March Medium/Long Range Discussion

[brooklynwx99]

we can see an amped solution like the GFS, don’t get me wrong

however, acting like an amped solution is a foregone conclusion is a bit ridiculous at this range. look how Monday’s storm has trended over the last couple of days for NJ… way more confluence over the last two model cycles. anything from a cutter to suppression to a MECS is on the table, as per usual 6 days out

[fujiwara79]

UKMET looks very close to CMC at H5.

[psuhoffman]

[Weather Will]

WB 0Z EURO 

[Maestrobjwa]

Just now, psuhoffman said:

Tick, tick, north...Wouldn't surprise me if we're in the gray area by 0z (or earlier) tomorrow, lol (I'd love to be wrong, of course)

[Weather Will]

Still in the game, as suspected the tracking game for this storm did not end at 0Z…

[Weather Will]

All three globals at Day WB 0Z at 7pm Fri.

[Weather Will]

Does an expert on GFS have an opinion on whether it has a bias to be slow to pick up on blocking or is it correct in forecasting a weaker block?

[Maestrobjwa]

8 minutes ago, Weather Will said:

Does an expert on GFS have an opinion on whether it has a bias to be slow to pick up on blocking or is it correct in forecasting a weaker block?

Sounds like a question for a GFSologist

[RedSky]

1 minute ago, Maestrobjwa said:

Sounds like a question for a GFSologist

With some experience in proctology

[jayyy]

Until the new CMC and Euro comes out. Lol

Nope


.

[jayyy]

looking at the glass half full, fuck yeah
looking at the glass half empty, bullseye 5 days out never works out

Models have honed in on general solutions around day 5 all winter long. Especially at h5. The problem is that every threat has trended the wrong way in that timeframe and eventually failed. This time we’re seeing the opposite (aside from the GFS) occur, where most models are getting more bullish as we get closer. The euro and CMC at D5-6 getting significantly better is a good sign, especially with ensemble support.

It is nice to see the hit camp be bigger than the fail camp for a change. Still about 72 hours out from getting too excited about this though given our propensity to fail this winter.

[jayyy]

00z ICON for shits and giggles. What a bomb


.

[BristowWx]

2 hours ago, jayyy said:

00z ICON for shits and giggles. What a bomb


.

If the 6z ICON went past 120 it would have been not good compared to this run.  It’s warmer and norther

[BristowWx]

Welp…Going back to sleep now and dream of next winter

[Weather Will]

WB 6Z GFS… may do nothing to change the endgame but the pressure maps show a tick SE in track,  we will see if it is a trend at 12Z.

[Weather Will]

OZ EPS mean was an improvement over 18Z.

[Terpeast]

I noticed the tick in slp too. If one camp is going to cave to the other, it will be within the day or so. 

[CAPE]

7 hours ago, Ralph Wiggum said:

Hats off to @CAPEif this in fact ends up a cutter. Dont love the h5 trends so far.

I am not predicting it will be. I just thought the most likely way we fail would again be a NW track. The setup is clearly better than what we have had, but the block is just getting established. The location and timing of the NS vorticity across southern Canada is going to influence the track of the wave and there are still differences there, and then there is the next western trough with additional upper level energy digging in behind, also impacting the track. Always issues. We still can't know yet. 

[Terpeast]

Solid disco in LWX AFD:

 

Thereafter, forecast uncertainty begins to increase as we move into Thursday and Friday. On Wednesday, a strong cyclone in the Gulf of Alaska will build a downstream ridge, which is modeled to progress
eastward into the CONUS with an appreciable forward speed. As this ridge builds downstream, it will perturb the downstream waveguide, which has been relatively stagnant over the past week. In response to
the ridgebuilding, troughing will dig into the Desert Southwest/Four Corners region Wednesday night, and then progress eastward onto the
Southern Plains Thursday into Thursday night. Meanwhile, the upper ridge will progress eastward and interact with a downstream upper low over Hudson Bay. Exactly how this complex process plays out will
have a major impact on our forecast. The 00z Euro and 00z Canadian have the ridge progress eastward at a higher forward speed than the
trough within the southern stream. As a result, the ridge cuts overtop of the shortwave trough as it closes off, effectively keeping it suppressed to the south as it progresses eastward. In
these scenarios, the potent upper level shortwave progresses directly overhead, with an intense area of low pressure at the surface progressing to our south. The 00z GFS on the other hand,
doesn`t have the upper ridge build overtop the southern end of the trough, and maintains one coherent north-south oriented wave from Canada down into the Southern Plains. This scenario allows the southern stream shortwave to amplify further and gain more latitude as it progresses toward the east. This scenario results in a very intense area of low pressure tracking off to our north and west.

Such a scenario would place us on the warm side of the system, and would result in temperatures climbing into the 60s or 70s, along with heavy rainfall, and potentially even severe thunderstorms. The scenario depicted by the Euro and Canadian on the other hand would produce a significant amount of snowfall across the area, with temperatures holding in the 30s.

In both of these scenarios, Thursday would have relatively quiet weather, with northwest winds, and potentially a few showers. The main forecast uncertainty on Thursday would lie in the high temperatures forecast. Ensemble guidance has highs on Thursday ranging from the 40s to the 70s.  The higher impact weather, whether
it be in the form of heavy rain and thunderstorms, or snow, would move in on Friday and last into Friday night.

With such a highly uncertain and complex forecast, it`s important to think probabilistically. The deterministic models described above span the phase space of potential outcomes outlined in the ensemble guidance. The system being suppressed far to our south and completely missing us (as some ensemble members showed yesterday) appears to be off the table. The two main scenarios now entail the low passing to our north and west, and us ending up on the warm side of the system, and then the low passing to our south, and us ending up with wintry precipitation on the cool side of the system.

In terms of temperatures, these solutions range from highs in the 70s, to highs in the 30s. As a result, our deterministic forecast (that you see in the point and click forecast on our website) is a middle of the road solution and calls for highs in the 40s/50s, and rain across much of the area (since you can`t have snow with temperatures in the 50s). Nonetheless, the chance for snow is a very real one.

Digging a bit into the probabilistic phase space, and individual ensembles, both the EPS and GEPS trended colder and snowier with the 00z model cycle, especially across the northern half of the forecast area. The EPS and GEPS now shows a greater than 50 percent chance for accumulating snow across nearly all of the forecast area, as well as a greater than 50 percent chance for more than a half foot of snow across far northwestern portions of the forecast area (Potomac Highlands and western Maryland). The GEFS on the other hand stand in stark contrast to the EPS and GEFS. The GEFS actually trended warmer, and less snowy, with very low probabilities for any snow, let alone significant snow. Oftentimes, the GEFS tends to follow trends in the GFS very closely, so this trend is somewhat unsurprising. In all of the respective ensembles, probabilities for snow are greater further off toward the north and west, and lesser as you progress further off toward the south and east. At the moment, this is a very challenging and highly uncertain forecast for
Friday. We`ll continue to monitor trends and adjust our forecast accordingly as we progress through the week.

[katabatic]

1 minute ago, Terpeast said:

Solid disco in LWX AFD:

 

Thereafter, forecast uncertainty begins to increase as we move into
Thursday and Friday. On Wednesday, a strong cyclone in the Gulf of
Alaska will build a downstream ridge, which is modeled to progress
eastward into the CONUS with an appreciable forward speed. As this
ridge builds downstream, it will perturb the downstream waveguide,
which has been relatively stagnant over the past week. In response to
the ridgebuilding, troughing will dig into the Desert Southwest/Four
Corners region Wednesday night, and then progress eastward onto the
Southern Plains Thursday into Thursday night. Meanwhile, the upper
ridge will progress eastward and interact with a downstream upper
low over Hudson Bay. Exactly how this complex process plays out will
have a major impact on our forecast. The 00z Euro and 00z Canadian
have the ridge progress eastward at a higher forward speed than the
trough within the southern stream. As a result, the ridge cuts
overtop of the shortwave trough as it closes off, effectively
keeping it suppressed to the south as it progresses eastward. In
these scenarios, the potent upper level shortwave progresses
directly overhead, with an intense area of low pressure at the
surface progressing to our south. The 00z GFS on the other hand,
doesn`t have the upper ridge build overtop the southern end of the
trough, and maintains one coherent north-south oriented wave from
Canada down into the Southern Plains. This scenario allows the
southern stream shortwave to amplify further and gain more latitude
as it progresses toward the east. This scenario results in a very
intense area of low pressure tracking off to our north and west.
Such a scenario would place us on the warm side of the system, and
would result in temperatures climbing into the 60s or 70s, along
with heavy rainfall, and potentially even severe thunderstorms. The
scenario depicted by the Euro and Canadian on the other hand would
produce a significant amount of snowfall across the area, with
temperatures holding in the 30s.

In both of these scenarios, Thursday would have relatively quiet
weather, with northwest winds, and potentially a few showers. The
main forecast uncertainty on Thursday would lie in the high
temperatures forecast. Ensemble guidance has highs on Thursday
ranging from the 40s to the 70s.  The higher impact weather, whether
it be in the form of heavy rain and thunderstorms, or snow, would
move in on Friday and last into Friday night.

With such a highly uncertain and complex forecast, it`s important to
think probabilistically. The deterministic models described above
span the phase space of potential outcomes outlined in the ensemble
guidance. The system being suppressed far to our south and
completely missing us (as some ensemble members showed yesterday)
appears to be off the table. The two main scenarios now entail the
low passing to our north and west, and us ending up on the warm
side of the system, and then the low passing to our south, and us
ending up with wintry precipitation on the cool side of the system.
In terms of temperatures, these solutions range from highs in the
70s, to highs in the 30s. As a result, our deterministic forecast
(that you see in the point and click forecast on our website) is a
middle of the road solution and calls for highs in the 40s/50s, and
rain across much of the area (since you can`t have snow with
temperatures in the 50s). Nonetheless, the chance for snow is a very
real one.

Digging a bit into the probabilistic phase space, and individual
ensembles, both the EPS and GEPS trended colder and snowier with
the 00z model cycle, especially across the northern half of the
forecast area. The EPS and GEPS now shows a greater than 50 percent
chance for accumulating snow across nearly all of the forecast area,
as well as a greater than 50 percent chance for more than a half
foot of snow across far northwestern portions of the forecast area
(Potomac Highlands and western Maryland). The GEFS on the other hand
stand in stark contrast to the EPS and GEFS. The GEFS actually
trended warmer, and less snowy, with very low probabilities for any
snow, let alone significant snow. Oftentimes, the GEFS tends to
follow trends in the GFS very closely, so this trend is somewhat
unsurprising. In all of the respective ensembles, probabilities for
snow are greater further off toward the north and west, and lesser
as you progress further off toward the south and east. At the
moment, this is a very challenging and highly uncertain forecast for
Friday. We`ll continue to monitor trends and adjust our forecast
accordingly as we progress through the week.

All solutions show us drying out on Saturday as winds turn
northwesterly behind the departing low.

They’re just as excited to finally have something to write about as we are to track. 

[Weather Will]

WB GEPS 0Z compared to 12Z yesterday.

[Weather Will]

WB 6Z GEFS

[CAPE]

My wag at this point is that this will end up favorably, although maybe not all snow, for places inland and further NW in our region. For the lowlands it looks more problematic because of the marginal temps. Given the advertised lack of HP to the north on guidance, even a track along/just off the coast would be iffy for eastern areas. This has been a notable issue in recent winters in marginal cold situations.

[Weather Will]

Stark differences remain between WB 6Z GEFS and 0Z EPS.  GEFS maintains its NW, rainy track.  It will be interesting to see if EPS holds its colder, snowy solution at 6Z.

[Weather Will]

WB 0Z EPS still showing our Hail Mary, mid March period so the end of the week is still not the last chance.

[Buddy1987]

44 minutes ago, CAPE said:

My wag at this point is that this will end up favorably, although maybe not all snow, for places inland and further NW in our region. For the lowlands it looks more problematic because of the marginal temps. Given the advertised lack of HP to the north on guidance, even a track along/ off the coast would be iffy for eastern areas. This has been a notable issue in recent winters in marginal cold situations.

I agree here. Too amped for my area down this way but I could see @clskinsfan and @WinterWxLuvrliking this setup, although the northern MD and southern PA crew are more than in it at this stage as well. Hopefully it trends south and east so everyone is happy but the way this year has gone I am not holding out much hope. 

[Ji]

This storm is now about 120 hours out....in 99% of situations...the euro would not make any significant shifts now....especially if it was showing a cutter or rain or suppressed for us lol

Sent from my SM-A515U using Tapatalk

[Interstate]

1 minute ago, Ji said:

This storm is now about 120 hours out....in 99% of situations...the euro would not make any significant shifts now....especially if it was showing a cutter or rain or suppressed for us lol

Sent from my SM-A515U using Tapatalk
 

And then they updated it 

[AtlanticWx]

eps shifting se at 0z was good, hoping it keeps it up