Winter 2015-16

[John1122]

06Z GFS has a nice looking southern slider, nice HP in the western lakes and one in the eastern lakes/NE area, storm track through the central gulf coast states to NWFl and then off shore. 

 

Doesn't show it producing here on the run but as always, way too small a precip field with a low taking that track and not enough cold pressing down with a 1030+ high moving from northern Minnesota to just northwest of Chicago with lows in the -10s and highs in the single digits under the high in the upper mid-west. 

 

I'll take my chances if this set up were by some miracle to happen.

 

[jaxjagman]

I'm guessing that East Tennessee is in the grey?

Euro backed off last night,looks colder and dont see the winds.Looks like a bunch of cold rain in the Valley right now.Possibly the higher elev might see some snow

[John1122]

12z crept much closer to what we want to see from a cold/moisture/track point of view. Crushed North Carolina into oblivion that run. Precip shield finally made it into Tennessee but only gave us a couple of inches. Almost assuredly the system with have a bigger precip shield and be a bit NW of current track. Still a few days out but intriguing.

 

[John1122]

The 12z Canadian looks about like the 06z GFS. High in the lakes, low to our south. It's getting there too. This is the same timeframe as the big snow/ice/everything else event that capped off last winter.

[ShawnEastTN]

18Z GFS followed suit on low track but weakened the low keeping precip too far south.  Still good run though considering its the sweet spot for this time of the year to get northern edge snows, however 18z turned it into a OTS rather than hooking up the coast.  Still interesting to watch for possible early March snow.

[jaxjagman]

Chance of thunderstorms Tuesday and Thursday by the looks.If the NAM is right there would be a chance of some severe weather Tuesday somewhere in the Valley.Thursday looks blah with convection what the euro shows,shear isn't half bad though.We lack cold air for any  good snow by what the models are showing.Best chances still should be in the higher elev to see any snow.Still keeping an eye on some possible storms around the 12th.Climo we are creeping into our severe season in March-May

 

[jaxjagman]

Guess we'll see about Tuesday,GFS like the NAM is now showing some SBCapes around 600+ in the Western parts.So there is more instability being shown

[jaxjagman]

[jaxjagman]

OK. Now that we appear to have winter ending after the first week of March, it is time to concern ourselves with Spring. That is, warmer temperatures, chances for heavy rainfall and severe weather. My friends in the chaser community should understand, however, that this being an end-phase El Nino event suggests that the first half of the MAMJ period will present the greatest convective threats not in the famed "Tornado Alley". But rather in C, S TX and the Gulf States. Specifically, the corridor between Interstate 20 and 10 to the right of Interstate 35. If you can remember how 1998 progressed with respect to thunderstorm threats, that might be a useful analog.

I say that because there has been a very strong and well-defined subtropical jet stream. The southern branch wind field has been much farther south than normal (Mexico to Florida Peninsula), and will take its time with northward relocation and translation. Deriving a high yield of moisture from the equatorial Pacific Ocean, with the positive Pacific Decadal Oscillation helping to maintain a ridge axis along the West Coast, there will be a tendency for upper level lows/cold pools over the Southwest and "Four Corners" vicinity. Just such an occurrence is visible on all of the ensemble packages during the March 6 - 9 time frame.

This initial gyre will probably take a track, slowly, through C TX and then toward lower Appalachia. Remembering that the air mass east of the Rocky Mountains will be mild to warm, the precipitation that does take shape from Kansas to the Rio Grande will likely be all rain. The very gradual eastward translation bothers me, as it implies an excessive, long-duration rainfall event in cities such as Dallas TX, Houston TX, Shreveport LA, New Orleans LA and Jackson MS in the 11 - 15 day period. Severe weather concerns, mirroring the ideas posted above, will likely be from C, S TX and then along the length of the Gulf Coast. If the ECMWF ensemble package is correct, thunderstorm output will be memorable, or worse.

I think that the Spring season will be a big rain producer from the lower/middle Great Plains through most of the eastern half of the nation. Drought risks appear to be aimed at the northern High Plains/Upper Midwest. California may see some easement of groundwater deficiency over the next month or two, but by late May see a turn toward heat and dryness.

Prepared by Meteorologist LARRY COSGROVE

[Runman292]

What's the Euro showing for the 4th?

[jaxjagman]

What's the Euro showing for the 4th?

Euro has the system coming through the Valley and colder,but you'd like to see it further S,could see some wrap.GFS  looks basically dry

[jaxjagman]

DAY 3 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0229 AM CST SUN FEB 28 2016

   VALID 011200Z - 021200Z

   ...THERE IS A MRGL RISK OF SVR TSTMS TUESDAY AFTERNOON AND EVENING
   ACROSS PARTS OF SOUTHERN AND EASTERN TEXAS, THROUGH THE LOWER
   MISSISSIPPI VALLEY, AND PORTIONS OF THE OHIO/TENNESSEE VALLEYS...

   ...SUMMARY...
   STRONG STORMS...WITH SOME RISK FOR SEVERE WIND GUSTS AND HAIL...MAY
   IMPACT PARTS OF SOUTHERN AND EASTERN TEXAS INTO THE LOWER
   MISSISSIPPI VALLEY...AND PERHAPS PORTIONS OF THE LOWER OHIO AND
   TENNESSEE VALLEYS...TUESDAY AFTERNOON AND EVENING.

   ...SYNOPSIS...
   LITTLE CHANGE TO THE LARGE-SCALE UPPER PATTERN IS EXPECTED THROUGH
   THIS PERIOD.  RIDGING WITHIN A BELT OF MID-LATITUDE WESTERLIES
   APPEARS LIKELY TO PERSIST NEAR THE PACIFIC COAST...THOUGH IT MAY BE
   SUPPRESSED A BIT BY ANOTHER SHORT WAVE IMPULSE PROGRESSING INLAND
   AROUND ITS CREST...ACROSS THE PACIFIC NORTHWEST. 

   WHILE A SIGNIFICANT PRECEDING IMPULSE PROGRESSES EAST/SOUTH OF THE
   CENTRAL U.S. PLAINS...THERE MAY BE SOME ELONGATION OF THE EASTERN
   CANADIAN VORTEX IN RESPONSE TO SHORT WAVES PIVOTING AROUND ITS
   CIRCULATION CENTER.  THIS INCLUDES ONE VIGOROUS IMPULSE FORECAST TO
   DIG TO THE SOUTHWEST OF HUDSON BAY...TOWARD THE UPPER GREAT LAKES
   REGION.  THIS LATTER FEATURE LIKELY WILL BE ACCOMPANIED BY ANOTHER
   MORE SUBSTANTIVE SURGE OF SEASONABLY COLD AIR INTO THE NORTHERN
   PLAINS AND UPPER MIDWEST BY LATE TUESDAY NIGHT...AS A PRECEDING COLD
   INTRUSION ADVANCES INTO THE VICINITY OF THE APPALACHIANS...AND
   THROUGH THE LOWER MISSISSIPPI VALLEY/WESTERN GULF COAST REGION.

   THE POTENTIAL INTERACTION BETWEEN THE IMPULSE INITIALLY OVER THE
   PLAINS AND THE ONE APPROACHING THE UPPER GREAT LAKES REGION...AND
   THEIR SUBSEQUENT EVOLUTION...REMAIN ONE POINT OF CONSIDERABLE
   VARIABILITY AMONG THE MODELS.  ANOTHER CONCERNS THE STRENGTH AND
   TIMING OF THE INITIAL COLD INTRUSION RELATIVE TO THE ARRIVAL OF THE
   PLAINS IMPULSE...AND ITS IMPACT ON FRONTAL WAVE DEVELOPMENT ACROSS
   THE MIDDLE MISSISSIPPI VALLEY THROUGH PARTS OF THE UPPER OHIO VALLEY
   AND NORTHERN MID ATLANTIC COAST STATES. 

   IT CURRENTLY SEEMS MOST PROBABLE THAT SURFACE CYCLOGENESIS WILL
   REMAIN SUBDUED THROUGH THIS PERIOD.  HOWEVER...STRENGTHENING OF WIND
   FIELDS AND LOW-LEVEL MOISTENING WITHIN AN EXPANDING WARM SECTOR
   COULD CONTRIBUTE TO AN ENVIRONMENT AT LEAST MARGINALLY SUPPORTIVE OF
   SEVERE STORM DEVELOPMENT...FROM PARTS OF SOUTHERN AND EASTERN TEXAS
   INTO THE LOWER OHIO AND TENNESSEE VALLEYS.
    
   ...SRN/ERN TX THROUGH THE LWR MS/OH AND TN VALLEYS...
   MODELS ARE CURRENTLY SUGGESTIVE THAT STRENGTHENING WIND FIELDS
   ASSOCIATED WITH THE DEVELOPING SURFACE WAVE WILL TEND TO SHIFT FROM
   THE SOUTH CENTRAL PLAINS/OZARK PLATEAU EAST NORTHEASTWARD THROUGH
   THE OHIO/TENNESSEE VALLEY REGION TUESDAY INTO TUESDAY NIGHT.
   SURFACE DEW POINTS INLAND OF THE GULF COAST MAY ONLY REACH THE UPPER
   50S TO LOW 60S...BUT THIS MAY BE SUFFICIENT TO CONTRIBUTE TO MODEST
   CAPE...AT LEAST BENEATH THE RELATIVELY STEEP MID-LEVEL LAPSE RATES.
   THE EVOLVING PATTERN MAY RESULT IN THE STEEPER MID-LEVEL LAPSE RATES
   BECOMING CONFINED TO THE ARKLATEX SOUTHWESTWARD INTO THE LOWER RIO
   GRANDE VALLEY...WHERE WIND FIELDS WILL BE WEAKER.  BUT LOW-LEVEL
   MOISTENING COULD STILL CONTRIBUTE TO WEAK DESTABILIZATION WITHIN A
   PLUME NEAR THE TRACK OF THE LOW.

   AIDED BY FORCING FOR LARGE-SCALE ASCENT AHEAD OF THE IMPULSE
   PROGRESSING EAST SOUTHEAST OF THE PLAINS...THE INITIATION OF
   SCATTERED VIGOROUS THUNDERSTORM ACTIVITY APPEARS POSSIBLE TUESDAY
   AFTERNOON AHEAD OF THE COLD FRONT.  THIS MAY BE INITIALLY FOCUSED
   ALONG A NARROW PRE-FRONTAL LOW-LEVEL THERMAL RIDGE...ACROSS
   SOUTHERN/EASTERN TEXAS...EAST NORTHEASTWARD TOWARD THE
   OHIO/TENNESSEE VALLEYS.  ACTIVITY IS EXPECTED TO EVENTUALLY BECOME
   UNDERCUT BY THE COLD FRONT.  BEFORE IT DOES...THOUGH...STRONGER
   CONVECTION COULD BE ACCOMPANIED BY MARGINALLY SEVERE WIND AND HAIL.

[Runman292]

DAY 3 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

0229 AM CST SUN FEB 28 2016

VALID 011200Z - 021200Z

...THERE IS A MRGL RISK OF SVR TSTMS TUESDAY AFTERNOON AND EVENING

ACROSS PARTS OF SOUTHERN AND EASTERN TEXAS, THROUGH THE LOWER

MISSISSIPPI VALLEY, AND PORTIONS OF THE OHIO/TENNESSEE VALLEYS...

...SUMMARY...

STRONG STORMS...WITH SOME RISK FOR SEVERE WIND GUSTS AND HAIL...MAY

IMPACT PARTS OF SOUTHERN AND EASTERN TEXAS INTO THE LOWER

MISSISSIPPI VALLEY...AND PERHAPS PORTIONS OF THE LOWER OHIO AND

TENNESSEE VALLEYS...TUESDAY AFTERNOON AND EVENING.

...SYNOPSIS...

LITTLE CHANGE TO THE LARGE-SCALE UPPER PATTERN IS EXPECTED THROUGH

THIS PERIOD. RIDGING WITHIN A BELT OF MID-LATITUDE WESTERLIES

APPEARS LIKELY TO PERSIST NEAR THE PACIFIC COAST...THOUGH IT MAY BE

SUPPRESSED A BIT BY ANOTHER SHORT WAVE IMPULSE PROGRESSING INLAND

AROUND ITS CREST...ACROSS THE PACIFIC NORTHWEST.

WHILE A SIGNIFICANT PRECEDING IMPULSE PROGRESSES EAST/SOUTH OF THE

CENTRAL U.S. PLAINS...THERE MAY BE SOME ELONGATION OF THE EASTERN

CANADIAN VORTEX IN RESPONSE TO SHORT WAVES PIVOTING AROUND ITS

CIRCULATION CENTER. THIS INCLUDES ONE VIGOROUS IMPULSE FORECAST TO

DIG TO THE SOUTHWEST OF HUDSON BAY...TOWARD THE UPPER GREAT LAKES

REGION. THIS LATTER FEATURE LIKELY WILL BE ACCOMPANIED BY ANOTHER

MORE SUBSTANTIVE SURGE OF SEASONABLY COLD AIR INTO THE NORTHERN

PLAINS AND UPPER MIDWEST BY LATE TUESDAY NIGHT...AS A PRECEDING COLD

INTRUSION ADVANCES INTO THE VICINITY OF THE APPALACHIANS...AND

THROUGH THE LOWER MISSISSIPPI VALLEY/WESTERN GULF COAST REGION.

THE POTENTIAL INTERACTION BETWEEN THE IMPULSE INITIALLY OVER THE

PLAINS AND THE ONE APPROACHING THE UPPER GREAT LAKES REGION...AND

THEIR SUBSEQUENT EVOLUTION...REMAIN ONE POINT OF CONSIDERABLE

VARIABILITY AMONG THE MODELS. ANOTHER CONCERNS THE STRENGTH AND

TIMING OF THE INITIAL COLD INTRUSION RELATIVE TO THE ARRIVAL OF THE

PLAINS IMPULSE...AND ITS IMPACT ON FRONTAL WAVE DEVELOPMENT ACROSS

THE MIDDLE MISSISSIPPI VALLEY THROUGH PARTS OF THE UPPER OHIO VALLEY

AND NORTHERN MID ATLANTIC COAST STATES.

IT CURRENTLY SEEMS MOST PROBABLE THAT SURFACE CYCLOGENESIS WILL

REMAIN SUBDUED THROUGH THIS PERIOD. HOWEVER...STRENGTHENING OF WIND

FIELDS AND LOW-LEVEL MOISTENING WITHIN AN EXPANDING WARM SECTOR

COULD CONTRIBUTE TO AN ENVIRONMENT AT LEAST MARGINALLY SUPPORTIVE OF

SEVERE STORM DEVELOPMENT...FROM PARTS OF SOUTHERN AND EASTERN TEXAS

INTO THE LOWER OHIO AND TENNESSEE VALLEYS.

...SRN/ERN TX THROUGH THE LWR MS/OH AND TN VALLEYS...

MODELS ARE CURRENTLY SUGGESTIVE THAT STRENGTHENING WIND FIELDS

ASSOCIATED WITH THE DEVELOPING SURFACE WAVE WILL TEND TO SHIFT FROM

THE SOUTH CENTRAL PLAINS/OZARK PLATEAU EAST NORTHEASTWARD THROUGH

THE OHIO/TENNESSEE VALLEY REGION TUESDAY INTO TUESDAY NIGHT.

SURFACE DEW POINTS INLAND OF THE GULF COAST MAY ONLY REACH THE UPPER

50S TO LOW 60S...BUT THIS MAY BE SUFFICIENT TO CONTRIBUTE TO MODEST

CAPE...AT LEAST BENEATH THE RELATIVELY STEEP MID-LEVEL LAPSE RATES.

THE EVOLVING PATTERN MAY RESULT IN THE STEEPER MID-LEVEL LAPSE RATES

BECOMING CONFINED TO THE ARKLATEX SOUTHWESTWARD INTO THE LOWER RIO

GRANDE VALLEY...WHERE WIND FIELDS WILL BE WEAKER. BUT LOW-LEVEL

MOISTENING COULD STILL CONTRIBUTE TO WEAK DESTABILIZATION WITHIN A

PLUME NEAR THE TRACK OF THE LOW.

AIDED BY FORCING FOR LARGE-SCALE ASCENT AHEAD OF THE IMPULSE

PROGRESSING EAST SOUTHEAST OF THE PLAINS...THE INITIATION OF

SCATTERED VIGOROUS THUNDERSTORM ACTIVITY APPEARS POSSIBLE TUESDAY

AFTERNOON AHEAD OF THE COLD FRONT. THIS MAY BE INITIALLY FOCUSED

ALONG A NARROW PRE-FRONTAL LOW-LEVEL THERMAL RIDGE...ACROSS

SOUTHERN/EASTERN TEXAS...EAST NORTHEASTWARD TOWARD THE

OHIO/TENNESSEE VALLEYS. ACTIVITY IS EXPECTED TO EVENTUALLY BECOME

UNDERCUT BY THE COLD FRONT. BEFORE IT DOES...THOUGH...STRONGER

CONVECTION COULD BE ACCOMPANIED BY MARGINALLY SEVERE WIND AND HAIL.

Lol, Knox County is outside of the marginal risk. That's definitely not surprising.

[Carvers Gap]

12z Euro, John. What ya got? Also, how close was the rock slide on 75 to you?

[John1122]

12z Euro was south of it's 00z track that went right across Tennessee and was a Miller A track from Dallas to Central Georgia to off Myrtle. Doesn't have a ton of precip with it this far north for whatever reason. The 540 is along I-40 as are the 850s. The 2m freezing line is around the Kentucky border. North Carolina took a pretty good hit in the East Central areas. I'd take my chances with that track and count on the precip shield being more healthy.

 

The rockslide is a few miles from me and making life miserable here.

[John1122]

12z JMA is a miller A track. EPS now south of Tennessee with the track. GFS says nothing to see here, storm is dying out.  Canadian goes across Kentucky with a B track, reforms off SW NC.

[Carvers Gap]

12z JMA is a miller A track. EPS now south of Tennessee with the track. GFS says nothing to see here, storm is dying out. Canadian goes across Kentucky with a B track, reforms off SW NC.

Yep. Just keeping an eye on it now, but it's continued the trend south with it. Even left some wiggle room for the northwest jog. Really was a slider on the EPS. I have a feeling this turns the corner...might be to Columbus, but have to like that track for now.

[jaxjagman]

The system Tuesday is colder again looks like an inch I-40 N

Sent from my VS986 using Tapatalk

[John1122]

GFS run was weird, took the low deep into the Gulf and appears to transfer from the central Gulf to off Florida's east coast.

 

We have precip, there's a huge gap between us and the lower gulf states with nothing.

 

Has cold 850s, 540 south of us, but the surface is in the low to mid 40s so it's light rain as the High in the upper midwest disappears and one pops up way East of the apps.

 

All around odd run and one I can't see verifying.

[jaxjagman]

OHX disco this afternoon is showing the euro as the outlier.They don't believe the cold front will get in as fast as the euro has been showing it would,This would kill any snow hopes the first of the week and the 2nd system afterwards i assume would bring in a better warm nose as they say it's just going to rain in our area being the models show  the system is south of us in the Valley

[Daniel Boone]

OHX disco this afternoon is showing the euro as the outlier.They don't believe the cold front will get in as fast as the euro has been showing it would,This would kill any snow hopes the first of the week and the 2nd system afterwards i assume would bring in a better warm nose as they say it's just going to rain in our area being the models show  the system is south of us in the Valley

Which model are they buying into then ?, the usual gfs ?

[Daniel Boone]

Not saying Gfs will be wrong as it does occasionally score a coup , as it did recently.

[jaxjagman]

Which model are they buying into then ?, the usual gfs ?

Not sure,but looking at the models this afternoon the NAM is more right to me.I'm just comparing the 18Z run for thermals off the latest runs and the actual OBS being shown.Just looking at our area we are at 62 right now the GFS already shows the cold front gone by we should be around 52.The NAM shows different and has us at 61 which is more correct

[jaxjagman]

The cold front is from Clarksville to Jackson in that area,even the WPC is wrong to me

 

Edit:wrong about the WPC,the cold front is still north,not sure about the GFS ON ITS THERMALS,WAY TO COLD

[jaxjagman]

Cold front is still well north

 

[nrgjeff]

Looks like Wednesday ends as snow Plateau and Mountains, perhaps East Kentucky and all of southwest Virginia. Otherwise it is cold chasing rain, or perhaps cold chasing severe!

 

Euro and its Parallel have consistently shown the end of week low tracking south. GFS is all over the place. I cannot imagine why anyone would use it, esp with the remarkably consistent Euro and Para. While I believe the boundary layer will be too warm for Valley snow I am very interested in this system for mountain snow. With enough cooling eastern Kentucky and southwest Virginia could also see snow. Otherwise lack of surface high, or one retreating quickly, spells warm surface at lower elevations. Mountains could see a nice system though, and the Upper Plateau could surprise. Euro has a good track and we know the (higher elevation only) snow shield will be heavier farther north than shown.

[Carvers Gap]

Looks like Wednesday ends as snow Plateau and Mountains, perhaps East Kentucky and all of southwest Virginia. Otherwise it is cold chasing rain, or perhaps cold chasing severe!

Euro and its Parallel have consistently shown the end of week low tracking south. GFS is all over the place. I cannot imagine why anyone would use it, esp with the remarkably consistent Euro and Para. While I believe the boundary layer will be too warm for Valley snow I am very interested in this system for mountain snow. With enough cooling eastern Kentucky and southwest Virginia could also see snow. Otherwise lack of surface high, or one retreating quickly, spells warm surface at lower elevations. Mountains could see a nice system though, and the Upper Plateau could surprise. Euro has a good track and we know the (higher elevation only) snow shield will be heavier farther north than shown.

Glad you are seeing that as well. All of the 12z ops hinted at this. And yeah, the GFS has looked rough w this for multiple runs. The 12z CMC moved towards the Euro track. The 12z Euro was similar to 0z and even had some accumulations over the Plateau, northern Valley, and spine of the Apps. 2-3" for TRI. 5-6" in mtns. 2-3" over the Plateau. I hold out hopes for NE TN to see some snow from this. But places like Max Patch, Smokies, Roan...look like a decent shot if the system can indeed actually stay south...

[Runman292]

Glad you are seeing that as well. All of the 12z ops hinted at this. And yeah, the GFS has looked rough w this for multiple runs. The 12z CMC moved towards the Euro track. The 12z Euro was similar to 0z and even had some accumulations over the Plateau, northern Valley, and spine of the Apps. 2-3" for TRI. 5-6" in mtns. 2-3" over the Plateau. I hold out hopes for NE TN to see some snow from this. But places like Max Patch, Smokies, Roan...look like a decent shot if the system can indeed actually stay south...

Is it safe to assume that winter is over for the Central and Southern Valley?

[Stovepipe]

Is it safe to assume that winter is over for the Central and Southern Valley?

 

Yes.

[Carvers Gap]

Is it safe to assume that winter is over for the Central and Southern Valley?

Would not rule anything out w this Nino, especially big mtn snows. But hey, the window for winter is closing fast for all of us. I have to admit that the sunshine and warm temps have been a welcome sight.