Jump to content
  • Member Statistics

    17,603
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

August 12-? Severe Weather


Recommended Posts

  • Replies 256
  • Created
  • Last Reply

Although we are still far out, parameters are looking pretty nasty next week (particularly the 174 hr GFS) into the Northern Plains (mainly SD) into Minnesota, with an impulse ejecting eastward ahead of the main Canadian trough along with some really nice theta-e and 35-50 kt southwesterly/westerly flow at 500mb feeding into the area. A warm EML layer may easily disrupt this like the previous several in the Northern Plains, however...

Link to comment
Share on other sites

Although we are still far out, parameters are looking pretty nasty next week (particularly the 174 hr GFS) into the Northern Plains (mainly SD) into Minnesota, with an impulse ejecting eastward ahead of the main Canadian trough along with some really nice theta-e and 35-50 kt southwesterly/westerly flow at 500mb feeding into the area. A warm EML layer may easily disrupt this like the previous several in the Northern Plains, however...

too early to get into details about wind speeds at 174hr.....

Link to comment
Share on other sites

Once again right in baro's backyard, wonder if he'll make the trip...

Edit: New day 1 agrees with you, rather large 5% tornado/30% wind/30% sig-hail across NE and SD.

Also, look at this...

DAY 2 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1209 AM CDT THU AUG 11 2011

VALID 121200Z - 131200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PORTION OF THE CNTRL AND

SRN PLAINS THROUGH MID-LOWER MS VALLEY...

...SYNOPSIS...

VORT MAX NOW OVER WA STATE WILL CONTINUE THROUGH THE N-CNTRL PLAINS

AND MID-UPPER MS VALLEY REGION FRIDAY. QUASI-STATIONARY BAROCLINIC

ZONE WILL PERSIST FROM SERN STATES WNWWD INTO THE LOWER MS VALLEY

AND OK/KS. COLD FRONT ACCOMPANYING THE UPPER TROUGH WILL ADVANCE

THROUGH THE NRN-CNTRL PLAINS AND UPPER MS VALLEY DURING THE DAY.

...PORTIONS OF CNTRL/SRN PLAINS AND MID-LOWER MS VALLEY AREAS...

RESERVOIR OF RICHER LOW LEVEL MOISTURE WILL PERSIST IN VICINITY OF

BAROCLINIC ZONE AND WILL BEGIN TO ADVECT NWD AS BOUNDARY LAYER FLOW

BECOMES SELY EAST OF CNTRL HIGH PLAINS LEE TROUGH. WLY FLOW ALOFT

WILL MAINTAIN EML PLUME WITH STEEPER LAPSE RATES ABOVE THE MOIST

BOUNDARY LAYER OVER THE PLAINS. THIS WILL RESULT IN POTENTIAL FOR

MODERATE-STRONG MLCAPE FROM NRN OK THROUGH CNTRL PLAINS AND

MID-LOWER MS VALLEY. PRIMARY COMPLICATING FACTOR CONTINUES TO BE

LIKELIHOOD ONGOING STORMS FRIDAY MORNING...AND INDICATIONS ARE THAT

STORMS MAY BE IN PROGRESS NORTH OF FRONT WITHIN ZONE OF ISENTROPIC

ASCENT ON NOSE OF SSWLY LLJ FROM ERN NEB THROUGH A PORTION OF ERN KS

AND MID MS VALLEY. DIABATIC WARMING SHOULD DESTABILIZE THE BOUNDARY

LAYER SOUTH OF THIS ACTIVITY...AND STORMS MAY INTENSIFY AND

REDEVELOP ALONG PRE-EXISTING OUTFLOW BOUNDARIES AND BAROCLINIC ZONE.

ADDITIONAL STORMS SHOULD DEVELOP ALONG SEWD ADVANCING COLD FRONT.

MID LEVEL JET ALONG BASE OF SHORTWAVE TROUGH WILL RESULT IN 35-45 KT

EFFECTIVE SHEAR OVER MUCH OF THIS AREA WITH POTENTIAL FOR BOWING

SEGMENTS AND SUPERCELLS AS WELL AS EVOLUTION INTO MCS CLUSTERS.

DAMAGING WIND AND LARGE HAIL WILL BE THE MAIN THREATS THROUGH THE

EVENING.

..DIAL.. 08/11/2011

Link to comment
Share on other sites

Once again right in baro's backyard, wonder if he'll make the trip...

Edit: New day 1 agrees with you, rather large 5% tornado/30% wind/30% sig-hail across NE and SD.

Also, look at this...

Working. It will be another busy day of severe weather tomorrow...

Tonight was a little surprise in terms of the severe activity across the northern portion of the CWA.

Link to comment
Share on other sites

I'd be watching good ole Cherry county NE tomorrow if I were out chasing, just glancing at the 0z runs. A nice WNW mid-level jet around 40kts or so and the LLJ gets cranking after 0z which helps to low-level shear. Anything can stay discrete till that gets going, it might be worth the trip for anyone out.

Tomorrow is going to be very interesting. For Nebraska looks more like an April/May setup than late August with the afternoon dryline bulge. In all honesty, I think the late arriving upper wave will keep dryline activity isolated...combined with the relatively low LCL-LFC RH's expected. Looks to ramp up during the evening as the aforementioned upper wave begins to eject and large scale forcing for ascent/increasingly divergent straight jet max combines with nocturnal cooling to support a decent nocturnal/dynamic LLJ. Ongoing DMC will likely develop into organized clusters with the inverted V low levels. Big hailers will likely transition to more of a wind threat although the supercells will also likely yield possible significant wind. Effective shear will be pretty darned impressive...in excess of 55-60 knots. Significant instability (2000-2500 MLCAPE) combined with the impressive shear yields a nice Bulk Richardson number tomorrow. Going to be an interesting day. Personally I am getting sick of severe weather, but I am interested in seeing how the events of tomorrow unfold. Like any severe event there will be surprises.

Link to comment
Share on other sites

New Day 2 has a hatched area in much of central/eastern Kansas, southwest Missouri, northwest Arkansas and northeast Oklahoma--and introduces the severe risk here in central Illinois just in time for the start of the Illinois State Fair here in Springfield:

http://www.spc.noaa....k/day2otlk.html

Two years ago the Wednesday of the State Fair--Aug. 19, 2009--was the day of the EF3 Williamsville tornado (and I vividly recall reports of the funnel clouds which eventually spawned that storm to be briefly over the State Fairgrounds on the north side of Springfield). Also Manchester (Morgan County south of Jacksonville) and Loami (southwest of Springfield) were among those hit--Loami for the second time in 2009 (they had also been hit that Mar. 8) and the third time since 2006 (they were also hit hard in the March 12, 2006 tornado outbreak which eventually slammed the south and east parts of Springfield). Lincoln NWS writeup below:

http://www.crh.noaa.gov/ilx/?n=19aug09

Here's the link to Eastern's coverage of the Aug. 19, 2009 Midwest tornado outbreak--including Williamsville and Loami in central Illinois:

http://www.easternuswx.com/bb/index.php?/topic/203626-819-severe-weather-threat/

Then severe weather/heavy rain hit again last year on the Friday nights of the State Fair too--washing out the Lady Antebellum concert that was heavy hyped and promoted for that first Friday night.

I only wonder what 2011 has in store.

Link to comment
Share on other sites

Two years ago the Wednesday of the State Fair--Aug. 19, 2009--was the day of the EF3 Williamsville tornado (and I vividly recall reports of the funnel clouds which eventually spawned that storm to be briefly over the State Fairgrounds on the north side of Springfield). Also Manchester (Morgan County south of Jacksonville) and Loami (southwest of Springfield) were among those hit--Loami for the second time in 2009 (they had also been hit that Mar. 8) and the third time since 2006 (they were also hit hard in the March 12, 2006 tornado outbreak which eventually slammed the south and east parts of Springfield). Lincoln NWS writeup below:

http://www.crh.noaa.gov/ilx/?n=19aug09

Here's the link to Eastern's coverage of the Aug. 19, 2009 Midwest tornado outbreak--including Williamsville and Loami in central Illinois:

http://www.easternus...weather-threat/

I saw that tornado, not till it was near Elkhart though, did pretty major damage to a families barn and house.

Link to comment
Share on other sites

New Day 2 has a hatched area in much of central/eastern Kansas, southwest Missouri, northwest Arkansas and northeast Oklahoma--and introduces the severe risk here in central Illinois just in time for the start of the Illinois State Fair here in Springfield:

http://www.spc.noaa....k/day2otlk.html

Two years ago the Wednesday of the State Fair--Aug. 19, 2009--was the day of the EF3 Williamsville tornado (and I vividly recall reports of the funnel clouds which eventually spawned that storm to be briefly over the State Fairgrounds on the north side of Springfield). Also Manchester (Morgan County south of Jacksonville) and Loami (southwest of Springfield) were among those hit--Loami for the second time in 2009 (they had also been hit that Mar. 8) and the third time since 2006 (they were also hit hard in the March 12, 2006 tornado outbreak which eventually slammed the south and east parts of Springfield). Lincoln NWS writeup below:

http://www.crh.noaa.gov/ilx/?n=19aug09

Here's the link to Eastern's coverage of the Aug. 19, 2009 Midwest tornado outbreak--including Williamsville and Loami in central Illinois:

http://www.easternus...weather-threat/

Then severe weather/heavy rain hit again last year on the Friday nights of the State Fair too--washing out the Lady Antebellum concert that was heavy hyped and promoted for that first Friday night.

I only wonder what 2011 has in store.

I remember that event very well, we were at the fair.

As for tomorrow, I hope we can get a nice soaking rain, the soybeans need it bad around here. Don't need the severe though because the corn is 10ft tall and it would all go down with a little wind. It does look like our best chance for rain in three weeks though.

Link to comment
Share on other sites

URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 766

NWS STORM PREDICTION CENTER NORMAN OK

310 PM CDT THU AUG 11 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

SOUTH DAKOTA

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 310 PM UNTIL

1000 PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 75 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 140 STATUTE

MILES EAST AND WEST OF A LINE FROM 75 MILES NORTH NORTHEAST OF

PIERRE SOUTH DAKOTA TO 75 MILES SOUTH SOUTHEAST OF PHILIP SOUTH

DAKOTA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED

WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).

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.

DISCUSSION...STRONG STORMS HAVE DEVELOPED OVER WEST CENTRAL SD...AND

ADDITIONAL CONVECTION IS LIKELY TO DEVELOP AND INTENSIFY THIS

AFTERNOON AS A SHORT WAVE TROUGH MOVES EWD FROM MT. IN RESPONSE TO

THE APPROACHING TROUGH...THE LOW LEVEL JET IS BEGINNING TO

STRENGTHEN /30 KT AT KLBF RDA/ AND THIS IS FORECAST BY MODELS TO

LIFT NWD INTO SRN SD BY LATE THIS AFTERNOON. WINDS WILL INCREASE

AND VEER WITH HEIGHT PROVIDING A FAVORABLE KINEMATIC ENVIRONMENT FOR

SEVERE STORMS INCLUDING SUPERCELLS. STRONGER CELLS WILL HAVE

POTENTIAL TO PRODUCE VERY LARGE HAIL...DAMAGING WIND...AND A FEW

TORNADOES. THE CONVECTION IS EXPECTED TO GROW UPSCALE AND FORM INTO

A SEWD MOVING BOWING QLCS BY THIS EVENING WITH AN INCREASING THREAT

FOR DAMAGING WIND GUSTS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

550. MEAN STORM MOTION VECTOR 28025.

...WEISS

Link to comment
Share on other sites

Possible couplet on the discrete storm to the southwest of the line.

SEVERE WEATHER STATEMENT

NATIONAL WEATHER SERVICE RAPID CITY SD

231 PM MDT THU AUG 11 2011

SDC033-047-103-113-112115-

/O.CON.KUNR.SV.W.0352.000000T0000Z-110811T2115Z/

SHANNON SD-PENNINGTON SD-CUSTER SD-FALL RIVER SD-

231 PM MDT THU AUG 11 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHEASTERN

FALL RIVER...EASTERN CUSTER...SOUTH CENTRAL PENNINGTON AND

NORTHWESTERN SHANNON COUNTIES UNTIL 315 PM MDT...

AT 228 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A

SEVERE THUNDERSTORM CAPABLE OF PRODUCING DANGEROUS AND EXTREMELY

LARGE DESTRUCTIVE HAIL UP TO SOFTBALL SIZE...AND DAMAGING WINDS IN

EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR RED SHIRT...OR 29

MILES NORTHEAST OF DOWNTOWN HOT SPRINGS...MOVING SOUTHEAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...

ROCKYFORD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN

DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY

LIKELY...IF A TORNADO IS SPOTTED ACT QUICKLY AND MOVE TO A PLACE OF

SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL

INTERIOR ROOM.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE

IMMEDIATELY FOR LARGE DESTRUCTIVE HAIL CAPABLE OF PRODUCING

SIGNIFICANT DAMAGE. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...

PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

Link to comment
Share on other sites

Edit: Nvm, here's the watch...

URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 767

NWS STORM PREDICTION CENTER NORMAN OK

435 PM CDT THU AUG 11 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

NORTHERN NEBRASKA

EFFECTIVE THIS THURSDAY AFTERNOON FROM 435 PM UNTIL MIDNIGHT CDT.

SEVERAL TORNADOES

SCATTERED DAMAGING WINDS

ISOLATED WIND GUSTS TO 70 MPH POSSIBLE

SCATTERED LARGE HAIL

ISOLATED HAIL TO 3.0 INCHES IN DIAMETER POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 35 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 80 MILES WEST NORTHWEST OF

MULLEN NEBRASKA TO 20 MILES EAST NORTHEAST OF ONEILL NEBRASKA.

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 766...

DISCUSSION...ISOLATED SUPERCELL THUNDERSTORMS ARE TRACKING

SOUTHEASTWARD ACROSS SD...AND WILL BEGIN AFFECTING PORTIONS OF THE

WATCH AREA IN THE NEXT 1-2 HOURS. MEANWHILE...INCREASING CU FIELD

MAY ALSO RESULT IN AN ISOLATED STORM OR TWO TO FORM OVER NORTHERN

NEB THIS EVENING. STRONG VERTICAL SHEAR AND AMPLE CAPE WILL SUPPORT

A RISK OF SUPERCELLS CAPABLE OF VERY LARGE HAIL AND DAMAGING WINDS.

STRENGTHENING LOW LEVEL WIND FIELDS DURING THE EVENING ALSO INDICATE

A RISK OF ISOLATED TORNADOES.

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

500. MEAN STORM MOTION VECTOR 30025.

...HART

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...