February 28-March 1st rainstorm for the coastal areas?

[krysof]

I respect your judgment, I will not favor one scenario significantly until models really come together.

[EXTONPA]

the latest GFS is markedly further east with the storm; it makes sense with the overall pattern....I really think the dominate feature will be coastal low; once again, New England may see the brunt of this storm.

[IndianaJonesDDT]

the latest GFS is markedly further east with the storm; it makes sense with the overall pattern....I really think the dominate feature will be coastal low; once again, New England may see the brunt of this storm.

does that mean Annapolis, Maryland will get anything other than a rain or mix?

[donsutherland1]

Just a quick note...

The 2/26 0z run of the GFS maintained a slow but steady trend to the east. Slowly the GFS is becoming more consistent with its ensemble mean and the ECMWF.

Here are comparative maps for 3/1 0z for the most recent four runs of the GFS:

[krysof]

now that I compare the forecasts, things have changed with the gfs, almost significantly since the 6z models

[EXTONPA]

I think many folks in the I95 corridor have good chance of getting 1 foot or more out of this storm

[yoda]

No, the NAM isn't east. the Apps low is ALWAYS the main low. The GFS needs a moderate Westward shift and it is there, the missing piece so to speak. The GGEM is the GFS but more east. The NAM is a Apps solution.

Intill that "final piece" comes into these models view, they will be wrong each and every time.

Let me be clear, I DO NOT agree with the Nams West Slope of Apps track, but the other models simply aren't phasing as the pattern dictates, thus leading to failure with runs to far east and missing the 500mb low. Don tries to say how in 67 there was a storm that "missed" the 500mb low, but not when it is closing off like that(which the 67 GL low never did), IT rules the roost. The southern low MUST pull back. Intill I see that, A blend of the NAM and GGEM/European is the best I can do(or a slightly more westward GFS)

Huh? The GGEM/CMC/EC/GFS/UKIE/MM5 all suggest the POTENTIAL for big I95 snows...

[donsutherland1]

SnowGod,

In ordinary situations, the 500 mb low would likely capture and reel the surface low inland. In the current extraordinary blocking situation this is a far more difficult proposition. Moreover, the idea simply does not fit the limited number of cases with extreme blocks (NAO: -5.500 or below)/SOI- during weak El Niño or even Neutral ENSO seasons.

But aside from this historic information, the highly-skilled operational ECMWF, ECMWF ensembles and GFS ensembles all favor the offshore/coastal track. In my view, this is no accident and I believe that this set of models/ensembles is more or less correctly handling the possible phasing situation. In fact, it fits what one would reasonably expect synoptically from an extreme blocking situation and the current setup that is now in place.

This combination of climatology, most skilled medium-range operational model, and ensembles is a strong one. Recall, just a week ago, there was speculation that the PV would would retreat to Siberia. The above consensus suggested that was not the most likely nor even likely outcome. It did not retreat to Siberia.

Just over two weeks ago, there was speculation that the warm pattern would continue in the East. Yet, the above combination also strongly suggested the big pattern change that has now occurred.

Therefore, I am reasonably confident that the offshore/coastal track somewhere near the ECMWF perhaps a tad west of it will ultimately be the track to verify. There are a number of critical pieces to the puzzle, of which the 500 mb low is just one. In my view, the extraordinary block (16th strongest block out of more than 20,000 cases) is the dominant feature that will define this synoptic pattern. Thus, until the surface low has tracked into or off eastern New England I do not believe it will be bending west of north; if history with such situations is again relevant, the block simply won't permit it.

[Ed Spacer]

I'm very concerned about the temperature situation for the DC Metro area. I don't really trust weather.com, but they and the local mets have temps in the high 30's, of course I don't think they have taken the 0z into account yet. From what krysof says with the movement east, and what I seem to be understanding, that if a movement to the east does occurs and stays, it will likely allow cold air to penetrate and make the precip snow? Man, this is stresss!!!

No,stress,buddy....catching new models have highs mid 30s here in DE tomorrow,and LOW 30s Sunday.....

[donsutherland1]

12z NAM: Possible First Step Toward ECMWF/Ensemble Alliance...



Notice two quick things:

1) The western low has been pushed back to central Ohio vs. western PA/NY (more separation between systems).
2) For the first time, a low near the coast (albeit in SE PA) is depicted.

For me, this is not a surprise and could be the start of a trend toward the aforementioned model-ensemble alliance given the synoptic setup. This morning's NAO was -5.688 (still extreme). In my view, it is this extreme block that will define the pattern.

Very wisely in the face of the evolving situation, NWSFO, Sterling issued the following Special Weather Statement:

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
934 AM EST SAT FEB 26 2005

DCZ001-MDZ004>007-009>011-013-014-016>018-VAZ036>042-050>057-262031-
ALBEMARLE VA-ANNE ARUNDEL MD-ARLINGTON/FALLS CHURCH/ALEXANDRIA VA-
CALVERT MD-CARROLL MD-CHARLES MD-CULPEPER VA-DISTRICT OF COLUMBIA DC-
FAIRFAX VA-FAUQUIER VA-FREDERICK MD-GREENE VA-HARFORD MD-HOWARD MD-
KING GEORGE VA-LOUDOUN VA-MADISON VA-MONTGOMERY MD-NELSON VA-
NORTHERN BALTIMORE MD-ORANGE VA-PRINCE GEORGES MD-
PRINCE WILLIAM/MANASSAS/MANASSAS PARK VA-RAPPAHANNOCK VA-
SOUTHERN BALTIMORE MD-SPOTSYLVANIA VA-ST. MARYS MD-STAFFORD VA-
934 AM EST SAT FEB 26 2005

...WINTER STORM POSSIBLE SUNDAY NIGHT INTO MONDAY...

A STRONG STORM SYSTEM IS FORECAST TO DEVELOP OVER THE SOUTHEASTERN
UNITED STATES ON SUNDAY...AND THEN MOVE UP THE MID ATLANTIC COAST ON
MONDAY. THIS STORM WILL BRING THE POTENTIAL FOR MODERATE TO HEAVY
PRECIPITATION ACROSS THE REGION SUNDAY NIGHT INTO MONDAY.

THE CURRENT FORECAST CALLS FOR PRECIPITATION TO START AS SNOW SHORTLY
AFTER MIDNIGHT EARLY MONDAY MORNING...THEN FOR SNOW TO MIX WITH AND
PERHAPS CHANGE TO RAIN DURING THE DAY MONDAY...ESPECIALLY ALONG AND
EAST OF THE I-95 CORRIDOR. HOWEVER...THE EXACT TRACK OF THIS STORM
REMAINS UNCERTAIN. IF THIS SYSTEM TRACKS FURTHER EAST THAN CURRENTLY
FORECAST...PRECIPITATION WOULD PRIMARILY FALL IN THE FORM OF
SNOW...AND THIS STORM COULD BRING SIGNIFICANT AMOUNTS OF SNOW TO THE
REGION.

[krysof]

a little eastward shift would make a huge difference and its possible that it will happen, several models depict this, the reason they don't completely say it will is because of the nam models, they are trying to make forecasts inbetween the two scenarios, and the nam is very stubborn on this storm. The nam model doesn't care what the other models say, it just follows what it wants to believe in. Eventually, and its already starting to happen, it will have no choice but to give in to the other models and agree.

[Becka]

So Don, what amount for NE MD?

Thanks,

Becka

[Karebear]

Okay not to sound stupid here, but the way I am understanding all of this is the further it goes out to sea the more snow we will see in the Baltimore area? The mets here which I saw somebody already point out are calling for an all rain event. Does anybody have any clear ideas on what is going to happen or is it to soon to tell at this point? Sorry if I sound sarcastic but it is so nerve wracking not knowing what is going to happen. The weather channel still does not have a clue on this thing either. Thanks in advance and again sorry if I sound sarcastic. I'm trying to understand all of this. It doesn't help when I can't make sense of the maps. You guys and gals are great at explaining everything. I compare the maps as I read your discussions but it is all to confusing to me. Again thanks.

Karebear

[Stephanie]

If the storm is further to the east of the coast than what the models have been saying, then it does mean more snow for the big cities along I-95. Being to the north or west of a system like this, it means that we're on the "cold" side of the storm.

[krysof]

it's becoming more likely that the I-95 corridor may say the big snows

[Brent]

it's becoming more likely that the I-95 corridor may say the big snows

Where is Captain Obvious when you need him?