Although a few storms are ongoing, the threat increases over the next few days as the storm develops, and a Halloween tornado outbreak is possible. Setup seems reminiscent of November 15, 2005.
ZCZC SPCSWOD48 ALL
ACUS48 KWNS 280859
SPC AC 280859
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0359 AM CDT MON OCT 28 2013
VALID 311200Z - 051200Z
...DISCUSSION...
A SEVERE RISK REMAINS APPARENT ESPECIALLY ON DAY 4/THURSDAY. THIS
WILL BE AS A CONSIDERABLE UPPER TROUGH AND ASSOCIATED
EASTWARD-ACCELERATING COLD FRONT SPREAD EASTWARD AND INTERCEPT A
SEASONALLY MOIST LOW-LEVEL AIRMASS FROM THE ARKLATEX/LOWER MS RIVER
VALLEY INTO THE TN/OH RIVER VALLEYS. WHILE EARLY-DAY CONVECTION IS
AN UNCERTAINTY FACTOR...CURRENT THINKING IS THAT THE MOST FAVORABLE
/OR CERTAIN/ COMBINATION OF MODEST INSTABILITY/STRONG VERTICAL SHEAR
WILL BE ACROSS PORTIONS OF THE ARKLAMISS/TN VALLEY...ALTHOUGH
MID-LEVEL LAPSE RATES WILL BE WEAKER WITH SOUTHERN EXTENT. GIVEN A
VERY MOIST LOW-LEVEL AIRMASS AND AMPLE LOW-LEVEL/DEEP-LAYER
SHEAR...DAMAGING WINDS AND SOME TORNADOES /POTENTIALLY A FEW STRONG/
WILL BE POSSIBLE.
FARTHER NORTH ON DAY 4/THURSDAY...ALTHOUGH THE EXACT DEGREE OF
DESTABILIZATION IS UNCERTAIN...A SEVERE /DAMAGING WIND AND PERHAPS
TORNADO/ RISK CANNOT BE DISCOUNTED FOR ADDITIONAL PORTIONS OF THE OH
VALLEY/NEARBY GREAT LAKES. THIS INCLUDES THE POSSIBILITY OF A
STRONGLY FORCED/LOW-TOPPED CONVECTIVE LINE IN ASSOCIATION WITH
ROBUST VERTICAL SHEAR/FORCING FOR ASCENT.
INTO DAY 5/FRIDAY...THE STRONGEST UPPER TROUGH-ASSOCIATED ASCENT
SHOULD SPREAD AWAY FROM THE RICHEST LOW-LEVEL MOISTURE. EVEN SO...A
MOIST AIRMASS/VERY STRONG SHEAR COULD ACCOUNT FOR SOME STRONGER
STORMS ACROSS PARTS OF THE SOUTHEAST STATES AND PERHAPS ADDITIONAL
PARTS OF THE EASTERN CONUS.
..GUYER.. 10/28/2013
CLICK TO GET WUUS48 PTSD48 PRODUCT
Severe weather outbreak? October 29 - November 1
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brunota2003
- S2K Supporter
- Posts: 9476
- Age: 33
- Joined: Sat Jul 30, 2005 9:56 pm
- Location: Stanton, KY...formerly Havelock, NC
- Contact:
AFD from NWS Louisville, KY Monday afternoon...someone was definitely getting into the Halloween spirit!
Thursday...
Skies Thursday morning could appear ominous, with low and
upper-level clouds quickly moving to the northeast on strong winds
aloft. Could even see some rain and perhaps a few rumbles of thunder
nearby with some morning elevated instability before
dissipating/pushing northeast by late morning, as the main cold
frontal event ramps up to our west. Southerly winds will really
increase Thursday, howling out of the south. Temperatures will range
from the upper 60s in the northwest to lower 70s further south and
east.
Mysteriously dark clouds will approach from the west through the day
Thursday. The latest guidance shows the bulk of the precipitation
ahead of the front moving across the forecast area Thursday
afternoon and continuing through the evening hours. A good band of
widespread moderate to heavy showers and embedded thunderstorms
appear likely through the Ohio and Tennessee Valleys. Heavy rainfall
leading to localized flooding will be a primary concern as a
devilish ribbon of higher moisture is pulled northward along and
just ahead of the front, creating a precipitation efficient rainfall
potion. The other concern will be the possibility of some stronger
storms with this line. Forecast 0-6km bulk shear values of 30 to 70
knots during the afternoon and early evening and very little CAPE
are consistent within the guidance. This will be a high shear, low
CAPE cool season environment, which favors strong lower-topped
convection and a smaller thunder potential. Strong storms and
perhaps even severe are possible within this type of regime,
especially if these showers and storms can tap into a little more
surface-based instability. Any way you slice the situation, it is
definitely looking grim for outdoor plans Thursday evening.
Thursday...
Skies Thursday morning could appear ominous, with low and
upper-level clouds quickly moving to the northeast on strong winds
aloft. Could even see some rain and perhaps a few rumbles of thunder
nearby with some morning elevated instability before
dissipating/pushing northeast by late morning, as the main cold
frontal event ramps up to our west. Southerly winds will really
increase Thursday, howling out of the south. Temperatures will range
from the upper 60s in the northwest to lower 70s further south and
east.
Mysteriously dark clouds will approach from the west through the day
Thursday. The latest guidance shows the bulk of the precipitation
ahead of the front moving across the forecast area Thursday
afternoon and continuing through the evening hours. A good band of
widespread moderate to heavy showers and embedded thunderstorms
appear likely through the Ohio and Tennessee Valleys. Heavy rainfall
leading to localized flooding will be a primary concern as a
devilish ribbon of higher moisture is pulled northward along and
just ahead of the front, creating a precipitation efficient rainfall
potion. The other concern will be the possibility of some stronger
storms with this line. Forecast 0-6km bulk shear values of 30 to 70
knots during the afternoon and early evening and very little CAPE
are consistent within the guidance. This will be a high shear, low
CAPE cool season environment, which favors strong lower-topped
convection and a smaller thunder potential. Strong storms and
perhaps even severe are possible within this type of regime,
especially if these showers and storms can tap into a little more
surface-based instability. Any way you slice the situation, it is
definitely looking grim for outdoor plans Thursday evening.
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Just a small town southern boy helping other humans.
-
CrazyC83
- Professional-Met
- Posts: 33399
- Joined: Tue Mar 07, 2006 11:57 pm
- Location: Deep South, for the first time!
SPC AC 290730
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT TUE OCT 29 2013
VALID 311200Z - 011200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX/LOWER MS
RIVER VALLEY TO THE OH RIVER VALLEY...
...ARKLATEX/LOWER MS RIVER VALLEY TO THE TN/OH RIVER VALLEYS...
A LOW CAPE/HIGH SHEAR REGIME IS EXPECTED TO BRING AT LEAST AN
ISOLATED SEVERE RISK TO A BROAD REGIONAL EXTENT ON THURSDAY. A
CONSIDERABLE UPPER TROUGH OVER THE PLAINS EARLY THURSDAY SEEMS
LIKELY TO TAKE ON AN INCREASINGLY NEGATIVE TILT...ESPECIALLY BY
THURSDAY NIGHT AS IT CROSSES THE MIDWEST/OH RIVER VALLEY. VERY
STRONG SOUTH-SOUTHWESTERLY WINDS IN THE LOWEST FEW KM WILL QUICKLY
TRANSPORT A SEASONALLY MOIST AIRMASS NORTH-NORTHEASTWARD AHEAD OF A
COLD FRONT...WHICH WILL ACCELERATE EASTWARD ESPECIALLY THURSDAY
NIGHT ACROSS THE TN/OH RIVER VALLEYS AND MIDWEST. BY LATE
AFTERNOON/EARLY EVENING THURSDAY...LOWER 60S F SURFACE DEWPOINTS MAY
EXIST AS FAR NORTH AS PORTIONS OF IL/INDIANA AND OH.
WHILE EARLY CONVECTION AHEAD OF THE COLD FRONT WILL BE A
COMPLICATING FACTOR ACROSS PARTS OF THE ARKLATEX AND LOWER/MIDDLE MS
RIVER VALLEY...THE MOST FAVORABLE /OR CERTAIN/ COMBINATION OF MODEST
INSTABILITY/STRONG VERTICAL SHEAR THURSDAY AFTERNOON INTO EVENING
SHOULD MATERIALIZE GENERALLY ACROSS PORTIONS OF THE ARKLAMISS/TN
VALLEY...ALTHOUGH MID-LEVEL LAPSE RATES WILL BE WEAKER WITH
SOUTH-SOUTHWESTWARD EXTENT. GIVEN A VERY MOIST LOW-LEVEL AIRMASS AND
AMPLE LOW-LEVEL/DEEP-LAYER SHEAR...DAMAGING WINDS AND SOME TORNADOES
WILL BE POSSIBLE WITH WHAT SHOULD BE A COMPLEX STORM MODE INCLUDING
LINE-EMBEDDED BOWING STRUCTURES/SOME SEMI-DISCRETE SUPERCELLS. IN
FACT...A STRONG TORNADO RISK CANNOT BE DISCOUNTED ACROSS PARTS OF
THE LOWER MS VALLEY/TN VALLEY GIVEN THE ROBUST MAGNITUDE OF THE
LOW-LEVEL WINDS /50-65 KT IN LOWEST 1-2 KM/...VERY STRONG SRH...AND
THE MOIST BOUNDARY LAYER.
WHILE THE EXACT DEGREE OF DESTABILIZATION IS UNCERTAIN WITH
NORTHWARD EXTENT INTO THE OH RIVER VALLEY...LOW-LEVEL
MOISTURE/MEAGER INSTABILITY MAY BE SUFFICIENT FOR THE DEVELOPMENT OF
A FAST-MOVING/ACCELERATING LOW-TOPPED CONVECTIVE LINE THURSDAY
EVENING/OVERNIGHT ACROSS TN/OH RIVER VALLEYS. AS SUCH...IT APPEARS
THAT AT LEAST ISOLATED DAMAGING WIND GUSTS WILL NOCTURNALLY BE
POSSIBLE...EVEN IF THERE IS A RELATIVE ABSENCE OF
LIGHTNING-PRODUCING CONVECTION.
..GUYER.. 10/29/2013
CLICK TO GET WUUS03 PTSDY3 PRODUCT
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
CURRENT UTC TIME: 2059Z (4:59PM), RELOAD THIS PAGE TO UPDATE THE TIME
DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CDT TUE OCT 29 2013
VALID 311200Z - 011200Z
...THERE IS A SLGT RISK OF SVR TSTMS FROM THE ARKLATEX/LOWER MS
RIVER VALLEY TO THE OH RIVER VALLEY...
...ARKLATEX/LOWER MS RIVER VALLEY TO THE TN/OH RIVER VALLEYS...
A LOW CAPE/HIGH SHEAR REGIME IS EXPECTED TO BRING AT LEAST AN
ISOLATED SEVERE RISK TO A BROAD REGIONAL EXTENT ON THURSDAY. A
CONSIDERABLE UPPER TROUGH OVER THE PLAINS EARLY THURSDAY SEEMS
LIKELY TO TAKE ON AN INCREASINGLY NEGATIVE TILT...ESPECIALLY BY
THURSDAY NIGHT AS IT CROSSES THE MIDWEST/OH RIVER VALLEY. VERY
STRONG SOUTH-SOUTHWESTERLY WINDS IN THE LOWEST FEW KM WILL QUICKLY
TRANSPORT A SEASONALLY MOIST AIRMASS NORTH-NORTHEASTWARD AHEAD OF A
COLD FRONT...WHICH WILL ACCELERATE EASTWARD ESPECIALLY THURSDAY
NIGHT ACROSS THE TN/OH RIVER VALLEYS AND MIDWEST. BY LATE
AFTERNOON/EARLY EVENING THURSDAY...LOWER 60S F SURFACE DEWPOINTS MAY
EXIST AS FAR NORTH AS PORTIONS OF IL/INDIANA AND OH.
WHILE EARLY CONVECTION AHEAD OF THE COLD FRONT WILL BE A
COMPLICATING FACTOR ACROSS PARTS OF THE ARKLATEX AND LOWER/MIDDLE MS
RIVER VALLEY...THE MOST FAVORABLE /OR CERTAIN/ COMBINATION OF MODEST
INSTABILITY/STRONG VERTICAL SHEAR THURSDAY AFTERNOON INTO EVENING
SHOULD MATERIALIZE GENERALLY ACROSS PORTIONS OF THE ARKLAMISS/TN
VALLEY...ALTHOUGH MID-LEVEL LAPSE RATES WILL BE WEAKER WITH
SOUTH-SOUTHWESTWARD EXTENT. GIVEN A VERY MOIST LOW-LEVEL AIRMASS AND
AMPLE LOW-LEVEL/DEEP-LAYER SHEAR...DAMAGING WINDS AND SOME TORNADOES
WILL BE POSSIBLE WITH WHAT SHOULD BE A COMPLEX STORM MODE INCLUDING
LINE-EMBEDDED BOWING STRUCTURES/SOME SEMI-DISCRETE SUPERCELLS. IN
FACT...A STRONG TORNADO RISK CANNOT BE DISCOUNTED ACROSS PARTS OF
THE LOWER MS VALLEY/TN VALLEY GIVEN THE ROBUST MAGNITUDE OF THE
LOW-LEVEL WINDS /50-65 KT IN LOWEST 1-2 KM/...VERY STRONG SRH...AND
THE MOIST BOUNDARY LAYER.
WHILE THE EXACT DEGREE OF DESTABILIZATION IS UNCERTAIN WITH
NORTHWARD EXTENT INTO THE OH RIVER VALLEY...LOW-LEVEL
MOISTURE/MEAGER INSTABILITY MAY BE SUFFICIENT FOR THE DEVELOPMENT OF
A FAST-MOVING/ACCELERATING LOW-TOPPED CONVECTIVE LINE THURSDAY
EVENING/OVERNIGHT ACROSS TN/OH RIVER VALLEYS. AS SUCH...IT APPEARS
THAT AT LEAST ISOLATED DAMAGING WIND GUSTS WILL NOCTURNALLY BE
POSSIBLE...EVEN IF THERE IS A RELATIVE ABSENCE OF
LIGHTNING-PRODUCING CONVECTION.
..GUYER.. 10/29/2013
CLICK TO GET WUUS03 PTSDY3 PRODUCT
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z
CURRENT UTC TIME: 2059Z (4:59PM), RELOAD THIS PAGE TO UPDATE THE TIME
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WeatherGuesser
- Category 5
- Posts: 2672
- Joined: Tue Jun 29, 2010 6:46 am
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