12/20-12/21 Moderate/Intense Clipper Event?

[Chicago Storm]

Sad part is, he is right. Look at that MW storm last week. Disgusting mess where models were concerned. Euro shows a monster 1888 style for the EC, while the GFS said NO and then next day the Euro takes it OTS. 0z American models all show a big hit for central Ohio tonight,the sref was showing a big hit earlier, and now they are flopping around like a Male nudist on a seesaw. It's sad really. I feel bad for mets. I wanted to be one, but I dont know if I could deal with the critisizm you guys must take when models are acting stupid.

Thanks for the mental picture.

[prinsburg_wx]

06Z NAM further n yet at 72...has a L in ne SD

[JayPSU]

06Z NAM further n yet at 72...has a L in ne SD

With another down in OK.

[prinsburg_wx]

MPX AFD

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN

200 AM CST SAT DEC 18 2010

LATEST MODEL TRENDS FOR MONDAY/MONDAY NIGHTS WX SYSTEM IS INDICATING

ANOTHER POTENTIAL SNOW STORM FOR S MN. THERE REMAINS SOME

UNCERTAINTY IN TERMS OF MID LEVEL FEATURES AND TIMING AS MODELS

HAVE BEEN TRENDING A BIT SLOWER...THE OVERALL PICTURE HAS OUR AREA

UNDER THE GUN OF WINTER STORM CRITERIA.

AS WITH PREVIOUS SNOW STORMS THAT HAVE AFFECTED OUR REGION...THE

PATH OF THE 70H LOW AND MAXIMIZED AREA OF CONVERGENCE/OMEGA OF THE

-12 TO -18C /DENDRITIC ZONE/ ARE SOMEWHAT SIMILAR TO MONDAYS

STORM. A BLEND OF THE NAM/GFS QPF AMTS OF BOTH THE MEAN/MODE

GENERATES NEARLY A HALF INCH OF LIQUID WATER BY TUESDAY MORNING.

DEPENDING UPON THE AMOUNT OF ARCTIC AIR IN PLACE AS THE SYSTEM

NEARS...WILL RESULT IN SNOWFALL RATIOS WHICH COULD BE HIGH ON THE

NORTHERN EDGE OF THIS STORM SYSTEM. WITH QPF AMTS NEAR 0.50 AND

WITH A CONSERVATIVE 15-1 SNOWFALL RATIO...WOULD YIELD AROUND 8

INCHES OF SNOW. ANY DEVIATION TO THESE FACTORS /QPF OR SNOWFALL

RATIOS/ WOULD RESULT IN HIGHER OR LOWER SNOWFALL AMTS. TOO EARLY

TO ISSUE A WINTER STORM WATCH...BUT SATURDAY DAY SHIFT MAY NEED

TO...OR DURING THE EVENING DEPENDING UPON THE LATEST MODEL TRENDS.

IF THIS IS NOT ENOUGH...ANOTHER STORM MAY AFFECT THE REGION BY

CHRISTMAS EVE WHICH ANOTHER FEW INCHES OF SNOW MAY FALL. WILL

HIGHLIGHT THE MORNING HWO ON THESE TWO SYSTEMS...AND THE AFFECTS

OF TRAVEL AND HOLIDAY SHOPPING. ..JLT..

[cromartie]

MKE mentions the storm will ingest enough warm air to produce rain in southern WI. Seems to be the status quo this year.... Rain/35F with SE winds belching off lake Michigan, then backside crust, then down into the deep freeze for a few days. LOL.

[Stebo]

MKE mentions the storm will ingest enough warm air to produce rain in southern WI. Seems to be the status quo this year.... Rain/35F with SE winds belching off lake Michigan, then backside crust, then down into the deep freeze for a few days. LOL.

Just so everyone knows what you are suggesting, and what MKE actually said

GFS/ECMWF BOTH NOW BRING A SWATH OF UPWARD VERTICAL MOTION AND

SUBSEQUENT QPF ACROSS THE WESTERN PORTIONS OF THE AREA MONDAY...THEN

ACROSS THE ENTIRE AREA MONDAY NIGHT...WITH THE ECMWF LINGERING INTO

TUESDAY NIGHT. ISENTROPIC LIFT GRADUALLY INCREASES ACROSS THE AREA

MONDAY INTO MONDAY NIGHT. 600MB FRONTOGENESIS RESPONSE SHIFTS ACROSS

PORTIONS OF THE AREA MONDAY NIGHT...HELPING TAP DENDRITE SNOW

CRYSTAL GROWTH ZONE. THIS SHOULD LEAD TO A BAND OF MODERATE SNOW

SHIFTING THROUGH THE AREA MONDAY NIGHT. KEPT CHANCE POPS

MONDAY...THEN WENT LIKELY FOR MONDAY NIGHT. IF WARMER ECWMF

VERIFIES...COULD SEE A MIX OF PRECIPITATION...AS 540DKM LINE SHIFTS

INTO THE SOUTHWEST AND FAR SOUTHERN PORTIONS OF THE AREA.

Note they say If the ecmwf verifies, and they mention SW and Southern portions of CWA, not entire area, nor along the water. Just posting this to help spin things correctly

[Thundersnow12]

[TimChgo9]

I will wait until this thing gets on shore and sampled better. With the way the last storm performed, I am not putting a whole lot of faith in any one model solution at the moment.

From the available QPF, which, if I don't miss my guess has been fairly consistent staying in the range of .25 to .50 for NE IL, SE WI, NW IN. Depending on ratios that could be a decent 3" - 6" even for around here, of course we will have to see where this storm tracks, and it's actual strength. I am not placing any bets anywhere for the moment.

[goknights]

My bet is hpc busts south

[Thundersnow12]

LOT

SECOND AND A BIT STRONGER WAVE MOVES ACROSS THE AREA LATE MONDAY

AFTERNOON INTO MONDAY NIGHT. TEMPERATURES LIKELY TO REACH THE

UPPER 20S TO LOWER 30S MONDAY AND INCREASING CLOUDS AHEAD OF THIS

NEXT SYSTEM SHOULD HOLD TEMPS STEADY IN THE MID/UPPER 20S MONDAY

NIGHT. SOUNDINGS/THERMAL PROFILES SHOW PRECIP TYPE REMAINING ALL

SNOW MONDAY NIGHT BUT AS MID/HIGH CLOUDS DEPART TUESDAY...COULD

SEE SOME DRIZZLE AS TEMPS CLIMB INTO THE LOW/MID 30S.

IN GENERAL...MODELS IN FAIR AGREEMENT WITH STORM TOTAL QPF IN THE

0.4 TO 0.5 INCH RANGE. HOWEVER...THE LOCATION OF THIS BAND OF

HEAVIER QPF CONTINUES TO SHIFT AND IN THE LATEST RUNS HAS SHIFTED

A BIT FURTHER NORTH. AND WITH WARMER SFC TEMPS IN THE MID/UPPER

20S MONDAY NIGHT...SNOW/WATER RATIOS LIKELY TO BE IN THE 10 TO 1

RANGE...PERHAPS STARTING A BIT DRIER AND ENDING A BIT WETTER. SO

ITS POSSIBLE SEVERAL INCHES OF SNOW COULD FALL MONDAY NIGHT BUT

LOCATION OF WHERE THE HEAVIEST SNOW SETS UP IS TOO UNCERTAIN AT

THIS POINT.

DVN

THE NEXT...MUCH STRONGER SYSTEM MOVES TOWARDS THE AREA MONDAY AND

MONDAY NIGHT...WITH FAR MORE VARIANCE IN HOW THE MODELS HANDLE IT.

THE GFS IS FASTER AND HAS A SINGLE SURFACE LOW THAT TRACKS FROM

EASTERN COLORADO SOUTHEAST TO OKLAHOMA...AND A SECOND THAT FORMS IN

NORTHERN MISSOURI AND TRACKS EAST INTO ILLINOIS AND INDIANA. THERE

IS ALSO A TRAILING UPPER LEVEL SHORTWAVE THAT HELPS FORM A FAIRLY

STRONG INVERTED TROUGH WHICH MOVES ACROSS IOWA AND ILLINOIS. THE

ECMWF HAS A MUCH STRONGER FORM OF THIS FEATURE...AND THE SOUTHERN

FEATURE IS WEAKER...SO IT PRODUCES MORE IN THE WAY OF SNOW...AND

TRACKS A SURFACE LOW ACROSS MINNESOTA TUESDAY. IT IS ALSO MUCH

SLOWER THAN THE GFS. FOR NOW HAVE TRIED TO PLAY A MIDDLE OF THE

ROAD PLAN...AS EITHER SOLUTION PRODUCES A DECENT 3 TO 6 INCH SNOW

FOR THE AREA...WITH THE MAIN QUESTION BEING THE TRACK OF THE

HEAVIEST SNOW BAND AND ANY MIXED PRECIPITATION TYPES ACROSS THE

SOUTH.

DMX

THE MAIN STORM SYSTEM IS SET TO MOVE ACROSS NORTHERN IOWA ON

MONDAY. LATEST WV IMAGERY SHOWS A SHORTWAVE ON THE WESTERN SIDE OF

AN OCCLUDED CYCLONE LOCATED JUST OFF THE BRITISH COLUMBIA COAST.

H500 SHOWS VERY COLD AIR WITHIN THIS CYCLONE...AS CORE TEMPS ARE

NEAR -40. THIS SHORTWAVE WILL ROTATE AROUND THE PARENT CYCLONE...AND

NUMERICAL MODELS DEPICT IT MOVING ACROSS THE ROCKIES AND EMERGING

OVER THE HIGH PLAINS ON SUNDAY NIGHT. THIS WILL SET UP AN AREA OF QG

FORCING OVER THE UPPER MIDWEST ON MONDAY...WITH A FRONTOGENETICALLY

FORCED BAND OF SNOW EXPECTED TO DEVELOP AND MOVE ACROSS NORTHERN

IOWA/SOUTHERN MN.. GFS 18.00 IS FURTHER SOUTH THAN THE ECMWF OR NAM.

THE GFS HAS THE BAND OF MODERATE SNOWFALL OVER THE IA/MN

BORDER...WHILE THE NAM KEEPS THE PRECIP OVER SOUTHERN

MINNESOTA...AND THE ECMWF IS MORE TOWARD CENTRAL MN. THERE ISNT

ABUNDANT MOISTURE FOR THIS SYSTEM TO WORK WITH...BUT CROSS SECTIONS

SHOW OMEGA CENTERED IN THE DENDRITIC GROWTH ZONE...SO EXPECT AT

LEAST PERIODS OF MODERATE SNOWFALL BEGINNING MONDAY MORNING IN THE

NORTHWEST...AND SPREADING EAST/SOUTHEASTWARD THROUGHOUT THE DAY. GFS

COBB OUTPUT HAS BEEN CONSISTENT WITH 4+ INCHES OF ACCUMULATION IN

THE NORTHERN CWA WHICH IS CONSISTENT WITH LATEST WWD SO HEADLINES

MAY BE NEEDED AS WE GET CLOSER TO THIS EVENT. CURRENT THINKING IS

THAT TOTAL ACCUMULATIONS WOULD BE MORE IN THE ADVISORY BALLPARK.

[Thundersnow12]

My bet is hpc busts south

Lets hear why

[Stebo]

My bet is hpc busts south

That would be my bet right now if i were wagering.

[TimChgo9]

Busts south for who?

[Stebo]

Busts south for who?

I'd say the brunt of the snows won't be across Northern Iowa like they are showing. More so over Southern Minnesota.

[buckeye]

just saw the euro...and the gfs...

not too often you see them at twins at 168hrs...same placement and strength of low over ky xmas eve.

[TimChgo9]

I am nervous about the fact that LOT seems to think this could mix a little bit. Not too wild about that thought.

[roardog]

just saw the euro...and the gfs...

not too often you see them at twins at 168hrs...same placement and strength of low over ky xmas eve.

Oh, so what you're saying is snowstorm for Green Bay.

[Thundersnow12]

I am nervous about the fact that LOT seems to think this could mix a little bit. Not too wild about that thought.

Its still too early to get caught up or worried about precip type.

[goknights]

Vort max on nam is across central minn

[goknights]

Basically every model is trending north that's my thinking

[TimChgo9]

just saw the euro...and the gfs...

not too often you see them at twins at 168hrs...same placement and strength of low over ky xmas eve.

That means you can put that low over Chicago on Christmas Eve , and "mix it up".... FOFL..... Over KY @ 168 hrs? Yeah, move that sucker north by the end of the week....

[snowstormcanuck]

The H5 placement at 84 on the NAM is so far north, I'd normally assume I'm heading for a SN>RA transition storm. But because of that turd spinning south of Nova Scotia, it's still going to be suppressed south of me. Good grief.

[Harry]

With this i have strong doubts about the NAM etc..

Hopefully by 12z tomorrow we should have a better idea as that energy to the wsw/sw of the main system in the Pacific should be rolling into the coast.

[goknights]

Harry what are your doubts?

[cyclone77]

Well, the NAM still says the Bears/Vikings game Monday night will be snowy. Maybe if there's some snow accumulation on the field it will give them better traction, as it sounds like the field will be very icy and hard the way it is now.

[Harry]

Harry what are your doubts?

That the storm is as disorganized ( with one piece of energy in the far north and another way south ) as the NAM shows.

This is a better look at everything.

[buckeye]

That means you can put that low over Chicago on Christmas Eve , and "mix it up".... FOFL..... Over KY @ 168 hrs? Yeah, move that sucker north by the end of the week....

[sarcasm] you're right, come to think of it, that canadian vortex has been a real underachiever this season so far [sarcasm/]

seriously, this year we've missed both clipper events to the southwest....why would these be any different

[Harry]

[sarcasm] you're right, come to think of it, that canadian vortex has been a real underachiever this season so far [sarcasm/]

seriously, this year we've missed both clipper events to the southwest....why would these be any different

Because that block is starting to shift some. Once it does get out of the way we go back to the typical worrying over systems tracking to the nw ( aka some se ridging ) vs what we have. For how long that lasts ( worrying over too far nw ) depends on who you ask.

[snowstormcanuck]

Because that block is starting to shift some. Once it does get out of the way we go back to the typical worrying over systems tracking to the nw ( aka some se ridging ) vs what we have. For how long that lasts ( worrying over too far nw ) depends on who you ask.

Are we talking about the Xmas storm here? Because for the first clipper the block has shifted west due to the rapid deepening of that Atlantic cyclone. In fact, that's why the NAM is showing that strung out piece of garbage. As it takes a further north track initially, it has to shear out quicker once it runs into that area of confluence over the Eastern Lakes/NNE.

[TugHillMatt]

Because that block is starting to shift some. Once it does get out of the way we go back to the typical worrying over systems tracking to the nw ( aka some se ridging ) vs what we have. For how long that lasts ( worrying over too far nw ) depends on who you ask.

What are your thoughts for us here in SW Mich. on Mon/Tues.? I think it's looking pretty good for us. Unfortunately this winter has had everything going northwest or southwest of us...so I'm a bit hesitant to bite.

By the way, snowing pretty good here now with the Lake effect/enhanced precip. Looking forward to getting a couple inches.