Severe Weather - April 16, 17, & 18 (Thur, Fri, Sat)

[Luke]

Looks like a week until the next system rolls in.

As for today, hail risk has been increased with a hatched area by SPC over most of Central and Western Oklahoma. Short range models seem to be in decent agreement today develop isolated/scattered activity mostly after 1PM in the west. Timing seems a bit slower than last night, with activity in Central OK after 8PM til about midnight.

NSSL Realtime WRF model Forecasts

http://www.emc.ncep.noaa.gov/mmb/mpy..._1000m_f24.gif

Tornado threat today is pretty nil, except (as stated yesterday) up along the KS border by the low.

Because I am interested in the scientific aspects of weather development, what am I to get from those to links above?

[venture]

Those are two forecast models that provide a simulated radar image for activity during a time period. They are both for 7PM tonight...well actually the first link gives you the whole package than you can pick your time (7PM being 24hr).

Updating current activity. Some storms have fired in SW KS under the low. One observed tornado already with the main cell. Instability continues to increase across western OK with clear skies. Reference: http://w1.spc.woc.noaa.gov/exper/mes...s.php?sector=3

Update again...1:19PM: Both cells in SW Kansas are now tornado warned. We will likely need to watch the track of this low very carefully as it seems we'll get a classic cold core tornado event with it.

[venture]

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 167
NWS STORM PREDICTION CENTER NORMAN OK
130 PM CDT SAT APR 18 2009

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

CENTRAL KANSAS
NORTHWEST OKLAHOMA

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 130 PM UNTIL
700 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 55 STATUTE
MILES EAST AND WEST OF A LINE FROM 70 MILES NORTH OF DODGE CITY
KANSAS TO 70 MILES SOUTH OF ALVA OKLAHOMA. FOR A COMPLETE
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE
(WOUS64 KWNS WOU7).

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 165...WW 166...

DISCUSSION...THUNDERSTORMS HAVE BEGUN TO DEVELOP BENEATH COLD UPPER
LOW OVER SOUTHWEST KS. DEVELOPMENT IS EXPECTED TO OCCUR SOUTHWARD
ALONG DRYLINE INTO NORTHWEST OK DURING THE NEXT FEW HOURS AS WELL.
BACKED LOW LEVEL WINDS...STEEP LAPSE RATES...AND AMBIENT VORTICITY
WILL PROMOTE A RISK OF TORNADOES IN THIS REGION.
OTHERWISE...SPLITTING SUPERCELLS CAPABLE OF VERY LARGE HAIL WILL BE
THE MAIN THREAT.

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
400. MEAN STORM MOTION VECTOR 24025.

[venture]

Rapid Development under way throughout most of the watch box area.

[Thunder]

How soon do you think more developments will occur further south of those?

I'm seeing some clearing now and feeling the heat.

The main low core, is it still moving SE or did it start to shift toward NE?

[venture]

Development is already down to Sweetwater now (west of Elk City). I would expect any Metro impacting to be more after 5PM. The main low is forecast to skirt along the OK/KS border, so there MIGHT be a risk of an isolated tornado in the Metro (Kingfisher County is in the watch and they are in the Metro)...but I would say we will see more hail storms develop this far south.

Instability gets really limited right now in NC Oklahoma and that is spilling into OK County. However the sun should go to work on that.

Refer to: sbcp

On that page, no the 1000 j/kg line for SBCAPE. You can also see the most unstable area is in NW OK where current development is taking place.

[venture]

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 168
NWS STORM PREDICTION CENTER NORMAN OK
310 PM CDT SAT APR 18 2009

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

CENTRAL OKLAHOMA
NORTH CENTRAL TEXAS

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 310 PM UNTIL
1000 PM CDT.

HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES EAST
NORTHEAST OF ALVA OKLAHOMA TO 60 MILES SOUTHEAST OF WICHITA FALLS
TEXAS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

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 165...WW 166...WW 167...

DISCUSSION...SCATTERED STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO
DEVELOP IN THE NEXT FEW HOURS OVER PARTS OF CENTRAL OK...AHEAD OF
APPROACHING MID LEVEL SHORTWAVE TROUGH OVER THE TX PANHANDLE. STEEP
LAPSE RATES AND STRONG EFFECTIVE SHEAR WILL PROMOTE SUPERCELL
STRUCTURES CAPABLE OF VERY LARGE HAIL. STORMS MAY BECOME MORE
LINEAR IN NATURE LATER THIS EVENING AS PRIMARY FORCING OVERSPREADS
REGION.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 400. MEAN STORM
MOTION VECTOR 24035.

[venture]

The national weather service in norman has issued a

* tornado warning for...
Central woods county in northwest oklahoma...

* until 400 pm cdt

* at 321 pm cdt...national weather service doppler radar indicated a
severe thunderstorm capable of producing a tornado 6 miles
southeast of freedom...moving north at 10 mph.

[Thunder]

I walked by the tv and it was on a spanish channel. There was a map that had most of the state in green. My jaws dropped then switched to 4 to only see it blue. LOL

[bretthexum]

Anyone see the snowfall in Denver?
This whole global warming thing still working out for you?

Oh brother. Let's keep the politics out of the weather thread, OK?

[Thunder]

Squall line out west moving closer. It looks like several storms is trying to fire up in front of the squall line. I think these storms could be capable of being a major hail producer supercell and probably an elevated threat for a tornado or two.

A storm south of Norman is trying to gain strength.

[venture]

Oh brother. Let's keep the politics out of the weather thread, OK?

Just simply click the and mods will get the posts deleted. They have been doing a great job helping us to keep these threads clean. : )

[venture]

Run down on current radar trends. Line of storms now extends from the OK/KS border in Grant County down Highway 81 through Enid, Kingfisher, approaching El Reno, to Chickasha. Additional storms are developing back towards Lawton. Everything right now is below severe levels, with the strongest near Hennessey with some marginal hail.

Dewpoints south of I-40 are struggling to stay near 50 degrees right now, so the very dry air will limit any strengthening or expansion of convection. Though some storms may get a bump as the storm system begins to pull out, I think we've seen the most severe portion of this episode.

[Jon27]

Oh brother. Let's keep the politics out of the weather thread, OK?

[venture]

Up tick in storms with the main system pulling out is under way. Everything should be out of here before much long though. One hail report in Edmond of marginal severe hail, around 0.75" - starting this year the Central Region of the NWS (Oklahoma is in the Southern Region) is testing the impact of no longer considering anything less than a full 1 inch in diameter severe. Essentially the storm in OK County right now warned, would only be so if there was an actual case for winds over 58 mph.

[Thunder]

Well, that was fun. Wait, that was awesome! I got completely soaked and my 3 years old shoes, which have sum frontal torn got my feet and socks completely wet! I think I felt tiny hails. When it passed, I could see the back end, so frickin awesome! I saw bumpy clouds, forgot the name of them, the ones that hangs down. Beautiful storm!

[venture]

Mammatus. : )

Those usually make for some very nice photography.

[OKCisOK4me]

Mammatus. : )

Those usually make for some very nice photography.

Booby clouds, lol. Can I say that on here?

[kevinpate]

sure you can say it, you can even take photos, just don't sext them to others.