO SOUTH-CENTRAL
KS...THEN BUILD SOUTHWARD ALONG THE DRYLINE TOWARD CHILDRESS 22-00Z.
MLCAPES WILL RANGE 2000-2500 J/KG.

SOMEWHAT ANEMIC VERTICAL SHEAR PROFILES NOTED CURRENTLY SHOULD
IMPROVE BY INITIATION TIME AS STRONGER SOUTHWESTERLY MID-LEVEL WINDS
OVER THE SOUTHERN ROCKIES EDGE SOUTHEASTWARD. WIND PROFILES WILL
BECOME VERY CONDUCIVE FOR SUPERCELLS WITH GIANT HAIL GREATER THAN 2
INCHES IN DIAMETER. IN FACT...AS THE GREAT BASIN UPPER TROUGH
CONTINUES TOWARD THE SOUTHERN ROCKIES...SOUTHERLY BOUNDARY LAYER
FLOW IS EXPECTED TO INCREASE TO OVER 55 KTS DURING THE EVENING.
THIS WILL NOT ONLY MAINTAIN DISCRETE SUPERCELL STRUCTURES AS RICH
MOISTURE INFLOW CONTINUES...BUT ALSO BOOST 0-1KM STORM RELATIVE
HELICITY TO AT OR ABOVE 400 M2/S2. THIS WILL LIKELY YIELD
LONG-LIVED SUPERCELLS WITH POSSIBLE STRONG TORNADOES WHICH MAY LAST
WELL BEYOND SUNSET ACROSS WEST-CENTRAL/ NORTH-CENTRAL OK INTO
SOUTH-CENTRAL KS.

..RACY.. 04/25/2009


ATTN...WFO...ICT...OUN...DDC...LUB...AMA...

venture
04-25-2009, 12:50 PM
Strongly worded MCD from the SPC. This is definitely going to be a serious situation out west. Short term models are showing development to occur anytime between now and 5PM. Moisture convergence is pretty strong right now in NW OK, but is showing signs of increase farther south. There is still some inhibition left in the atmosphere, but again this will fade as instabilities increase.

Eastward extent is questionable right now, but wouldn't be shocked to see OKC included in the risk area before too long.

Thunder
04-25-2009, 01:23 PM
Venture, can you tell us the estimate speed movement of the storms that do develop? I also wonder if the high south wind will play a factor in shoving these storms into a squall line again.

Thunder
04-25-2009, 01:25 PM
Quote from KOCO's Andy


We’ve focused so much on the tornadoes that I feel the need to re-emphasize hail. Any of these storms will have the potential to produce damaging hail. Clean the garage out so you can put the car in. Even in central Oklahoma, clean it out today in case you have to put it in there tomorrow.

Today will be the day if anyone have their garage cluttered. Start cleaning them out, put them inside or out back in the shed/barn. Make room for that xtra car to put in the garage.

Also, if a neighbor have a carport, discuss with them if it is okay to borrow the space for the car, if they are not using it (car in garage) or if they do not plan to be home during specific time.

Thunder
04-25-2009, 01:28 PM
Venture, the radar is showing spotty development in the metro, but light. Are these only echos of the moisture in the air or an actual early development stage?

Karried
04-25-2009, 01:49 PM
I don't see any watches or warnings..

What's happening Venture?!!!

venture
04-25-2009, 01:54 PM
Looks like from the morning profiler, we would have storm motion from 250 degrees or ENE at around 25 mph. If the storms don't root down, they'll move a lot faster than that and more NE.

Anything around us is from the high moisture content in the air. Don't worry. We are going to have two areas of development. 1) Along the front to the NW and 2) in SW OK along the TX line.

Karrie - can you edit the topic for this thread to just have today's date. I'm going to do a second one for tomorrow due to the serious nature of having a tornado outbreak impacting the metro tomorrow.

Thunder
04-25-2009, 02:01 PM
I don't see any watches or warnings..

What's happening Venture?!!!

I am wondering about that myself.

I've seen watches posted way early with a lot less chance to be severe. Now, look at today, they are taking forever to post watches. The chances is there, it's all real, they must be posting watches in advance before people start making plans and going out.

venture
04-25-2009, 02:07 PM
On set of activity is planned for around 5PM, they'll probably put the tornado watch up anytime from now until 4PM.

Karried
04-25-2009, 02:09 PM
Well, my youngest is going (without us) to see the Lion King with neighbors tonight... should I be worried?

I hate when we're not together when storms are approaching.

Charlie40
04-25-2009, 02:13 PM
Tornado Watch should be posted for western/NW Oklahoma by or before 5 pm, it is possible that this may be issued as a PDS Watch stay tuned.

venture
04-25-2009, 02:15 PM
Update on SPC's new outlook...

...LATEST THINKING FOR SRN KS/OK...
ALTHOUGH SOME QUESTION REMAINS CONCERNING THE EXACT TIMING OF INITIATION...THUNDERSTORMS MAY INITIATE IN THE 22 TO 23Z TIMEFRAME ACROSS THE ERN TX PANHANDLE WITH SUPERCELLS MOVING INTO FAR WRN OK ALONG A FRONTAL BOUNDARY LOCATED FROM NEAR ALVA OK SWWD TO THE SERN TX PANHANDLE. THIS IS SUPPORTED BY THE LATEST 12Z HIGH RES NMM MODEL WHICH THEN INITIATES STORMS WITH LARGE HAIL AND WIND DAMAGE POTENTIAL ACROSS SRN AND ERN KS. THE THINKING CONTINUES THAT SUPERCELLS WITH VERY LARGE HAIL ARE LIKELY WITH AN ISOLATED STRONG TORNADO POSSIBLE IN WRN OK ESPECIALLY AS THE LOW-LEVEL JET CRANKS UP JUST AFTER DARK.

...CHANGES TO THE OUTLOOK...
THE GREATEST CHANGE TO THE OUTLOOK IS TO EXTEND THE 5 PERCENT TORNADO PROBABILITY INTO NERN KS AND 10 PERCENT TORNADO PROBABILITY NEWD ACROSS THE SRN KS WHERE MODERATE INSTABILITY AND LOW-LEVEL SHEAR WILL BE FAVORABLE FOR A FEW TORNADOES WITH SUPERCELLS THAT INITIATE LATE THIS AFTERNOON OR EARLY THIS EVENING. OTHER MINOR CHANGES INCLUDE BETTER ALIGNING THE MODERATE AND SLIGHT RISK TO THE LATEST SFC ANALYSIS...SHORT-TERM THUNDER GUIDANCE AND INITIALIZED RUC FIELDS. THIS CUTS SOME OF NRN LOWER MI OUT OF THE SLIGHT...ADDED PART OF NRN KS INTO THE SLIGHT AND MOVED THE 5 PERCENT HAIL AND WIND PROBABILITIES WWD INTO AREAS SOUTH OF MIDLAND TX. ANOTHER CHANGE IS TO NARROW THE 5 PERCENT PROBABILITY ACROSS NE TX AND THE ARKLATEX TO FAVOR THE MOST LIKELY STORM INITIATION AND GREATEST COMBINATION OF INSTABILITY AND VERTICAL SHEAR. ALSO EXTENDED THE 5 PERCENT HAIL AND WIND PROBABILITIES NEWD ACROSS SRN MD WHERE THE COMBINATION OF SHEAR AND INSTABILITY APPEARS FAVORABLE FOR A MARGINAL SEVERE THREAT IF STORMS CAN INITIATE.

venture
04-25-2009, 02:19 PM
Well, my youngest is going (without us) to see the Lion King with neighbors tonight... should I be worried?

I hate when we're not together when storms are approaching.

If they have a cell phone on them, have them keep it handy. Guidance is suggesting these will move north of the Metro, but things can change. Considering the dynamics available today, we'll have a few discrete supercells that usually have a tendency to hang a right and move more east than the current flow of storms.

venture
04-25-2009, 02:35 PM
http://www.spc.noaa.gov/products/watch/ww0183_radar.gif

Tornado Watch until 11PM coming out now.

Edit 339PM:
WW 183 TORNADO KS OK TX 252040Z - 260400Z
AXIS..75 STATUTE MILES NORTH AND SOUTH OF LINE..
60NNW CDS/CHILDRESS TX/ - 40SE TOP/TOPEKA KS/ ..AVIATION COORDS.. 65NM N/S /47E AMA - 37NW BUM/ HAIL SURFACE AND ALOFT..3 INCHES. WIND GUSTS..70 KNOTS.

Edit 341PM:
TORNADO WATCH PROBABILITIES FOR WT 0183
NWS STORM PREDICTION CENTER NORMAN OK
0339 PM CDT SAT APR 25 2009

WT 0183
PROBABILITY TABLE:
PROB OF 2 OR MORE TORNADOES : 70%
PROB OF 1 OR MORE STRONG /F2-F5/ TORNADOES : 30%
PROB OF 10 OR MORE SEVERE WIND EVENTS : 50%
PROB OF 1 OR MORE WIND EVENTS >= 65 KNOTS : 40%
PROB OF 10 OR MORE SEVERE HAIL EVENTS : 90%
PROB OF 1 OR MORE HAIL EVENTS >= 2 INCHES : 70%
PROB OF 6 OR MORE COMBINED SEVERE HAIL/WIND EVENTS : >95%

&&
ATTRIBUTE TABLE:
MAX HAIL /INCHES/ : 3.0
MAX WIND GUSTS SURFACE /KNOTS/ : 70
MAX TOPS /X 100 FEET/ : 550
MEAN STORM MOTION VECTOR /DEGREES AND KNOTS/ : 24030
PARTICULARLY DANGEROUS SITUATION : NO

EDIT 341PM:
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 183
NWS STORM PREDICTION CENTER NORMAN OK
340 PM CDT SAT APR 25 2009

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

PARTS OF SOUTHERN AND EASTERN KANSAS
PARTS OF NORTHERN AND WESTERN OKLAHOMA
PARTS OF EASTERN TEXAS PAN HANDLE

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 340 PM UNTIL 1100 PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 60 MILES NORTH NORTHWEST OF CHILDRESS TEXAS TO 40 MILES SOUTHEAST OF TOPEKA KANSAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

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.

OTHER WATCH INFORMATION...CONTINUE...WW 182...

DISCUSSION...SEVERE THUNDERSTORMS EXPECTED TO DEVELOP RAPIDLY ALONG NEARLY STALLED FRONTAL ZONE FROM NEAR EMP SWWD TO S OF AMA. WITH MLCAPES ABOVE 2500 J/KG AND VEERING SHEAR PROFILES IN PLACE...SUPERCELLS SHOULD BE THE PRIMARY MODE INTO THE EVENING. VERY LARGE HAIL GIVEN THE STEEP LAPSE RATES AND INSTABILITY IS EXPECTED WITH TORNADOES BECOMING AN INCREASED THREAT WITH ANY SUPERCELL THRU THE EVENING AS LOW LEVEL JET INCREASES AND BACKS AHEAD OF STRONG TROUGH APPROACHING FROM THE SRN ROCKIES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION VECTOR 24030.

venture
04-25-2009, 02:39 PM
Couple areas I am watching right now. Strong tower cumulus (TCU) developing in Wa****a/Caddo counties right now. As I'm typing this a weak radar echo as appeared. Another batch of TCU is in Major and Alfalfa counties. Decent CU field is spread out through the rest of W and SW Oklahoma, but there is little right now back along the dryline. This would tend to signal moisture isn't as deep there so the dryline should continue to mix east pretty well.

venture
04-25-2009, 02:52 PM
http://www.spc.noaa.gov/products/md/mcd0565.gif

Mesoscale discussion 0565
nws storm prediction center norman ok
0349 pm cdt sat apr 25 2009

areas affected...eastern tx panhandle...western ok and south-central ks

concerning...severe potential...tornado watch likely

valid 252049z - 252245z

update to earlier discussion.

Radar/satellite indicate the stalled front has begun a very slow retreat nwd through the tx panhandle and northwest ok while the dryline was mixing ewd to armstrong to crosby counties in tx.
Towering cu was bubbling at the intersection of the two over southwest gray county tx...in the free warm sector over wcentral ok and northeast along the front.

Larger scale ascent will improve after 22z in wake of the earlier disturbance moving into eastern ks per water vapor imagery. This will act to deepen the dryline/frontal circulation and initiation still looks to be across the eastern tx panhandle...northeast along the front into west-central/northwest ok in an hour or two /aside from activity developing in cntrl/ern ks/. Modifying the 20z norman sounding for a 88/58 air parcel suggests very little cap and mlcapes of over 2000 j/kg. Corridor from jericho-turkey tx northeast across erick...elk city...clinton...watonga and enid north to just nw of the front will have the highest severe probabilities through early evening.

Luke
04-25-2009, 03:02 PM
Thanks so much for doing this for us. I feel like we get a behind the scenes look at the weather. Very interesting. Keep it up!

:)

venture
04-25-2009, 03:25 PM
Strongest cell right now is out in Texas. Core has increased in intensity on it up through the storm. I'll try to post these images a bit more often when we get into the meat of the stuff tonight.

http://www.anvilcrawlers.com/coppermine/albums/userpics/10001/normal_kama_20090425_2126.png
http://www.anvilcrawlers.com/coppermine/displayimage.php?album=random&cat=0&pos=-2

Storm is now severe, our first one of the day in this part of the country. Hail is already over 2 inches with the storm.

venture
04-25-2009, 03:43 PM
Two nearly severe storms now in Grant and Alfalfa Counties...

Grant County storm is moving into Kansas, but it showing hail over an inch right now. Won't do anymore coverage on that.

Alfalfa County storm is moving NE at about 35mph and is right between Helena and Goltry. Hail over 1.5" possible right now.

Hard to do a 3D image on this one, because it is close to the radar site at Vance AFB. This is the basic look though:

http://www.anvilcrawlers.com/coppermine/albums/userpics/10001/normal_kvnx_20090425_2137.png

Looking NW into the storm.

Both are now severe warned.

westsidesooner
04-25-2009, 03:43 PM
New cells are going up further down the dryline near Childress and nw of Altus. These should be the ones to watch for the Metro later. Looks like they are going up fast.

venture
04-25-2009, 03:53 PM
If there is any doubt that Oklahoma is a chaser rich environment, this should erase those doubts. Every little green car and camera is a separate chaser right now.

http://www.anvilcrawlers.com/coppermine/albums/userpics/10001/normal_kfdr-42509-2147.png
AnvilCrawlers.com Photo Gallery: Click image to close this window (http://www.anvilcrawlers.com/coppermine/displayimage.php?pid=4&fullsize=1)

Thunder
04-25-2009, 03:55 PM
This sucks I'll miss the activities today. Well, showertime then off to work.

Venture, when I get back in 4 hours, I'll read all your posts. :-)

venture
04-25-2009, 04:17 PM
Beckham County storm, which is now servere, is the best looking of them all. Confirmed hail over an inch in this storm now. Woodward County just went severe as well.

Beckham County storm:
http://www.anvilcrawlers.com/coppermine/albums/userpics/10001/normal_kfdr_20090425_2209.png

Thunder
04-25-2009, 04:22 PM
The one that was NW of Altus looks like it is weakening. I think it might merge with the cell coming out of Texas.

Okay, need to put my socks and shoes on, grab a drink and drive out. Have fun, Venture!

venture
04-25-2009, 04:26 PM
Right now they are going to stay pretty parallel to each other. The Beckham Co storm is the best right now in the state. Hail size has come down a bit, but the top of it is still well over 50,000ft. So far nothing is showing any organized low level rotation.

venture
04-25-2009, 04:32 PM
Radar trends in NE Beckham Co on that storm are indicating low level rotation is now developing just west of Elk City city limits.

venture
04-25-2009, 04:59 PM
General thoughts on on going activity.

Northern Oklahoma - Two areas of storms. One is the severe storm in Grant County. Hail is now around an inch in this storm, however it remains pretty elongated and not all that impressive on radar. KWTV has live video on it now and shows some scud and a decent wall cloud. It is attached to the front, so it has the potential. Next is in Woods/Major Cos with some good sized hail, but overall not much else.

Southwest Oklahoma - Strongest storm is north of Elk City now. There are about 3 billion chasers on this one. Live video from chasers out there so a relatively flat base, not major lowered areas. It is reorganizing right now, it had a cell NE of it that it developed into and seems to be going through a split right now. Structure is fluctuating, but at times it looks like it is trying. Low level rotation has really backed off.

TX/OK Border - Storm coming in from Hemphill Co TX into Roger Mills Co OK is still the strongest one with the best structure. Live video on the storm shows a steady lowered area, but not much in the way of rotation. At times rotation has picked up, but never sustained. This is riding the front, so that should help it start rotating again as it continues to move ENE.

venture
04-25-2009, 05:29 PM
Another update...616PM. Current overall thoughts, storms are struggling establishing any low level rotation. Most starts are in areas with have LCLs, which are likely contributing to this. As they move east more, this could change. Best LCLs are general along Highway 81 and east and parts of Northern Oklahoma into Woods County.

North of I-40 Activity...Grant County storm hail to 2 inches but little organized low level rotation. This is an area of better LCL values which is why we are seeing a lot of scud on images from KWTV. Woods/Major Co storm is showing some monster hail on radar but nothing reported from the chasers. Structure is a bit better with this one and there is some broad low level rotation. Live video showing no organized wall cloud right now. There is a bunch of scattered hail storms in Woodward, Dewey and Major Counties. Nothing to worry much from them.

Roger Mills storm is showing a hook echo on radar now, it is completely covered by chasers right now. No wall cloud on live video from this storm (i'm monitoring about 3 different chasers right now)...but a lot seem to be out of position. Internet access is poor in this area through wireless companies. This does have decent low level rotation and will likely be our first to produce.

South of I-40...Custer Co storm which was by Elk City is recovering. Hail size has come up again as well as intensities. Nothing on video to get concerned about, but it seems to be developing a hook echo. Another hail storm is south of Elk City over to west of Cordell. Then another in Greer County. A couple more developing behind them.

venture
04-25-2009, 05:31 PM
Roger Mills is now tornado warned.

venture
04-25-2009, 05:38 PM
Spotters have a rotating wall cloud on the Major/Alfalfa County storm near Cleo Springs. Do have live streaming video of this up right now and it is an ugly thing.

So far on the Roger Mills storm, nothing on camera, lot of scud but no organized funnel as KFOR is reporting.

venture
04-25-2009, 06:00 PM
Tornado Warning Grant and Kay counties.

venture
04-25-2009, 06:10 PM
Very small funnel cloud, from what it appears, on video on the storm just SE of Clinton.

venture
04-25-2009, 06:22 PM
Mesoscale discussion 0569
nws storm prediction center norman ok
0638 pm cdt sat apr 25 2009

areas affected...portions ern tx panhandle...wrn/nrn ok...s-central through nern ks.

Concerning...tornado watch 183...

Valid 252338z - 260145z

the severe weather threat for tornado watch 183 continues.

Tornado threat will ramp up considerably during in next 2-3 hours...especially from wrn ok toward s-central ks. Continue ww.
Additional counties may be tacked onto srn fringes of ww over portions swrn/central ok. Given potential for frontal zone described below to lift nwd and expand warm sector over more of nern panhandle...nwrn ok and srn ks...svr potential may increase over nrn portions ww after 00z as well. Very large/damaging hail threat will continue with supercells from extreme ern tx panhandle newd across ern ks. Hail to 2.75 inch diameter has been reported with storm in custer county ok at 2315z...and even larger hail is possible over this region as supercell organization increases.

Sfc mesoanalysis shows quasistationary frontal zone from nrn fringes kc metro area swwd near emp...butler county ks...major and srn ellis counties ok. Reflectivity and vis animations each indicate front already has begun retreating nwd across central/ern tx panhandle...and should continue drifting nwd across hemphill/gray counties. Dryline -- initially intersecting cold front invof nwrn wheeler county tx...extends swd across hall county. This boundary may drift/retreat slightly wwd through 02z as boundary layer heating/mixing wanes on both sides of dryline.
With weakened vertical mixing...moist advection should contribute to increasing sfc dew points e of dryline...helping to maintain sfc-based inflow parcels and favorable buoyancy through early evening...mlcapes remaining around 2000 j/kg over wrn ok. Meanwhile llj will strengthen to over 50 kt through 02z...greatly increasing hodograph size. Expect 0-1 km srh to increase to 300-500 j/kg range over wrn ok during next 2-3 hours. Increasing deep-layer shear is expected over this region through evening as well...given strengthening mid-upper level winds evident in jtn/tcc profilers.

..edwards.. 04/25/2009

venture
04-25-2009, 06:28 PM
Storm on Bechkam/Wa****a County line has developed a hook echo with decent rotation. No live video in the area right now. Hail over 3 inches indicated with this storm.

Additionally storm in Clinton has slight rotation on the south side of it.

General overall trend seems to be an increase in rotation, so we could see a decent increase in tornadic potential (as expected by SPC in the discussion above) here before much longer.

If they would expand the watch, I would see Caddo, Canadian, Logan counties added on the south sides of it. We'll just have to watch and see what happens. No additional development seems to be happening farther SW.

venture
04-25-2009, 07:04 PM
Current Radar trends have northern OK activity to be on the down trend and just focus on rain/hail with some gusty winds. SW OK we still have 4 severe cells that have been bouncing back and forth trying to show signs of rotation or better organization. LCLs in this have have continued to rise and CIN has increased as well. So what that means is new storm development will be limited to he area immediately around existing storms and the tornado potential will be kept in check. Now shear is rapidly increase in NW OK down to about I-40 so this could either offset the other issues working against these storms, or be too late to have any real impact.

Now as long as this activity doesn't grow in coverage, persist through most of the night, and work over the atmosphere a lot...tomorrow is going to be a very active day.

venture
04-25-2009, 07:20 PM
Kiowa, Canadian and Caddo have been added to the watch.

Current thinking tornado threat will increase as shear increases with the threat ending around 1AM.

Jon27
04-25-2009, 07:33 PM
Thanks for the updates venture!! We've been out working in the yard all day, and guess we missed all the action. So what's this about a tornado outbreak in the metro tomorrow? Maybe I misunderstood.

venture
04-25-2009, 07:36 PM
I'll touch on the tornado threat for tomorrow in the other thread after all the evening models are done. The big thing, it is hard to get into detail since tonight's activity can have a major impact on tomorrow.

Jon27
04-25-2009, 07:41 PM
I don't know if any of you are on Twitter. I'm following someone by the screen name "okcweathermen". They just put a tweet up that said:

"Mike Morgan just compared the current storm to May 3rd 1999."

Why would he do that this early? Venture, is there any validity to this?

venture
04-25-2009, 07:59 PM
Tornado Warning for Kay county.

Chris - if Morgan is doing that, he should be slapped.

Karried
04-25-2009, 08:17 PM
That guy okcweathermen is trying to be funny. Ignore him.

He is just making fun of weatherman and Mike Morgan. He has targeted Mike and thinks it's humorous - it's not and I deleted him.

He's just a grown up bully, insulting, calling names and treating people like crap just because he can do it anonymously.

venture
04-25-2009, 08:25 PM
Sounds like someone who has little skill in their job or has a grudge. Too bad, since it seems he has an audience that follows him. Ah well.

Anywho. Models seem to have a good handle on how things are evolving tonight. No redevelopment has occurred father south and models don't call for any. All precip is expects to move NE through the night and be up into KS by 1AMish.

venture
04-25-2009, 08:43 PM
Tornado warning
national weather service norman ok
942 pm cdt sat apr 25 2009

the national weather service in norman has issued a

* tornado warning for...
Northwestern garfield county in northern oklahoma...

* until 1015 pm cdt

* at 942 pm cdt...national weather service doppler radar indicated a
severe thunderstorm capable of producing a tornado 4 miles west
of vance air force base...moving northeast at 15 mph.

* locations in the warning include breckenridge...enid...hunter...
Kremlin...north enid and vance air force base.

venture
04-25-2009, 09:04 PM
http://www.spc.noaa.gov/products/md/mcd0572.gif

Mesoscale discussion 0572
nws storm prediction center norman ok
0958 pm cdt sat apr 25 2009

areas affected...portions wrn/nrn ok...central/ern ks.

Concerning...tornado watch 183...

Valid 260258z - 260430z

the severe weather threat for tornado watch 183 continues.

Several supercells still evident within ww area...with mixed trends in both storm intensity and environmental parameters. Potentially tornadic supercell noted invof enid...strengthening storm is entering srn major county. Meanwhile steady to decreasing supercells are evident near and s of i-40 over wrn ok and within messy storm modes over s-central/sern ks.

Over ww area in general...tornado potential may have peaked...but cannot be considered finished yet. Diabatic sfc cooling is leading to increased mlcinh -- estimated at 50-100 j/kg attm over most of ww area based on modified raobs and ruc soundings. However...effective lifted parcels remain rooted at or very near sfc...and strengthening llj continues to enlarge low level hodographs...keeping 0-1 km srh 250-450 j/kg for any intense/rotating updrafts that can tap favorably moist air mass within that layer. Ww is scheduled to expire at 04z...but portions of this region may require additional ww issuance before then.

Farther n...across central/nrn ks...those portions of 40-50 kt llj that are moving around ok/srn ks convection will supply favorable moisture...within stg/elevated waa regime. Elevated mucape 1000-1500 j/kg with 30-40 kt effective shear will be favorable for large hail with most intense tstms.

venture
04-25-2009, 09:11 PM
Three areas of interest right now. The one tornado warned rotation by Enid. Another is just east of Longdale, and a third is SW of Watonga.

venture
04-25-2009, 09:19 PM
3D Radar Imagery of the current tornado that is now confirmed in Enid. What you are seeing are is the rotation in the storm actually mixing down, not the funnel itself. Just to clarify. : )

http://www.anvilcrawlers.com/coppermine/albums/userpics/10001/kvnx_20090426_0311.png

http://www.anvilcrawlers.com/coppermine/albums/userpics/10001/kvnx_20090426_0311~0.png

jstanthrnme
04-25-2009, 09:21 PM
Wow! very cool image!

venture
04-25-2009, 09:35 PM
Enid storm has some of the rotation extending down still, but definitely not mixing down as much as it did earlier.

Fairview storm has some rotation in it as well, not as tight or well defined as the one by Enid.

venture
04-25-2009, 09:43 PM
http://www.spc.noaa.gov/products/watch/ww0186_radar.gif

DISCUSSION...ENVIRONMENT WILL BE CHARACTERIZED BY LARGE LOW LEVEL
HODOGRAPHS/SRH AND PRESENCE OF ROTATING UPDRAFTS ABOVE FAVORABLE
BOUNDARY LAYER THETAE. TORNADO POTENTIAL EXPECTED TO CONTINUE FOR A
FEW MORE HOURS UNTIL AIR MASS STABILIZES TOO MUCH FOR SFC-BASED
EFFECTIVE INFLOW PARCELS...INVOF SFC BAROCLINIC ZONE.

Thunder
04-25-2009, 09:43 PM
Kool graphics, Venture.

I did came home, sat down, waited for the weather edition then suddenly a Tornado Warning near Enid. Mike Bennet and the Emergency Managers confirmed the tornado on the ground and there was extensive home damages.

Other news in the spotlight, I kept checking News 9, but it seem that Gary England was sleeping at the desk.

venture
04-25-2009, 09:47 PM
Quick update...Kremlin area has a confirmed tornado on the ground still, this is the Enid storm. Damage is reported with the storm in Enid.

New intensifying circulation by Orion to the Southwest of Fairview moving NE.

Another not as organized area of rotation is north of Isabella to the SW of Ringwood. This is all west of Enid.

Storms are moving into the area of better helicity / shear, so this is why we are likely seeing tornado production finally taking place.

jstanthrnme
04-25-2009, 10:10 PM
I really like these threads Venture, thanks again for all of the great information. Like Luke said, its kind of a behind the scenes look at meteorology. Your information is as good/better than the heads on tv.

Though I almost feel the need to have a glossary handy to figure out some of the terms and abbreviations, its more objective than what Gary, Rick, or Mike have to say, and that is the reason I like to keep up with these threads.

I'll definately be checking in tommorow.