La Niña drawing to a close

By: Dr. Jeff Masters , 3:39 PM GMT on February 27, 2012

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La Niña, the cooling of the equatorial Pacific waters off the coast of South America that has dramatically affected our weather for most of the past two years, is almost done. Sea surface temperatures (SSTs) over the tropical Eastern Pacific in the area 5°N - 5°S, 120°W - 170°W, also called the "Niña 3.4 region", have warmed rapidly over the past two weeks, and were 0.4°C below average on February 27. This is slightly warmer than the -0.5°C threshold to be considered La Niña conditions, and is the first time since early August that La Niña conditions have not been present. It is likely that SSTs will continue to warm during March and April, and NOAA's Climate Prediction Center is predicting that they will declare an official end to La Niña sometime between March and April. A moderate to strong La Niña began in the summer of 2010, weakened briefly during May - July 2011 to neutral status, then re-intensified to a borderline weak/moderate La Niña from August 2011 - January 2012.


Figure 1. Comparison of the sea surface temperature departure from average from January 4 and February 22, 2012, over the tropical Eastern Pacific. During January, a large region of the ocean was more than 0.5°C cooler than average, meaning a La Niña event was present. Beginning in mid-February, waters warmed rapidly from east to west along the Equator, signaling and end to the La Niña event. Image credit: NOAA.

The forecast: neutral or El Niño conditions by fall
The period March - May is the typical time of year that El Niño or La Niña events end, and it is common for the opposite phenomena to take hold by fall. Since 1950, there have been twelve La Niña events that ended during the first half of the year; during six of those years (50%), an El Niño event formed in time for the August - September - October peak of hurricane season. The official forecast from Columbia University's IRI and NOAA's Climate Prediction Center calls for a 31 - 32% chance of an El Niño event during the 2012 Atlantic hurricane season. El Niño conditions tend to suppress Atlantic hurricane activity by creating high levels of wind shear that tends to tear hurricanes apart. Given the relatively high chance of an El Niño event this fall, plus ocean temperatures over the tropical Atlantic that are cooler than we saw in 2011 and 2010, I doubt we'll see an Atlantic hurricane season as active as the ones in 2010 and 2011 (nineteen named storms both years, third busiest seasons on record.) The demise of La Niña also means that global temperatures should begin to approach record warm levels by the end of the year. The cool waters of a La Niña event keep global temperatures cooler than average.


Figure 2. Computer model forecasts of El Niño/La Niña made in mid-February 2012. The forecasts that go above the red line at +0.5°C denote El Niño conditions; -0.5°C to +0.5°C denote neutral conditions, and below -0.5°C denote La Niña conditions. Most of the computer models are predicting neutral or El Niño conditions during the fall peak of the Atlantic hurricane season. Image credit: Columbia University's IRI.

I'll have a new post by Wednesday.

Jeff Masters

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578. HadesGodWyvern (Mod)
Mauritius Meteorological Services
Tropical Cyclone Advisory #1
PERTURBATION TROPICALE 12-20112012
4:00 AM RET February 29 2012
==============================

At 0:00 AM UTC, Tropical Disturbance 12 (999 hPa) located at 12.5S 69.2E has 10 minute sustained winds of 25 knots with gusts of 40 knots. The disturbance is reported as moving south at 3 knots.

Dvorak Intensity: T2.0/2.0/D0.5/12 HRS

Forecast and Intensity
==============

12 HRS: 13.3S 69.1E - 30 knots (Depression Tropicale)
24 HRS: 14.5S 68.2E - 30 knots (Depression Tropicale)
48 HRS: 16.6S 67.7E - 30 knots (Depression Tropicale)
72 HRS: 19.0S 68.8E - 35 knots (Tempête Tropicale Modérée)

Additional Information
================

Since 1800 PM UTC, deep convective activity has consolidated near the center and organized on a curved band pattern. SSMI F15 2310 PM UTC confirms this better feature. Low level inflow improves on the both sides and easterly vertical wind shear has temporarily weakened but is forecast to enforce back today late and tomorrow Thursday. Numerical weather prediction models are now in good agreement to forecast a globally southwards motion. Over this expected track, environmental conditions should become favorable on Friday under the upper level ridge but a new northerly vertical wind shear constraint should established on and after Saturday. Potential for intensification is therefore limited at short or medium range.

The next tropical cyclone advisory from Mauritius Meteorological Services will be issued at 6:30 AM UTC..
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577. HadesGodWyvern (Mod)
Seychelles Meteorological Services
Tropical Cyclone Advisory #7
DEPRESSION TROPICALE, FORMER IRINA (11-20112012)
4:00 AM RET February 29 2012
=====================================

At 0:00 AM UTC, Tropical Depression, Former Irina (994 hPa) located at 16.3S 43.4E has 10 minute sustained winds of 30 knots with gusts of 45 knots. The cyclone is reported as moving west at 4 knots.

Near Gale Force Winds
=============
30 NM radius from the center extending up to 45 NM in the northwestern quadrant

Dvorak Intensity: T2.5/2.5/S0.0/0 HRS

Forecast and Intensity
========================

12 HRS: 16.7S 42.9E - 35 knots (Tempête Tropicale Modérée)
24 HRS: 17.3S 42.6E - 40 knots (Tempête Tropicale Modérée)
48 HRS: 20.3S 41.2E - 60 knots (Forte Tempête Tropicale)
72 HRS: 22.4S 38.0E - 80 knots (Cyclone Tropical)

Additional Information
=======================

Low level circulation center remains very difficult to precisely localize. Deep convective activity enforces and organizes in a curved band pattern in the west of the estimated center. Most of available numerical weather prediction models are in good agreement. System is expected to track globally southwest on the northwestern edge of the subtropical ridge. Vertical wind shear keeps on weakening aloft as previously forecast allowing the system to intensify. On Wednesday and Thursday, the very good equatorward upper level outflow is expected to combine to a strong poleward one, environmental conditions should progressively improve and become favorable for significant further re-intensification. An oversea track in the middle of the channel within this favorable environment should allow the system to reach tropical cyclone stage on Friday.

Available numerical weather prediction forecast tracks are in good agreement to a landfall on the Mozambique coastline. The potential threatened areas remains difficult at this range to be precisely targeted but runs after runs concentrates in a region between Beira and Maputo.

The next tropical cyclone advisory on TC Irina from Seychelles Meteorological Services will be issued at 6:30 AM UTC..
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Quoting TheOnlyBravesFan:


Prinzsessin on na13, was given a duke on na15 turned it into a prinzessin, both were top 200 players, had 12's, 14's and hh's on both. Over 4 mil prestige on both accounts before quitting. =)


.....nice.....i didnt play for about 5 months tho lol.

I had a tough road as i was growing, seemed like every single person HAD to attack me. but i figured that brains was better then force and didnt get conquered teehee:D

Member Since: August 4, 2011 Posts: 46 Comments: 4488
WW 41

Probability of two or more tornadoes: Mod 40%

Probability of one or more strong tornadoes: Mod 30%
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Quoting WDEmobmet:




Dont know if anyone has posted about this...but it appears there is a fairly large rotation with this tornadic cell fixing to roll through Council Grove,Kansas
What are you using for your Level 2 data source?
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On my previous post i changed showsevere to =1, and it put the radar elevated and the severe lines on the ground instead of the usual opposite
Member Since: February 11, 2012 Posts: 0 Comments: 9738
Quoting SPLbeater:


Category 4(likely a 5) Hurricane Igor 2010!


the deadliest C5 Mitch
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We have Tropical Cyclone Irina!! forecast to become a nice cyclone :D
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Quoting interstatelover7165:
Now I raise you all a question: what is your favorite hurricane, ever?


Category 4(likely a 5) Hurricane Igor 2010!
Member Since: August 4, 2011 Posts: 46 Comments: 4488
Quoting SPLbeater:


i did NOT pay, and got up to 1.8M prestige on na31 due to 350k archers. had a Baron title...and started farming 10's. but then me and my girlfriend's flame went out, and i quit.


Prinzsessin on na13, was given a duke on na15 turned it into a prinzessin, both were top 200 players, had 12's, 14's and hh's on both. Over 4 mil prestige on both accounts before quitting. =)
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Dont know if anyone has posted about this...but it appears there is a fairly large rotation with this tornadic cell fixing to roll through Council Grove,Kansas
Member Since: February 3, 2010 Posts: 0 Comments: 755
Now I raise you all a question: what is your favorite hurricane, ever?
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off topic.
yesterday Feb 27 was the 2nd anniversary of the deadly Chile quake/tsunami
Shall say RIP for those who left


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Quoting WxGeekVA:


Well, I got Prinzezzin on 2 servers and was ranked #40 on NA35 before I quit.... I had over 50k catapults at one point.

I paid though, almost $200.... I got addicted.


i did NOT pay, and got up to 1.8M prestige on na31 due to 350k archers. had a Baron title...and started farming 10's. but then me and my girlfriend's flame went out, and i quit.
Member Since: August 4, 2011 Posts: 46 Comments: 4488
storms about to leave watch. New MD coming soon probably, or new watch.
Member Since: February 11, 2012 Posts: 0 Comments: 9738
Quoting GeorgiaStormz:


Who has enough time for evony?
Or enough money?
Without these 2, you dont have a shot.


Yes, the game does require quite a bit of time. No less than 4 hrs a day!

Money: If you play well enough, you won't need to spend money. I was pretty good on my server without spending money for gears/hero upgrades. Money is a great help though.
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http://grist.org/climate-change/what-left-and-rig ht-really-mean-on-climate-change-hint-nothing/

It's a mess. There really is no coherent left vs. right on climate, at least not in terms of economic ideology.

But that just goes to show that the real battles around climate have nothing to do with principles of governance. The central battle, the one that shapes all others, is the one between those aligned with the status quo - fossil-fuel development, sprawl, and unfettered carbon pollution - and those who seek to change it. There is nothing "left" or "right" about the status quo, it's simply a set of rigged rules and institutions meant to support certain financial interests. Commitment to preserving the privileges and advantages of status quo interests is not a philosophy at all. It does not submit to placement on an ideological spectrum. (It is thus a dark irony that the term used to describe those most committed to this purely instrumental approach to governance is "Centrists.")

There are other sub-battles: The battle over science and education. The battle over communications and framing. The battle over activism and its targets. But these are fights over epistemology, psychology, and social change - none of them divide neatly into left and right. The terms "liberal" and "conservative" are often used around climate, but they are used in a purely tribal sense, to designate some group or coalition. In actual fact, there is no struggle between philosophies happening in U.S. climate politics, only a struggle among economic interests.
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Quoting GeorgiaStormz:


Who has enough time for evony?
Or enough money?
Without these 2, you dont have a shot.


Well, I got Prinzezzin on 2 servers and was ranked #40 on NA35 before I quit.... I had over 50k catapults at one point.

I paid though, almost $200.... I got addicted.
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Quoting SPLbeater:
IM BACK



judging by your avatar, you play(ed) evony age 2?


Yes, I did, without paying for the most part too. Only spent $10 one time.

Quit for now (finally quit na13, previously played na15,na22, and na23). Next time I play, I will be paying big time though, need that great gear/stars.

But back to the topic at hand...

KSC017-115-290230-
/O.CON.KICT.TO.W.0004.000000T0000Z-120229T0230Z/
MARION KS-CHASE KS-
801 PM CST TUE FEB 28 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN CHASE AND
EAST CENTRAL MARION COUNTIES UNTIL 830 PM CST...

AT 755 PM CST...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
STORM WAS LOCATED NEAR LINCOLNVILLE...OR 10 MILES NORTHEAST OF
MARION...MOVING NORTHEAST AT 55 MPH.

THIS STORM HAS A HISTORY OF PRODUCING BRIEF TORNADO TOUCHDOWNS ALONG
WITH GOLFBALL SIZE HAIL.

LOCATIONS IMPACTED INCLUDE...
ELMDALE AND HYMER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN WICHITA.
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Quoting GeorgiaStormz:


Who has enough time for evony?
Or enough money?
Without these 2, you dont have a shot.


i never paid, and i was a fortress on na31. lots of my friends feared me lol
Member Since: August 4, 2011 Posts: 46 Comments: 4488
looks like emporia may be in the path now
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Quoting WxGeekVA:


Well I did, you did SPL, and I guess they do.... Seems like Weather and Evony go well together!


Who has enough time for evony?
Or enough money?
Without these 2, you dont have a shot.
Member Since: February 11, 2012 Posts: 0 Comments: 9738
Quoting SPLbeater:
IM BACK



judging by your avatar, you play(ed) evony age 2?


Well I did, you did SPL, and I guess they do.... Seems like Weather and Evony go well together!
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IM BACK

Quoting TheOnlyBravesFan:
Pretty cool looking storms, blossomed quickly, and this is only the beginning.


judging by your avatar, you play(ed) evony age 2?
Member Since: August 4, 2011 Posts: 46 Comments: 4488
Quoting hurricanehunter27:
NOOOOO!!!
Link



DRAMATIC BIEBER!!!
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Pretty cool looking storms, blossomed quickly, and this is only the beginning.
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Quoting WxGeekVA:


I'll see your DRAMATIC CAT and raise you a:



DARTHMATIC CHIPMUNK!!!
NOOOOO!!!
Link
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Link
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Quoting Articuno:

More like a:


DRAMATIC CAT!!!!!!!!!!!


I'll see your DRAMATIC CAT and raise you a:



DARTHMATIC CHIPMUNK!!!
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Can someone provide a level2 source for analyst?
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The line doesn't seem quite connected, individual supercells seem to be splitting off.
Also, the snow is almost to where the 1st tornado of the day was.
Member Since: February 11, 2012 Posts: 0 Comments: 9738
7 pm CDT Day 1 Convective Outlook



DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0700 PM CST TUE FEB 28 2012

VALID 290100Z - 291200Z

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

...CNTRL AND SRN PLAINS/OZARKS/MID MS VALLEY...
A SEVERE WEATHER EVENT IS UNDERWAY ACROSS THE CNTRL PLAINS ALONG AND
TO THE EAST OF A DRYLINE EXTENDING FROM JUST WEST OF SALINA KS SWD
INTO WRN OK. AN UPPER-LEVEL TROUGH IS MOVING THROUGH THE CNTRL HIGH
PLAINS WITH AN 85 TO 100 KT MID-LEVEL JET LOCATED IN THE BASE OF THE
TROUGH. THE EXIT REGION OF THE MID-LEVEL JET IS OVERSPREADING THE
CNTRL PLAINS WHICH IS ENHANCING LIFT AND CREATING A STRONGLY SHEARED
ENVIRONMENT FAVORABLE FOR SEVERE STORMS
. THE THUNDERSTORMS IN CNTRL
KS SHOULD CONTINUE TO MOVE ENEWD INTO THE OMAHA AND KANSAS CITY
AREAS THIS EVENING WHERE A LARGE HAIL THREAT WILL EXIST WITH THE
MORE INTENSE CELLS DUE TO THE STRONG SHEAR AND STEEP MID-LEVEL LAPSE
RATES. IN ADDITION...REGIONAL WSR-88D VWPS IN ECNTRL KS SHOW 0-3 KM
STORM RELATIVE HELICITIES IN THE 450 TO 600 M2/S2 RANGE WHICH SHOULD
SUPPORT SUPERCELL AND TORNADO DEVELOPMENT. FOR THIS REASON...HAVE
EXTENDED THE 5 PERCENT TORNADO PROBABILITY NWWD ACROSS MUCH OF ERN
KS INTO FAR SE NEB.


AS THE UPPER-LEVEL SYSTEM MOVES NEWD ACROSS THE CNTRL PLAINS THIS
EVENING...A COLD FRONT WILL OVERTAKE THE DRYLINE AND ADVANCE EWD
ACROSS ERN NEB...ERN KS AND CNTRL OK. THUNDERSTORM DEVELOPMENT
SHOULD OCCUR JUST AHEAD OF THE BOUNDARY WITH A BROKEN LINE OF
ORGANIZED THUNDERSTORMS DEVELOPING DURING THE MID TO LATE EVENING.
STRONG MOISTURE ADVECTION AND DESTABILIZATION ASSOCIATED WITH A
EXPANDING LOW-LEVEL JET SHOULD KEEP THE SEVERE THREAT GOING LATE
THIS EVENING INTO THE OVERNIGHT PERIOD. WELL AHEAD OF THE FRONT IN
NRN AR AND SRN MO...MODEL FORECASTS SHOW AN IMPRESSIVE SHEAR
ENVIRONMENT AFTER MIDNIGHT WITH LOOPING HODOGRAPHS AND 0-3 KM STORM
RELATIVE HELICITIES IN THE 400 TO 500 M2/S2 RANGE. THIS SHOULD
SUPPORT THE DEVELOPMENT OF TORNADIC SUPERCELLS ESPECIALLY AS SFC
DEWPOINTS IN NRN AR INCREASE INTO THE LOWER 60S F AFTER MIDNIGHT. AN
ISOLATED STRONG TORNADO COULD OCCUR NEAR THE AR-MO STATE-LINE AND
NEAR THE MO BOOTHEEL
AS STORMS INCREASE IN COVERAGE AND AS LOW-LEVEL
SHEAR BECOMES MORE FAVORABLE LATE TONIGHT. A WIND DAMAGE THREAT
SHOULD ALSO EXIST ESPECIALLY IF A LINEAR MCS CAN ORGANIZE AND
PERSIST DURING THE OVERNIGHT PERIOD WITH THIS THREAT MOVING INTO WRN
KY AND SRN IL LATE.

..BROYLES.. 02/29/2012
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Quoting WxGeekVA:


That deserves a:




DRAMATIC CHIPMUNK!!!!

More like a:


DRAMATIC CAT!!!!!!!!!!!
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Ok this is about to drop something massive.
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Man this cell got serious...strong rotation.
Member Since: July 6, 2010 Posts: 113 Comments: 32565
Quoting TropicalAnalystwx13:
Interesting twist to tornado warning.

"THE TORNADIC POTENTIAL OF THIS SEVERE THUNDERSTORM IS ONCE AGAIN INCREASING!"
Yah its really starting to get its act together, glad they included that.
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Quoting Articuno:

IT'S A........SNOWNADO???
:\


Like it!

New mesoscale discussion up about the kansas/oklahoma storms... threat for WW40 continues.



MESOSCALE DISCUSSION 0170
NWS STORM PREDICTION CENTER NORMAN OK
0716 PM CST TUE FEB 28 2012

AREAS AFFECTED...S-CNTRL/SERN KS...N-CNTRL OK

CONCERNING...TORNADO WATCH 40...

VALID 290116Z - 290245Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 40 CONTINUES.

INITIAL DISCRETE SUPERCELL WITH A HISTORY OF PERIODIC BRIEF TORNADO
TOUCHDOWNS WILL BE THE PRIMARY NEAR-TERM SEVERE THREAT INVOF
RENO/HARVEY/MCPHERSON COUNTIES KS. ADDITIONAL TSTM DEVELOPMENT
APPEARS TO BE UNDERWAY AS COLD FRONT HAS OVERTAKEN THE DRYLINE INTO
NWRN OK. ALTHOUGH CONVECTION SHOULD TRANSITION TO A LARGELY LINEAR
MODE...VERY STRONG SHEAR WILL BE FAVORABLE FOR AN INCREASING RISK OF
DAMAGING WINDS...WITH PERHAPS AN ADDITIONAL TORNADO OR TWO. A NEW WW
MAY BE NEEDED FOR PARTS OF OK.

01Z SURFACE ANALYSIS INDICATES THE PACIFIC COLD FRONT HAS OVERTAKEN
THE DRYLINE ACROSS CNTRL KS INTO FAR NWRN OK...RESULTING IN A
SUBSTANTIAL INCREASE IN CONVERGENCE. THIS HAS YIELDED A RAPID
INCREASE IN TSTM COVERAGE ALONG THE BOUNDARY. MEANWHILE...A COUPLE
OF DISCRETE STORMS HAVE PERSISTED AHEAD OF THE DRYLINE INVOF HUT.
ALTHOUGH THE 00Z OUN RAOB WAS QUITE CAPPED...MODIFIED TOP RAOB
SUGGESTS INSTABILITY IS WEAK /MLCAPE NEAR 500 J/KG/ BUT SUFFICIENT
FOR TORNADO AND DAMAGING WIND THREATS GIVEN PRESENCE OF EFFECTIVE
SRH AOA 400 M2/S2. CONTINUED BOUNDARY LAYER MOIST ADVECTION SHOULD
SUPPORT THESE RISKS WITHIN ONE OR MORE PROBABLE LINE-SEGMENTS
PROPAGATING QUICKLY E/SEWD THIS EVENING.

..GRAMS.. 02/29/2012


ATTN...WFO...TSA...TOP...ICT...OUN...DDC...

LAT...LON 37609859 37949833 38439760 38609683 38669600 38429574
37449580 36669616 35969656 35729739 35899852 36349887
37609859
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Interesting twist to tornado warning.

"THE TORNADIC POTENTIAL OF THIS SEVERE THUNDERSTORM IS ONCE AGAIN INCREASING!"
Member Since: July 6, 2010 Posts: 113 Comments: 32565
MESOSCALE DISCUSSION 0170
NWS STORM PREDICTION CENTER NORMAN OK
0716 PM CST TUE FEB 28 2012

AREAS AFFECTED...S-CNTRL/SERN KS...N-CNTRL OK

CONCERNING...TORNADO WATCH 40...

VALID 290116Z - 290245Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 40 CONTINUES.

INITIAL DISCRETE SUPERCELL WITH A HISTORY OF PERIODIC BRIEF TORNADO
TOUCHDOWNS WILL BE THE PRIMARY NEAR-TERM SEVERE THREAT INVOF
RENO/HARVEY/MCPHERSON COUNTIES KS
. ADDITIONAL TSTM DEVELOPMENT
APPEARS TO BE UNDERWAY AS COLD FRONT HAS OVERTAKEN THE DRYLINE INTO
NWRN OK. ALTHOUGH CONVECTION SHOULD TRANSITION TO A LARGELY LINEAR
MODE...VERY STRONG SHEAR WILL BE FAVORABLE FOR AN INCREASING RISK OF
DAMAGING WINDS...WITH PERHAPS AN ADDITIONAL TORNADO OR TWO. A NEW WW
MAY BE NEEDED FOR PARTS OF OK
.

01Z SURFACE ANALYSIS INDICATES THE PACIFIC COLD FRONT HAS OVERTAKEN
THE DRYLINE ACROSS CNTRL KS INTO FAR NWRN OK...RESULTING IN A
SUBSTANTIAL INCREASE IN CONVERGENCE. THIS HAS YIELDED A RAPID
INCREASE IN TSTM COVERAGE ALONG THE BOUNDARY. MEANWHILE...A COUPLE
OF DISCRETE STORMS HAVE PERSISTED AHEAD OF THE DRYLINE INVOF HUT
.
ALTHOUGH THE 00Z OUN RAOB WAS QUITE CAPPED...MODIFIED TOP RAOB
SUGGESTS INSTABILITY IS WEAK /MLCAPE NEAR 500 J/KG/ BUT SUFFICIENT
FOR TORNADO AND DAMAGING WIND THREATS GIVEN PRESENCE OF EFFECTIVE
SRH AOA 400 M2/S2. CONTINUED BOUNDARY LAYER MOIST ADVECTION SHOULD
SUPPORT THESE RISKS WITHIN ONE OR MORE PROBABLE LINE-SEGMENTS
PROPAGATING QUICKLY E/SEWD THIS EVENING.


..GRAMS.. 02/29/2012
(8:10 cdt - Grpahic now available - added)
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Quoting Ameister12:

Will the storms be more linear or be could we see some supercells with the E. Oklahoma and Arkansas storms.

Supercellular eventually transitioning into linear.
Member Since: July 6, 2010 Posts: 113 Comments: 32565
Quoting TropicalAnalystwx13:

Storms are switching from a supercellular mode to a linear mode. This means that the tornado threat is lesser than earlier, but still existent.

The main Severe Weather event has yet to initiate...this will occur across Eastern Oklahoma and Arkansas as favorable thermodynamics move to the east and the cap breaks.

I'm surprised the cell we have been watching is still holding up, looks like it might want to drop another tornado.
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Quoting TropicalAnalystwx13:

Storms are switching from a supercellular mode to a linear mode. This means that the tornado threat is lesser than earlier, but still existent.

The main Severe Weather event has yet to initiate...this will occur across Eastern Oklahoma and Arkansas as favorable thermodynamics move to the east and the cap breaks.


Will the storms be more linear or be could we see some supercells with the E. Oklahoma and Arkansas storms.
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527. CosmicEvents 12:57 AM GMT on February 29, 2012

barf!
***

Quoting TropicalAnalystwx13:


Sorry, I haven't been watching radar. Is that the same cell that went near Hutchinson, KS picking up again? (graphic at comment 532.)
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Quoting KEEPEROFTHEGATE:

Storms are switching from a supercellular mode to a linear mode. This means that the tornado threat is lesser than earlier, but still existent.

The main Severe Weather event has yet to initiate...this will occur across Eastern Oklahoma and Arkansas as favorable thermodynamics move to the east and the cap breaks.

Member Since: July 6, 2010 Posts: 113 Comments: 32565
Member Since: July 15, 2006 Posts: 175 Comments: 54893
Member Since: July 15, 2006 Posts: 175 Comments: 54893
Member Since: July 6, 2010 Posts: 113 Comments: 32565
Quoting TropicalAnalystwx13:
The first February Nebraska tornado on record...snow is still on the ground, and temperature was 47F.


IT'S A........SNOWNADO???
:\
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MESOSCALE DISCUSSION 0169
NWS STORM PREDICTION CENTER NORMAN OK
0703 PM CST TUE FEB 28 2012

AREAS AFFECTED...S-CNTRL NEB AND N-CNTRL KS

CONCERNING...TORNADO WATCH 39...

VALID 290103Z - 290230Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 39 CONTINUES.

MODEST SFC BASED INSTABILITY COMBINED WITH FAVORABLE VERTICAL SHEAR
PROFILES JUST AHEAD OF A DRYLINE/COLD FRONT WILL ALLOW THE SEVERE
THREAT TO CONTINUE ACROSS CENTRAL AND EASTERN PORTIONS OF WW 39 THE
NEXT COUPLE OF HOURS. LATEST SFC ANALYSIS INDICATED A COLD FRONT
EXTENDING FROM NEAR BBW TO MCK SWWD TO JUST E OF GLD. THE DRYLINE
WAS STILL SOMEWHAT AHEAD OF THE COLD FRONT EXTENDING SWD FROM BBW TO
NEAR HDE TOWARD HYS. IT WAS ALONG THE DRYLINE IN A NARROW WARM
SECTOR THAT THUNDERSTORMS WERE CONTINUING TO DEVELOP AND MAINTAIN
SEVERE CHARACTERISTICS FROM TIME TO TIME. WHILE THE THREAT MAY BE
TRANSITIONING TO MORE OF A DAMAGING WIND/HAIL THREAT AS STORMS TAKE
ON MORE OF A LINEAR MODE...GIVEN THE INTENSE LOW LEVEL SHEAR A
TORNADO OR TWO STILL CAN NOT BE RULED OUT THROUGH 03Z.

WHILE STORMS NEAR THE EASTERN EDGE OF THE WW HAVE PREVIOUSLY SHOWED
SEVERE CHARACTERISTICS...THEY HAVE SINCE WEAKENED AND A WATCH
DOWNSTREAM IS NOT CURRENTLY ANTICIPATED BUT TRENDS WILL BE
MONITORED.

..LEITMAN.. 02/29/2012

(8:12 cst Graphic now available - added)

***

Storm reports
2213 9 WSW GANDY LOGAN NE4142 10062
OFF DUTY NWS EMPLOYEE REPORTED A TORNADO 9 MILES WSW OF GANDY. (LBF)

0007 UNK BELLEVILLE REPUBLIC KS 3982 9763 POWER LINES DOWN IN BELLEVILLE. (TOP)

0043 6 SSW HUTCHINSON RENO KS 3799 9796
STORM CHASER REPORTED A TORNADO LASTING ABOUT 5 MINUTES FROM 643 TO 648 PM. (ICT)

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Here we go again:
Member Since: February 11, 2012 Posts: 0 Comments: 9738
Quoting GeorgiaStormz:


Possible Tornado


That's just a wall cloud, imo.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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