Oklahoma Severe Weather Discussion - April 2011

[venture]

Potential Severe Weather Outbreak looks possible for Thursday for parts of the state from I-35 to east.





DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT WED APR 13 2011

VALID 141200Z - 151200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF SE KS...ERN OK...FAR SW MO AND FAR NW AR...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE CNTRL PLAINS...SRN PLAINS...MID-MO VALLEY...OZARKS AND ARKLATEX...

...REGIONAL OUTBREAK OF SEVERE STORMS AND POSSIBLY TORNADOES ACROSS PARTS OF THE SRN AND CNTRL PLAINS THURSDAY AFTERNOON AND EVENING...

...SRN PLAINS/CNTRL PLAINS/OZARKS/MID-MO VALLEY...
AN IMPRESSIVE NEGATIVELY-TILTED UPPER-LEVEL TROUGH IS FORECAST TO CLOSE OFF OVER THE CNTRL HIGH PLAINS THURSDAY. THE EXIT REGION OF A 70 TO 80 KT MID-LEVEL JET ROUNDING THE BASE OF THE TROUGH WILL CREATE STRONG DEEP LAYER SHEAR PROFILES ACROSS THE REGION CREATING AN ENVIRONMENT FAVORABLE FOR SEVERE STORM DEVELOPMENT. AT THE SFC...A WELL-DEVELOPED LOW IS FORECAST TO DEEPEN QUICKLY ACROSS CNTRL KS AT MIDDAY MOVING NWD INTO NEB. THUNDERSTORM INITIATION SHOULD FIRST OCCUR NEAR AND TO THE NORTH OF THE SFC LOW DURING THE AFTERNOON WHERE STRONG LOW-LEVEL CONVERGENCE AND COLD TEMPS ALOFT SHOULD RESULT IN A LARGE HAIL THREAT. THE MODELS ARE CONSISTENT DEVELOPING STRONG CONVECTION DURING THE LATE AFTERNOON SEWD INTO CNTRL TO ERN KS AND ECNTRL OK ALONG THE WRN EDGE OF AN AXIS OF MODERATE INSTABILITY. THE STORMS SHOULD INITIATE JUST TO THE EAST OF A DRYLINE ORIENTED NORTH TO SOUTH ALONG THE I-35 CORRIDOR.

FORECAST SOUNDINGS ALONG THE INSTABILITY AXIS AT 00Z FRIDAY SHOW MLCAPE VALUES FROM 1500 J/KG IN ECNTRL KS TO 2500 TO 3000 J/KG IN ECNTRL OK. THIS COMBINED WITH 0-6 KM SHEAR VALUES OF 50 TO 65 KT WILL CREATE A THERMODYNAMIC AND SHEAR ENVIRONMENT FAVORABLE FOR SUPERCELLS AND LARGE HAIL ESPECIALLY ACROSS THE MODERATE RISK AREA IN SE KS...ERN OK...FAR NW AR AND FAR SW MO. THE GREATEST SEVERE THREAT COVERAGE SHOULD OCCUR ON THE NOSE OF A PLUME OF STEEP MID-LEVEL LAPSE RATES WHICH COMBINED WITH THE MODERATE INSTABILITY AND STRONG DEEP LAYER SHEAR WILL BE FAVORABLE FOR VERY LARGE HAIL WITH THE MORE DOMINANT SUPERCELLS. TORNADOES WILL ALSO BE POSSIBLE ESPECIALLY AS THE LOW-LEVEL JET STRENGTHENS DURING THE EARLY EVENING. FORECAST SOUNDINGS IN ERN OK FROM 00Z TO 03Z SHOW 0-3 KM STORM RELATIVELY HELICITIES OF 350 TO 450 M2/S2 WHICH WILL MAKE AN ISOLATED THREAT FOR STRONG TORNADOES POSSIBLE. HOWEVER...THIS THREAT SHOULD BE CONDITIONAL UPON MOISTURE RETURN AND STORM MODE. SQUALL-LINE DEVELOPMENT INSTEAD OF THE TENDENCY FOR DISCRETE CONVECTION WOULD RESULT IN MORE OF A WIND DAMAGE THREAT.

FURTHER SOUTH ACROSS NE TX...FORECAST SOUNDINGS AT 21Z TO 00Z SHOW A STOUT CAPPING INVERSION WHICH IS EXPECTED TO HOLD FOR MUCH OF THE AFTERNOON AND EVENING. FOR THIS REASON...THE SEVERE THREAT SHOULD DROP OFF QUICKLY WITH SWD EXTENT IN NE TX. DURING THE EVENING AND OVERNIGHT PERIOD...THE MODELS ARE CONSISTENT WITH DEVELOPING AN MCS IN THE OZARKS AND DRIVING THIS FEATURE EWD INTO THE LOWER TO MID MS VALLEY. ALTHOUGH SEVERE THREAT COVERAGE SHOULD DECREASE DURING THE LATE EVENING AND OVERNIGHT PERIOD...A THREAT FOR HAIL AND ISOLATED WIND DAMAGE MAY CONTINUE AS FAR EAST AS SCNTRL MO AND ECNTRL AR WHERE SFC DEWPOINTS SHOULD BE IN THE LOWER 60S F AND 40 TO 50 KTS OF LOW-LEVEL FLOW IS FORECAST.

..BROYLES.. 04/13/2011

[venture]

Taking a look at this evening's model runs for central Oklahoma, it all depends on where the dryline is when storms start. If the dryline slows down, severe threat will move west more...speeds up, further east. Right now initiation per the GFS model has storms starting almost right on I-35 from border to border. NAM doesn't initiate precip until well after 6PM about 30-50 miles east of I-35. GEM model moves the dryline almost to Tulsa-McAlester line by 5-7PM time frame, well faster than the other two. UK-MET is a bit slower and has precip chances back west of I-35 a bit.

So there is potential we could see some storms here in Central sections, but chances aren't very high right now.

Outlook Update...Next Storm chances...
- Monday 4/18: Mostly Northern and Eastern Oklahoma.
- Tuesday 4/19: Rain chance East.
- Thursday 4/21: Storm chance most of the state except NW.
- Friday 4/22: Significant rain possible Eastern 2/3rds of OK.
- Monday 4/25: Storms Eastern 2/3rds of OK.
- Thursday 4/28: Chance of rain Northern & Eastern OK.

[Thunder]

What do YOU think will happen with our precious dryline?

[venture]

What do YOU think will happen with our precious dryline?

Ask me Thursday afternoon. :-) I'm not going to touch dryline placement this far out since it all depends on how fast it mixes east.

[venture]

Extreme Fire Danger returns Thursday...

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE NORMAN OK
327 AM CDT WED APR 13 2011

...EXTREME WILDFIRE POTENTIAL POSSIBLE THURSDAY...

...A DRYLINE WILL MOVE EAST ACROSS PORTIONS OF OKLAHOMA AND
WESTERN NORTH TEXAS. STRONG WINDS... LOW HUMIDITIES... AND HOT
TEMPERATURES WILL COMBINE TO INCREASE THE WILDFIRE POTENTIAL WEST
OF THE DRYLINE. A COLD FRONT WILL MOVE ACROSS THE REGION THURSDAY
NIGHT SHIFTING WINDS TO THE NORTHWEST MAKING FIREFIGHTING EFFORTS
OF ANY ONGOING FIRES DIFFICULT.

OKZ009-010-014>018-021>024-027-033>039-044-045-TXZ083>090-131630-
/O.NEW.KOUN.FW.A.0020.110414T1500Z-110415T0200Z/
ELLIS-WOODWARD-ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-BECKHAM-
WA****A-CADDO-CANADIAN-GRADY-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-COTTON-JEFFERSON-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
327 AM CDT WED APR 13 2011

...FIRE WEATHER WATCH IN EFFECT FROM THURSDAY MORNING THROUGH
THURSDAY EVENING FOR PARTS OF WESTERN AND CENTRAL OKLAHOMA AND ALL
OF WESTERN NORTH TEXAS...

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A FIRE WEATHER
WATCH...WHICH IS IN EFFECT FROM THURSDAY MORNING THROUGH THURSDAY
EVENING.

* WIND...SOUTHWEST TO WEST WINDS AT 20 TO 30 MPH WITH HIGHER GUSTS.

* HUMIDITY...5 TO 20 PERCENT.

* TEMPERATURE...UPPER 70S TO AROUND 90.

* IMPACTS...ANY FIRES THAT DEVELOP WILL LIKELY SPREAD RAPIDLY.
OUTDOOR BURNING IS NOT RECOMMENDED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MONITOR WEATHER FORECASTS AND INFORMATION.

[Dustin]

Please tell me rain is in the near future.... please..

[Roadhawg]

When's the last time we had any rain?

[Achilleslastand]

I think the last time we had a significant amount of rain was last July.

[BG918]

I think the last time we had a significant amount of rain was last July.

Hence the reason nearly the entire state is in an extreme drought. At this point we need a really wet late spring and likely a couple tropical systems moving over the state from the Gulf to get caught up.

Remember we were in nearly the same dire situation in 2005-06 and 2007 was a record-breaking year for rainfall ending the drought. Unfortunately I think we are going to see more and more such dry and wet cycles in this part of the country.

[venture]

Updated Day 2 Outlook continues to indicate a potential severe weather outbreak tomorrow from I-35 and to the east.

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1226 PM CDT WED APR 13 2011

VALID 141200Z - 151200Z

...THERE IS A MDT RISK OF SVR TSTMS SERN KS/ERN OK AND EXTREME NWRN
AR/SWRN MO...

...THERE IS A SLGT RISK OF SVR TSTMS SRN-CNTRL PLAINS/OZARKS/LOWER
MO VALLEY...

...A SIGNIFICANT SEVERE WEATHER EPISODE IS POSSIBLE THURSDAY
AFTERNOON/EVENING ACROSS SERN KS/ERN OK AND EXTREME NWRN AR/SWRN
MO--THIS THREAT WILL INCLUDE VERY LARGE HAIL AND A FEW DAMAGING
TORNADOES...

...SRN-CNTRL PLAINS/OZARKS/MID MO VALLEY...
A VIGOROUS SHORTWAVE TROUGH OVER CO/NM AT THE START OF THE PERIOD
WILL QUICKLY TRANSLATE EWD AND CONTINUE TO AMPLIFY AND EVOLVE INTO A
NEGATIVELY TILTED TROUGH AND CLOSE OFF INVOF OK/KS BORDER BY
THURSDAY EVENING. STRONG DIFFLUENT UPPER TROPOSPHERIC FLOW WILL
OVERSPREAD PORTIONS OF THE CNTRL PLAINS/LOWER MO VALLEY SWD TO THE
ARKLATEX CREATING WIND PROFILES VERY FAVORABLE FOR ORGANIZED SEVERE
STORMS. IN THE LOW LEVELS...A CYCLONE WILL DEEPEN AS IT MOVES ENEWD
FROM THE SRN HIGH PLAINS TOWARDS KS/MO BORDER BY 12Z FRIDAY. RAPID
MASS ADJUSTMENT WILL BE ONGOING ACROSS THE AREA CONCURRENT WITH
BOUNDARY LAYER DESTABILIZATION IN ADVANCE OF STRONG HEIGHT FALLS
MOVING TOWARDS THE REGION. THIS WILL OCCUR AS AN INFLUX OF LOW
LEVEL MOISTURE RETURNS NWD INTO THE CNTRL-SRN PLAINS ALONG AND E OF
A N-S ORIENTED DRYLINE FORECAST TO BE NEAR THE I-35 CORRIDOR IN OK
AND S-CNTRL KS THURSDAY AFTERNOON. STEEP LAPSE RATES DUE IN PART TO
COLD MID LEVEL TEMPS ALOFT /-16 TO -20 DEG C AT H5/ WILL OVERSPREAD
NRN OK WHICH WILL LEAD TO A DESTABILIZING WARM SECTOR FROM ERN TX
NWD THROUGH OK/SERN KS...ARCING NWWD TO THE N OF THE SURFACE LOW
OVER CNTRL KS.

CURRENT INDICATIONS ARE LOWER 60S DEG F SURFACE DEWPOINTS WILL
ADVECT AS FAR N AS NERN OK. STRONG LOW LEVEL CONVERGENCE INVOF THE
DEEPENING SURFACE LOW OVER KS AND STEEPENING LOW LEVEL LAPSE RATES
SHOULD RESULT IN SURFACE-BASED TSTM DEVELOPMENT BY EARLY AFTERNOON
IN WAKE OF WARM ADVECTION STORMS IN THE MORNING HOURS ACROSS
CNTRL-ERN KS. SEVERE STORMS ARE EXPECTED TO DEVELOP FIRST NEAR THE
LOW AND THEN SWD ALONG THE DRYLINE BY MID-LATE AFTERNOON IN SERN KS
INTO ERN OK. A NARROW TONGUE OF MID 50S BOUNDARY LAYER DEWPOINTS AS
FAR N AS CNTRL KS AND STEEP LAPSE RATE PROFILES /YIELDING 500-1500
SBCAPE/ WILL LIKELY RESULT IN SUPERCELLS CAPABLE OF LARGE HAIL/DMGG
WINDS AND ISOLD TORNADOES IN BACKED LOW LEVEL FLOW N AND E OF THE
SURFACE LOW OVER KS. FORECAST SOUNDINGS FARTHER S ALONG THE DRYLINE
INDICATE A MORE VOLATILE THERMODYNAMIC ENVIRONMENT WITH MODERATE TO
STRONG INSTABILITY DEVELOPING BY MID-LATE AFTERNOON. STRONG HEATING
WILL RESULT IN MLCAPE VALUES CLIMBING INTO THE 1500-3000 J/KG RANGE
AS MID LEVEL LAPSE RATES /8 DEG C PER KM/ OVERSPREAD THE WARM
SECTOR. A N-S BAND OF SCATTERED INITIALLY DISCRETE SUPERCELLS
CAPABLE OF VERY LARGE HAIL WILL MOVE E OFF THE DRYLINE. LOW LEVEL
SHEAR IS FORECAST TO INCREASE TOWARDS EVENING AS LARGE CLOCKWISE
CURVED HODOGRAPHS /300-450 EFFECTIVE SRH/ WILL SUPPORT THE
POSSIBILITY OF STRONG TORNADO/S...IN ADDITION TO VERY LARGE
HAIL/DMGG WINDS...WITH THE MORE INTENSE SUPERCELLS. THIS ACTIVITY
IS FORECAST TO CONTINUE EWD DURING THE OVERNIGHT HOURS INTO THE
OZARKS AND ARKLATEX...MAINTAINING A SEVERE RISK AS THE UPPER PV
ANOMALY SURGES EWD INTO THE OZARKS. IT IS LIKELY THAT STORMS WILL
CONSOLIDATE BASED ON THE MAGNITUDE OF FORCING AND LEAD TO EVENTUAL
UPSCALE GROWTH INTO AN MCS. THIS MAY ACT TO TEMPER TORNADO
POTENTIAL SOME BUT CONTINUE THE SEVERE THREAT THAT MAY EXTEND AS FAR
E AS THE LOWER MS RIVER VALLEY BY DAYBREAK FRIDAY. FARTHER S INTO
NERN TX...STORM COVERAGE IS EXPECTED TO REMAIN MORE ISOLD AND BE
DELAYED UNTIL THE EVENING HOURS AS FORCED ASCENT ERODES REMAINING
CINH. ANY STORMS THAT DEVELOP WILL BE CAPABLE OF LARGE HAIL/DMGG
WINDS AND AN ISOLD TORNADO.

..SMITH.. 04/13/2011

[Bunty]

Interesting how Mike Morgan on KFOR thinks he has it pinned down good enough as to rate the risk for severe weather on Thursday as HIGH from Enid to Stillwater, but only rates it slight for much of OKC.

[Thunder]

Interesting how Mike Morgan on KFOR thinks he has it pinned down good enough as to rate the risk for severe weather on Thursday as HIGH from Enid to Stillwater, but only rates it slight for much of OKC.

Linda: Welcome to Oklahoma's News Channel 4 at 4:30. We begin the day with severe storms risk in the state with Mike Morgan.
Mike: AHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!!!!!!
Kevin: It's that bad, folks.

[jn1780]

Interesting how Mike Morgan on KFOR thinks he has it pinned down good enough as to rate the risk for severe weather on Thursday as HIGH from Enid to Stillwater, but only rates it slight for much of OKC.

They need need to come up with their own severe weather classification system so people don't confuss it with the official NWS severe weather outlooks. The weather channel has the "TOR:CON Index".

Maybe the NWS will upgrade that area to high risk. We just won't know until tomorrow.

[venture]

Oy. Anywho. Here we go...

So for OKC proper it comes down to dryline placement. NAM moves the dryline to essentially right on top of I-35 by 7PM. GFS has it further east by about 40 miles. Storms will fire along and ahead of the dryline and move to the east. There is also the possibility for the dryline to hang up somewhere over the metro. Forecast sounds show it passing OKC mid-afternoon, but start west (north) of Norman through early evening. We'll have have to wait and see, but where ever that dryline goes will play a huge part in weather Thursday.

Still plenty of variables in play tomorrow, so nothing is locked in. Don't be shocked to see the moderate risk brought back west very close to the metro area. However, the slight risk won't really go much further west than us as well. The potential is there for severe storms with very large hail and a few tornadoes. There are complications in the forecast now where an outbreak may not occur where it is expected. We very well could get a lot of rotating storms with larger hail north of I-40 and more tornadic activity south. We'll just have to wait and see though.

In addition to the severe weather threat, the Fire Weather Watch has been extended all the way east to I-35. Very dry air will be behind the dryline and fire danger will rise quickly as it passes. You could almost say tomorrow will be a story of fire and ice...just that the ice will be in the form of extremely painful "snowballs" raining down from the sky.

New outlook will be out soon, will post once it is published. I understand Morgan went with a "high" risk on his map for Thursday...I don't expect SPC to do a high risk until later in the day if things point to an extensive outbreak.

[venture]

New Day 1 Discussion is out...

MODERATE RISK is along and to the east of a line from 10 mi E of Newkirk to Pawnee to Chandler to 8 mi E of Shawnee to Ada to Durant. Significant Tornadoes, Hail over 2 inches, and severe winds are probable in the moderate risk area.

SLIGHT RISK is along and to the east of a line from 13 mi E of Cherokee to Enid to 7 mi E of Kingfisher to Mustang to Blanchard to Dibble to Lindsay to Fox to Wilson to 6 mi W of Thackerville. All of the Oklahoma City Metro area, except for far western sections, are included in the SLIGHT RISK area.

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT THU APR 14 2011

VALID 141200Z - 151200Z

...THERE IS A MDT RISK OF SVR TSTMS FROM SERN KS THROUGH ERN OK INTO WRN AR AND EXTREME NERN TX...

...THERE IS A SLGT RISK OF SVR TSTMS FROM A PORTION OF THE CNTRL AND SRN PLAINS INTO THE LOWER MS VALLEY REGION...

...SYNOPSIS...

SPLIT FLOW UPPER PATTERN WILL PREVAIL THURSDAY WITH A POTENT SHORTWAVE TROUGH CURRENTLY OVER THE GREAT BASIN EMERGING FROM SRN BRANCH AND CONTINUING THROUGH THE CNTRL AND SRN PLAINS. A SURFACE CYCLONE WILL DEEPEN AND LIFT NEWD THROUGH KS WITHIN UPPER JET EXIT REGION. STATIONARY FRONT NOW EXTENDS FROM NRN MO SWWD THROUGH KS INTO NWRN OK. ERN KS PORTION OF FRONT MAY LIFT NWD INTO EXTREME SERN NEB AS SURFACE LOW DEEPENS OVER CNTRL KS. DRYLINE WILL SHARPEN AND EXTEND SWD FROM THE LOW THROUGH CNTRL OK AND N-CNTRL TX. PACIFIC FRONT WILL ADVANCE EWD AND EVENTUALLY MERGE WITH DRYLINE ACROSS ERN OK...THEN CONTINUE TOWARD THE LOWER MS VALLEY OVERNIGHT.

...KS...ERN OK THROUGH THE LOWER MS VALLEY AREA...

RICH GULF MOISTURE RESIDES ACROSS SRN TX WITH LOW 60S DEWPOINTS AS FAR NORTH AS CNTRL TX. A SLY LOW LEVEL JET WILL PERSIST FROM CNTRL-NCNTRL TX AND SHIFT NWD THROUGH ERN OK AND KS IN RESPONSE TO DEEPENING SURFACE LOW. THIS WILL RESULT IN NWD ADVECTION OF RICHER MOISTURE WITH LOW 60S DEWPOINTS LIKELY ACROSS CNTRL-ERN OK AND NEAR 60 DEWPOINTS INTO SERN KS. EWD ADVECTING EML PLUME AND COLD TEMPERATURES ALOFT ACCOMPANYING THE UPPER TROUGH SHOULD YIELD 8-8.5 C/KM 700-500 MB LAPSE RATES ABOVE THE MOISTENING BOUNDARY LAYER. SOME STRATUS WILL LIKELY DEVELOP EARLY THURSDAY FROM PARTS OF N-CNTRL TX...OK AND KS IN ASSOCIATION WITH RETURN OF RICHER MOISTURE. HOWEVER...DIABATIC WARMING IS EXPECTED BY EARLY AFTERNOON AS LOW CLOUDS MIX OUT...RESULTING IN AXIS OF 2000-2500 J/KG MLCAPE FROM N-CNTRL TX...ERN HALF OF OK INTO SERN KS WITH MORE LIMITED INSTABILITY FARTHER NORTH.

ELEVATED STORMS WILL LIKELY BE ONGOING OR DEVELOP EARLY WITHIN ZONE OF ISENTROPIC LIFT NORTH OF THE FRONT FROM NRN KS INTO NEB. THIS ACTIVITY COULD POSE A THREAT FOR MARGINALLY SEVERE HAIL. INITIAL SURFACE BASED STORMS ARE EXPECTED BY EARLY AFTERNOON WITHIN ZONE OF DEEP ASCENT ASSOCIATED WITH UPPER JET EXIT REGION INTERACTING WITH OCCLUDED FRONT/DRYLINE ACROSS CNTRL KS. VERTICAL SHEAR WILL SUPPORT SUPERCELLS WITH LARGE HAIL AND TORNADOES POSSIBLE. OTHER STORMS WILL LIKELY INITIATE ALONG THE DRYLINE FROM SRN KS...CNTRL-ECNTRL OK...AND POSSIBLY INTO N-CNTRL TX BY MID-LATE AFTERNOON. THESE STORMS WILL LIKELY BE DISCRETE SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND TORNADOES. GREATEST TORNADO THREAT IS EXPECTED IN MODERATE RISK AREA WHERE 0-1 KM HODOGRAPH SIZE WILL INCREASE TOWARD EVENING WHILE STORMS ARE STILL DISCRETE AND BEFORE THE BOUNDARY LAYER BEGINS TO DECOUPLE. ADDITIONAL STORMS WILL LIKELY DEVELOP AS THE FRONT OVERTAKES THE DRYLINE...AND THIS ACTIVITY WILL PROBABLY BEGIN TO GROW UPSCALE AS IT CONTINUES THROUGH ERN OK INTO THE LOWER MS VALLEY OVERNIGHT WHERE THE THREAT FOR DAMAGING WIND MAY ALSO INCREASE.

http://www.spc.noaa.gov/products/outlook/day1otlk.html
..DIAL/COHEN.. 04/14/2011

[venture]

Outlook Map:



Tornado Probability Map:

[venture]

Morning Update...

Red Flag Warning has been issues for all counties in Central and Southwest Oklahoma that are roughly along/south of I-40 and along/west of I-35. A Wind Advisory is also in effect for Western OK. Fire Weather Watch remains for NW Oklahoma.

The dryline isn't firmly established yet, but should be setup with in the next couple of hours along the OK/TX border. Dewpoints in the OK Panhandle and Harper County are starting to decrease compared to areas just east of there.

Short term models continue to move the dryline into Central OK around 5-7PM this afternoon with storms develop along and ahead of it.

[BG918]

Looks like this will be the first severe weather outbreak of the 2011 season. It will be interesting to see where exactly the storms will develop. A little further west and storms could be affecting the OKC metro around rush hour..

[venture]

New Day 1 outlook isn't really all that different. Slight risk shifted a hair further east and the moderate a hair further west.

MODERATE RISK is along and east of a line from 4 mi W of Ponca City to Stillwater to Shawnee to 6 W of Ada to 6 W of Durant.

SLIGHT RISK is along and east of a line from 15 mi W of Medord to Goldsby to 14 W of Ardmore.

[venture]

Short Term model guidance this morning has storms starting between 4 and 6PM almost right along US 177 on the edge of the Moderate Risk area. Some models are further east, one was back to the west more. Things will continue to change through the day.

Dryline is establishing itself very quickly this morning roughly along or just west of US 183 in western Oklahoma. This morning it is moving about 20 mph to the east, but is isn't exactly a solid boundary yet. If it maintains the current speed it would be in OKC in about 5 hours. This would match up pretty good with what the HRRR 12Z run is projecting. It does however apply the breaks to the dryline as soon as it gets here and really tightens the gradient between dewpoints in the 20s and 30s in Canadian/Caddo counties and 60s in Cleveland/McClain/Oklahoma counties. So would not be shocked to see things start right on top of us and then move east. If the dryline hangs up to the west by 25-35 miles, that would raise the severe risk for the Metro Area considerably.

[Jesseda]

thank you venture for your updates, i have said it before and i will say it again, i look on this board for your post before i check the news weather web site..

[venture]

thank you venture for your updates, i have said it before and i will say it again, i look on this board for your post before i check the news weather web site..

Appreciate the feedback. :-)

Update for the hour...low level moisture is pouring in right now, as you can see outside. Low stratus transporting moisture in from the gulf has raised dewpoints into the 60s now from Chandler to Norman to Duncan and to the south and east. Dryline continues to make progress east as it is now moving into Comanche, Caddo, Blaine, Major and Alfalfa counties. Short term models HRRR and RUC all indicate storms forming around 4PM, so no change there. Latest RUC slams the brakes on the dryline once it gets to I-35 or just slight east. So something to watch if it takes place sooner.

At this point the trend continues to have most (if not all) activity east of US 177.

[Thunder]

I hope the dryline stalls west of the metro. We need rain!

[Jesseda]

rain we do need, just keep the tornados and hail away..

[venture]

Update...

Dryline is continues east at about 16-20 mph. It currently is located roughly from Cherokee to Lahoma to just east of Kingfisher to east of El Reno to west of Minco and Chickasha to west of Rush Springs to west of Duncan down to Waurika.

Based on this and continued trends in the models, OKC proper should remain dry and outside of the severe risk. South sections of the Metro (Norman and south) could remain in it a bit longer. Cloud development is best along and east of I-35 at this time.

The other side to this is the rapidly increasing fire danger. Relative humidity is extremely low right now in SW Oklahoma...below 20%. These values will continue to follow the dryline and winds will be 30-40mph most of the afternoon and early evening. Extreme fire danger will spread into the Metro area as we get deeper into the afternoon.