328 replies to this topic

[michsnowfreak]

With the arctic surge this weekend all but a certainty, figured a thread was due. Plummeting temps are a given, the wild card is snowfall accumulations. Most should see at least a dusting but some might see a nice blanket of snow. Its up in the air who will see the best snow though. Also cant rule out convection.

[michsnowfreak]

Once this gets into High-Res territory, Im wondering if there will be a brief but heavy band of snow with the front? The GEM seems to be hinting at that.

[SpartyOn]

Thinking a pencil thin squall line with a brief pick up in the winds. Might get a few good LES showers setting up shop in the typical locales 96-94 corrs.

To add.

The 0z NAM remains the most bullish with this feature while it pushes into NE OH. It really blows up into something nice.

[OHweather]

michsnowfreak, on 8 February 2012 - 11:47 PM, said:

Once this gets into High-Res territory, Im wondering if there will be a brief but heavy band of snow with the front? The GEM seems to be hinting at that.

It certainly seems possible with surface temps pushing well into the 30s ahead of the front. Mid level temps look boarderline for convection along the front with surface to 850mb delta t's of around 10C. Moisture off the lakes may enhance any precip along the front as well. Maybe a quick half inch to an inch for a lot of people as the front comes through?

[michsnowfreak]

SpartyOn, on 8 February 2012 - 11:52 PM, said:

Thinking a pencil thin squall line with a brief pick up in the winds. Might get a few good LES showers setting up shop in the typical locales 96-94 corrs.

To add.

The 0z NAM remains the most bullish with this feature while it pushes into NE OH. It really blows up into something nice.

Will you be on the road to MD?

[Geos]

The WRF NMM clearly shows squalls with the Arctic boundary.

[SpartyOn]

michsnowfreak, on 9 February 2012 - 12:12 AM, said:

Will you be on the road to MD?

No thankfully I will miss this event while being on the road. Otherwise it could be a nightmare on the turnpikes.

I'll be returning at some point next week weather permitted. The prospects of some sort of storm have me concerned and I might just hold of coming home until its passed. If it goes up the coast I leave MD early , if it hits Detroit I stay.

[Jonger1150]

The only thing I see locally to get excited about is the long range storm that has stayed alive for the last 3 days. I'll be in Houghton riding my snowmobile on the only real snow left in the Midwest.

[Hoosier]

Hoping to squeeze out a half inch here.

[afterimage]

Both the GFS and NAM 12z runs are showing increased moisture from the front passage...might overperform

[Ottawa Blizzard]

The 12z GFS seems to have come in milder for this weekend, as well as next week.

[hm8]

DTX

09.00Z NWP ARRIVED WITH GOOD MODEL CONTINUITY REGARDING THE
MODERATING LOBE OF ARCTIC AIR THAT WILL MOVE INTO SOUTHEASTERN
MICHIGAN ON FRIDAY. THE COMBINATION OF SHARP POTENTIAL VORTICITY
ADVECTION WITH FAVORABLE JET DYNAMICS FOR ASCENT IS LEADING TO A
FORECAST FOR A VERY WELL DEFINED SURFACE TROUGH STRUCTURE AND
FRONTOGENESIS CENTERED AT ROUGHLY 850MB. THE THERMODYNAMIC PROFILE
FOR SNOW IS FAVORABLE WITH SATURATION THROUGH 15KFT IN ADDITION TO
THE -10 TO -20C SLAB PLACED AT THE TOP OF THE MIXED LAYER. THIS ALL
POINTS TO A TIME PERIOD OF ACCUMULATING SNOWFALL ON FRIDAY. THE
UNCERTAINTY WITH THIS SYSTEM...IS WHETHER THE SURFACE TROUGH WILL
SLIP INTO THE CWA LATE FRIDAY MORNING OR WAIT UNTIL LATER IN THE
DAY. THE MODEL SOLUTIONS DIFFER WITH THE ECMWF THE SLOWEST OF THE
SUITE. CONSEQUENTLY...THE ECMWF IS SLOW ENOUGH THAT IS ALLOWS SOME
COLORADO SHORTWAVE ENERGY TO SLIDE IN FRONT OF THE DESCENDING ARCTIC
FRONT. THIS MERGER WOULD LIKELY LEAD TO ENHANCED BAROCLINICITY AND A
DEFORMATION GROWTH RESPONSE LATER INTO FRIDAY EVENING. SO THE REAL
FORECAST DECISION POINT CENTERS ON THIS SURFACE TROUGH PASSAGE AND
TIMING OF SNOWFALL. FROM A SYSTEM PERSPECTIVE...LOOKING AT 1 TO 1.5
INCH AMOUNTS FOR THE MAJORITY OF THE CWA....POSSIBLY 2 TO 2.5 INCH
AMOUNTS IF THE ECMWF/LONGER DURATION DEFORMATION VERIFIES. DID
INCREMENTALLY UPTICK POPS THIS ISSUANCE BUT KEPT A FASTER
TIMING/BULK OF SNOW PRIOR TO 00Z SATURDAY. HIGHS WILL OCCUR AHEAD OF
THE SURFACE TROUGH RANGING IN THE 30S.

[blackrock]

Seriously, why does almost every synoptic event seem to fall apart over Western Michigan? I've seen it over and over again since I moved here. Although the lake helps us with Lake Effect snow, i really wonder if and how it messes up the system snows...it's ridiculous.

[afterimage]

Not too bad, IND ZFP for Muncie area, 2-3" total....

[AppsRunner]

Take 1-3" and run... can TOL make it to 12" by Saturday?

[Toronto4]

Ottawa Blizzard, on 9 February 2012 - 12:02 PM, said:

The 12z GFS seems to have come in milder for this weekend, as well as next week.

Don't forget about the snowfall for Toronto tomorrow night. Environment Canada is calling for an inch, though a tad more is possible, depending on how the deformation band sets up. Also it will be very windy with blowing snow and with falling temperatures into the single digits. Updated forecast from EC is calling for a low of -15C for Toronto early Saturday morning. A high of -7C (upper teens) is forecast for Saturday.

[BeastFromtheEast]

MKE AFD, Nice...

Quote

THERE IS A GOOD CHANCE FOR SNOW SHOWERS JUST BEHIND THE COLD FRONT
FRIDAY MORNING THROUGH FRIDAY AFTERNOON. NOT EXPECTING HIGH
ACCUMULATIONS...ALTHOUGH LAKE ENHANCED SNOW COULD BRING SLIGHTLY
HIGHER ACCUMS TO THE LAKESHORE AREAS. TOTAL SNOWFALL AMOUNTS SHOULD
BE GENERALLY AROUND A HALF INCH...BUT UP TO 1.5 INCHES AT MKE RAC
ENW. STRONG AND GUSTY NORTH WINDS WILL ACCOMPANY THE SNOW SHOWERS ON
FRIDAY. MVFR VSBY WITH OCCASIONAL IFR VSBYS POSSIBLE.

&&

[Geos]

BeastFromtheEast, on 9 February 2012 - 03:53 PM, said:

MKE AFD, Nice...

Nice to see some accumulation even though I'll probably miss on the main lake effect event.

[Nic]

Here we go again with ILN's rediculous advisory criteria, no advisory in Columbus area with advisorys to our south even though we get the same amount.

[Trent]

Wait ... let me get this straight. ILN issues winter weather advisories 36 hours in advance for 1-2" snow events? Guess I'm out of touch with winter weather in southern Ohio ... is that typical?

[Nic]

Trent, on 9 February 2012 - 04:32 PM, said:

Wait ... let me get this straight. ILN issues winter weather advisories 36 hours in advance for 1-2" snow events? Guess I'm out of touch with winter weather in southern Ohio ... is that typical?

They probaly did it because the snow will come in squalls and those can have brief whiteout conditions, and it will be at night mostly.


Most exciting ILN AFD I have seen all winter.

Quote

A WEAK SURFACE LOW WILL DEVELOP AND MOVE ACROSS THE AREA FRIDAY
EVENING WHICH WILL DRAG A COLD FRONT ACROSS OUR AREA. DYNAMIC
LIFT ASSOCIATED WITH THE COLD FRONT...AND APPROACHING UPPER TROUGH
WILL INCREASE SNOW INTENSITY DURING THE LATE EVENING INTO EARLY
SATURDAY MORNING. QPF TRENDS HAVE BEEN INCREASING WITH EACH SET OF
MODEL RUNS OVER THE PAST 2 DAYS...ESPECIALLY FOR FRIDAY NIGHT.
FORECASTED AN EVEN BLEND OF MODEL QPF WITH HPC QPF...YIELDING ONE
TWO TWO TENTHS OF QPF FRIDAY NIGHT. THIS...COMBINED WITH FAVORABLE
LIFT IN THE DENDRITIC GROWTH ZONE...AND FALLING SURFACE
TEMPS...WILL CAUSE INCREASING SNOW RATIOS. THIS SHOULD RESULT IN
WIDESPREAD AMOUNTS AROUND 2 INCHES ACROSS THE SOUTHERN HALF OF THE
FORECAST AREA FRIDAY NIGHT. ACROSS THE NORTH...QPF IS SLIGHTLY
HIGHER...WITH THOSE AREAS EXPECTED TO RECEIVE UP TO 3 INCHES OF
ACCUMULATION. IF CURRENT MODEL TRENDS CONTINUE...AND IF SNOW
PRODUCTION BECOMES MORE EFFICIENT THAN CURRENTLY
ANTICIPATED...THEN ACCUMULATION AMOUNTS ACROSS THE NORTH COULD BE
LOCALLY HIGHER.

[michsnowfreak]

Its certainly looking better than it was a day or so again. Im thinking actually OH may see the best snows. But certainly have a shot at a solid 2" here.

DTX:
WEAK MID LEVEL ISENTROPIC
ASCENT WILL FILL IN BEHIND THE OPEN WAVE PASSING TO OUR SOUTH
TONIGHT WITH RIGHT ENTRANCE JET SUPPORT PROVIDING A BOOST THROUGH
THE MORNING HOURS. WITH PLENTY OF DRY AIR IN PLACE, WEAK ASCENT WILL
DO NOTHING MORE THAN SERVE TO GRADUALLY SATURATE THE COLUMN IN THE
PRE-FRONTAL ENVIRONMENT. THE DURATION OF THE WEAKLY ASCENDING
SOUTHWESTERLY FLOW COULD BE SUFFICIENTLY LONG OVER SOUTHEASTERN
PORTIONS OF THE CWA FOR A LITTLE LIGHT PRECIP TO DEVELOP AS EARLY AS
18Z. OTHERWISE THE BULK OF THE FORCING AND SUBSEQUENT SNOWFALL WILL
INITIALLY OCCUR ALONG THE FRONT ITSELF. MODEL CROSS-SECTIONS
CONTINUE TO INDICATE A 2-3 HOUR PERIOD OF STRONG SFC-850MB FGEN THAT
WILL BE BRIEFLY AUGMENTED BY VERY STRONG CONVERGENCE ALONG THE
LEADING EDGE OF THE FRONTAL BOUNDARY. THIS WILL SUPPORT A QUICK RAMP
UP TO HIGHER INTENSITY SNOW AS A NARROW BUT POTENTIALLY INTENSE BAND
OF SNOW WILL ACCOMPANY THE FRONTAL PASSAGE.

MODEST JET SUPPORT WILL ACCOMPANY THE FRONT FOR MUCH OF THE DAY
BEFORE MUCH STRONGER MID AND UPPER SUPPORT ARRIVE IN THE EVENING.
HERE, THE 12Z GFS HAS TRENDED STRONGLY TOWARD THE SLOWER AND DEEPER
ECMWF SOLUTIONS OF THE THE LAST SEVERAL MODEL CYCLES. THESE
SOLUTIONS FEATURE A SLIGHTLY STRONGER WAVE COMING OUT OF SK AS WELL
AS TODAY`S COLORADO SHORTWAVE ENERGY LIFTING NORTHWARD AHEAD OF THE
TROUGH. THE FORECAST THEREFORE REFLECTS THIS SCENARIO, WITH STRONGER
UPPER LEVEL SUPPORT DEVELOPING BETWEEN 21Z-03Z RESULTING IN ENHANCED
BAROCLINICITY AND A STRONGER DEFORMATION RESPONSE THAT WILL LAST
WELL INTO FRIDAY EVENING. THE NAM/GEM HAVE SHOWN SIMILAR ADJUSTMENTS
BUT OF A NOTICEABLY LESSER MAGNITUDE. HOWEVER, THE RUN OF EXCELLENT
CONTINUITY BY THE ECMWF COUPLED WITH TODAY`S ADJUSTMENT BY THE GFS,
GIVE HIGH CONFIDENCE FOR TRENDING THE FORECAST IN THIS DIRECTION.

THE RESULT IS THAT THE 2 TO 2.5" UPPER END POTENTIAL NOTED IN
OVERNIGHT DISCUSSION IS A MORE PLAUSIBLE SCENARIO THAN IT WAS 12
TO 24 HOURS AGO. THE GFS ACTUALLY ALLOWS THE SYSTEM TO EVOLVE
QUICKLY ENOUGH SO THAT SOUTHEASTERN AREAS, INCLUDING METRO
DETROIT, BASICALLY SEE 2X THE QPF OF AREAS TO THE NORTHWEST. WHILE
CONFIDENCE IN THAT LEVEL OF DETAIL IS NOT THERE YET, THE GFS/ECMWF
ARE IN STILL EXCELLENT AGREEMENT AS FAR AS THE SPATIAL/TEMPORAL
EVOLUTION WITH A BLEND OF THESE TWO MODELS PROVIDING A DESIRABLE
QPF TEMPLATE. AREA BUFKIT SOUNDINGS INDICATE THE DGZ WILL BE
FAVORABLY LOCATED AT THE TOP OF THE MIXED LAYER THROUGH THE EARLY
STAGES OF THE EVENT BEFORE BECOMING CONSIDERABLY DEEPER, AS DEEP
AS 200MB IN VERTICAL EXTENT, AS COLD AIR FILLS IN AND DEFORMATION
BEGINS TO RAMP UP. AT THIS POINT, AVERAGE SNOW RATIOS ARE EXPECTED
TO BE IN THE NEIGHBORHOOD OF 16:1. THUS...THE PREFERRED GUIDANCE
SUGGEST TOTAL SNOW ACCUMULATIONS OF AROUND 2 INCHES FROM I-69
SOUTHWARD. WITH TIME FOR TWO MORE MODEL RUNS BEFORE THE EVENT,
PREFERRED TO STAY CONSERVATIVE ACROSS THE SOUTHEASTERN PORTION OF
THE CWA, INCLUDING DETROIT. HOWEVER, A SWATH OF 2-3" WOULD NOT BE
OUT OF THE QUESTION IF NOTHING CHANGES.

[weatherpsycho]

michsnowfreak, on 9 February 2012 - 05:43 PM, said:

Its certainly looking better than it was a day or so again. Im thinking actually OH may see the best snows. But certainly have a shot at a solid 2" here.

Looks like Bill Deedler may have likely nailed this. In one of his posts he mention this Frontal Squall was a good possibility.

Pretty interesting front. Heres to hoping for a wind blown 2" or more tomorrow

[DAFF]

The worst part is that this might be the biggest snow since March 2011.... Thank goodness for the snow better late than never. Is there a way someone can explain Rapid refresh or another qualitative snow forcasting tool and how to use it for our region. I have tried the one on NOAA but is always seems wrong... or incomplete for the time
period.

[mnweather]

Nice band of heavy snow here with the frontal passage.

[michsnowfreak]

DAFF, on 9 February 2012 - 07:59 PM, said:

The worst part is that this might be the biggest snow since March 2011.... Thank goodness for the snow better late than never. Is there a way someone can explain Rapid refresh or another qualitative snow forcasting tool and how to use it for our region. I have tried the one on NOAA but is always seems wrong... or incomplete for the time
period.

It will be close, but it is possible that this would be the biggest snow of the season so far. Though DTW has a biggest snow so far of 3.4" (Dec 5th) with a season total of 15.6", my biggest snow has been 2.5" (set twice, Jan 14 and Jan 21/22) on a season-to-date of 16.3". By comparison, last winter I had EIGHT snowstorms drop OVER 4 inches (two of which were over 10")! A friend who lives in Farmington Hills (NW of Detroit) is at 18.4" on the season but his biggest single storm is 2.1" (Dec 9th)! So as you can see, it has certainly been nickel and dime this year, perhaps even moreso than usual

[michsnowfreak]

mnweather, on 9 February 2012 - 08:09 PM, said:

Nice band of heavy snow here with the frontal passage.

Fropa is probably some 20 hours away, but that is good news to hear upstream.

[Ajdos]

00z Nam looks really nice for S/E Mi. 2-4" my guess.

[Ajdos]

I guess 696 north looking good based on 00z NAM

Attached Files

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[Powerball]

One thing I can say for sure, the 00z NAM's solution sure as hell better not be the outcome.

[weatherpsycho]

Ajdos, on 9 February 2012 - 09:38 PM, said:

I guess 696 north looking good based on 00z NAM

Wow. I would take that!

[Chicago WX]

Heh. NAM "scorches" the low levels here for a time. Below the somewhat odd result.

[Hoosier]

Chicago WX, on 9 February 2012 - 10:25 PM, said:

Heh. NAM "scorches" the low levels here for a time. Below the somewhat odd result.
http://img651.imageshack.us/img651/710/usaptypesfc022.gif

I'd be a tad more bullish on amounts (and I do mean a tad) if we didn't have thermal questions. I think we probably stay at an inch or less.

[Chicago WX]

Hoosier, on 9 February 2012 - 10:31 PM, said:

I'd be a tad more bullish on amounts (and I do mean a tad) if we didn't have thermal questions. I think we probably stay at an inch or less.

I'm not sure I buy the warmer NAM...but either way, an inch is probably about the best case.

[michsnowfreak]

Powerball, on 9 February 2012 - 10:04 PM, said:

One thing I can say for sure, the 00z NAM's solution sure as hell better not be the outcome.

The 00z NAM verbatum still gives 0.17" qpf to DTW and 0.21" to DET, among the best of any NAM run. Also gives 0.36" to PTK. Remember a few days ago qpf was looking in the 0.03-0.05" range. That said, the 00z NAM looks very funky and the NAM has had tons of run to run continuity problems, so Im guessing its an outlier til the other guidance all comes in. I think SE MI is good for a 1-3 inch snowfall.