Apr 21-23 MidAtl/NE Storm, Reality: Short Range [0-4 days] Options

[Mike W IN herkim...]

The Nws introduced the word snow into my forecast

Sunday Night: A chance of rain before 5am, then a chance of rain and snow. Mostly cloudy, with a low around 35. Chance of precipitation is 40%.

Monday: A chance of rain and snow showers. Mostly cloudy, with a high near 51. Chance of precipitation is 50%.

Monday Night: A chance of rain and snow showers. Mostly cloudy, with a low around 34. Chance of precipitation is 40%.

Tuesday: A chance of rain and snow showers. Mostly cloudy, with a high near 50. Chance of precipitation is 30%.

Tuesday Night: A chance of rain and snow showers. Mostly cloudy, with a low around 34. Chance of precipitation is 30%

http://forecast.weather.gov/MapClick.php?C...mp;lon=-74.9928

This post has been edited by Mike W IN herkimer: Apr 19 2012, 04:05 PM

[NorEaster07]

In case anyone remembers, for the Feb 23-24 storm the ECM was the most amplified model and was the last one to become less amplified -.

I was trying to remember which last storm who had the more amplified solution and then it gave into the other major model.. But I do remember one storm where the Euro was right on the snow totals from this far out. Not sure if it was the same storm we're thinking, but I dont have the time to check all that. I think it was Feb 29th when it was north of us?

Anyway - Obviously one will be wrong. lol How about a middle.

[NYCSuburbs]

I was trying to remember which last storm who had the more amplified solution and then it gave into the other major model.. But I do remember one storm where the Euro was right on the snow totals from this far out. Not sure if it was the same storm we're thinking, but I dont have the time to check all that. I think it was Feb 29th when it was north of us?

Anyway - Obviously one will be wrong. lol How about a middle.

Feb 29th it showed a major snowstorm for NE NJ and was the southernmost model - I got nothing

One I can think of is the storm around 2/20 or so in the Southeast, where it handled it best from the medium range into the short range. When storms this winter involved phasing, the ECM seems to have frequently overdone it though. I agree with the last statement; one or more models will be wrong here, and IMO the GFS/NAM will be on the east side and the ECM on the west. If I had to give an instant forecast, I would go with something a little west of the CMC.

[The Snowman]

Verification Scores for the ECMWF and GFS over the past many runs. Notice how the ECMWF has a dominant hold over this comparison. This is just me, but considering how it first pointed out the 2011 Groundhog Day Blizzard, and won the 2011 October snowstorm, the ECMWF and ECMWF Ensembles may have a pretty good fight going for themselves.
But hey- i'm from the Midwest. What do I know?

Verifications from PoliClimate

Quick write-up on my blog on the verification scores.

This post has been edited by The Snowman: Apr 19 2012, 04:15 PM

[NYCSuburbs]

18z DGEX starting to run... comparing the latest 18z NAM (hour 72) to where the 6z DGEX started (NAM hour 84), the southern vort is north and stronger, but the northern stream digs a bit less. Hard to tell exactly what'll happen, but it should be west of the 6z run when it stayed well to the east.

[Mike W IN herkim...]

KALB

SAT-SAT NT...AFOREMENTIONED COLD FRONT WILL MOVE E SAT...BUT SOME
UNCERTAINTY AS TO HOW FAST IT MOVES E. MODELS DEPCIT AN ANAFRONTAL
STRUCTURE TO THIS FRONT...WITH MOST RAIN/SHOWERS ON COOL SIDE OF
BOUNDARY. DURING THE MORNING...HAVE GENERALLY KEPT HIGHEST POPS
FOR AREAS WEST OF THE HUDSON RIVER VALLEY...SLOWLY INCREASING FROM
W TO E FROM MID MORNING INTO THE AFTERNOON HOURS...AND POSSIBLY
NOT UNTIL LATE AFTERNOON/EARLY EVENING ACROSS FAR S/E AREAS.
ASSUMING THIS SLIGHTLY SLOWER FORWARD MOVEMENT OF THE FRONT...HAVE
GENERALLY SIDED WITH THE WARMER MAV MOS FOR MAXES...WITH 65-70
WITHIN AND E OF THE HUDSON RIVER VALLEY...AND 50S TO LOWER 60S
FURTHER W. IN MANY AREAS...TEMPS MAY ACTUALLY PEAK AROUND
MIDDAY...BEFORE FALLING DURING THE AFTERNOON HOURS. FOR SAT
NT...EXPECT SOME SHOWERS TO LINGER EARLY...MAINLY FROM ALBANY S
AND E...WHERE CHC POPS ARE INDICATED. EXPECT MUCH COOLER TEMPS SAT
NT...ALTHOUGH HAVE SIDED A BIT HIGHER THAN THE MET MOS...WITH
35-40 ACROSS THE HUDSON RIVER VALLEY...COOLEST NORTH...AND UPPER
20S TO MID 30S ACROSS THE SOUTHERN ADIRONDACKS AND WESTERN MOHAWK
VALLEY REGION.

.LONG TERM /SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
HPC GUIDANCE DUE TO MODEL UNCERTAINTIES. A WET PATTERN SHOULD
CONTINUE WELL INTO THE WORK WEEK. LOW PRESSURE DEEPENING AND
RIDING NORTH ALONG A STATIONARY FRONT AT THE START OF NEXT WEEK
SHOULD PROVIDE THE IMPETUS FOR RAIN...WITH MIXED PRECIPITATION OR
SNOW POSSIBLE IN THE HIGHER ELEVATIONS. THE LOW MAY BECOME CUT
OFF OVER SOUTHERN QUEBEC BY TUESDAY...WITH CONTINUED MOSTLY
CLOUDY AND SHOWERY CONDITIONS...MAINLY ACROSS THE NORTHERN ZONES.
AS THE LOW LIFTS NORTH AND WEAKENS...POPS DIMINISH FURTHER...TO
SLGT CHC EVERYWHERE BY THURSDAY...BY WHICH TIME SUNSHINE
INCREASES....AND HIGH TEMPERATURES BOUNCE BACK INTO THE 50S AND
60S. THE COOLEST DAY WILL BE MONDAY...WITH HIGHS PRIMARILY IN THE
LOW 40S TO MID 50S RANGE.

http://forecast.weather.gov/product.php?si...mp;highlight=on

[jdrenken]

Verification Scores for the ECMWF and GFS over the past many runs. Notice how the ECMWF has a dominant hold over this comparison. This is just me, but considering how it first pointed out the 2011 Groundhog Day Blizzard, and won the 2011 October snowstorm, the ECMWF and ECMWF Ensembles may have a pretty good fight going for themselves.
But hey- i'm from the Midwest. What do I know?

Verifications from PoliClimate

Quick write-up on my blog on the verification scores.

It's also about the trends. For instance, are we going to be in a 'spike' or are we heading into a 'valley' for this storm. Keep in mind also the sample of the graphs. Are they for the NOAM, NOHM, or CONUS.

Here is the HPC Day 5 verifications specific to the CONUS...


EDIT: Going further...the verifications are for the track, not the specifics. How many times were the tracks awesome, but not enough cold air this winter?

[NYCSuburbs]

Interesting - at hour 54 the 18z GFS seems to be more separated with the northern stream and the southern s/w looking at 500mb, but at the surface they almost seem to be a bit closer. Either way it doesn't look like a jump to the foreign models; and the short range battle continues...

This post has been edited by NYCSuburbs: Apr 19 2012, 05:05 PM

[paletitsnow63]

12Z Euro Ensembles at H96 & H120:

Attached thumbnail(s)

 

[NYCSuburbs]

12Z Euro Ensembles at H96 & H120:

We should've had this during January, not in April. The only thing possibly worse than a winter like this followed by an active spring pattern is a continuation of this increasingly chilly/amplified pattern through the fall followed by a reversal to another zonal flow next winter - I would lose if it we get 2 unbelievably terrible winters in a row...

[gulfofslides]

12Z Euro Ensembles at H96 & H120:

That is not going to happen

[NYCSuburbs]

That is not going to happen

Maybe not the level of amplification that the 2nd frame has, but the low could easily be positioned near the first frame.

[NorEaster07]

So 18z GFS shifed a tad west again and gives these results for snow.

Small band of 8-10 in NH and Maine. 4-6 all of NH, parts of VT and northern MA.

[NorEaster07]

Last 4 runs of GFS. Obvious West trend and also stronger.

[LoveNYCSnow]

hard to believe I'm back on here in late April but this storm has me intriqued, a potential bomb of a storm with potential for heavy wet snow inland.

[Superstorm93]

RPM has less than a half inch of rain for this storm lol

12z ECMWF had 3-4"

[grandpaboy]

hard to believe I'm back on here in late April but this storm has me intriqued, a potential bomb of a storm with potential for heavy wet snow inland.

You should be with us ALL year round here.............


If the 12z EURO comes true.........forget tree snapping snow.......tree snapping wind........Leaves just busted out on the trees here

winds approaching 45 knots along the coast per the EURO

This post has been edited by grandpaboy: Apr 19 2012, 08:04 PM

[NYCSuburbs]

You should be with us ALL year round here.............


If the 12z EURO comes true.........forget tree snapping snow.......tree snapping wind........Leaves just busted out on the trees here

winds approaching 45 knots along the coast per the EURO

Still could easily end up as even a moderate wet snowstorm inland as long as the storm aplifies and tracks NNW.

[LoveNYCSnow]

You should be with us ALL year round here.............
If the 12z EURO comes true.........forget tree snapping snow.......tree snapping wind........Leaves just busted out on the trees here

winds approaching 45 knots along the coast per the EURO

lol thats true but there hasn't really been much to follow storm wise at all, so a major storm+the potential for wintry weather in parts of the region is like a double whammy, if it even happens, but looking at the 12Z Euro and the trend of the 18Z GFS a major storm for at least parts of the reason is looking more likely.

[grandpaboy]

This is not drought busting rains..........like it was showing a few days ago.....