Re: 11/26 Strong Coastal Storm Possible

by **aiannone** Mon Nov 24, 2014 11:27 am

Meteorologist on Americanwx
"Yup, this is a very dangerous forecast scenario near the coast, the boundary layer is borderline but the wind direction is good, any sort of heavy precipitation rates and its going to be snow...I'm glad I'll be off and not forecasting this one."

by **sroc4** Mon Nov 24, 2014 11:29 am

Im not posting snow map until tomorrow

by **Snow88** Mon Nov 24, 2014 11:29 am

12z GGEM looks nice for the area. Benchmark hit.

11/26 Strong Coastal Storm Possible - Page 21 20hwoz7

11/26 Strong Coastal Storm Possible - Page 21 2zghxj7

by **Frank_Wx** Mon Nov 24, 2014 11:32 am

sroc4 wrote:Intersting thought by Johnathan Carr on FB Frank.

"It's hard to hold your forecast ground through the easterly bias of the GFS in the long range and then the ECM westerly/amped bias in the mid-range. Lets keep something in mind though...this sub 980mb storm over the lakes is the key primary driver of today's warm temperatures. For all the warmth it's pulling up from the south, it's also pulling cold down on the backside with equal energy. With that being said...the warmer today is, the colder and stronger the Wednesday temp crash will be.
Given that the secondary coastal is almost a natural derivative (energy-wise) of the primary lakes low now...that is why I'm leaning with more of a ECM ENS/GFS track over the ECM OP"

Frank also look at the HP over the N Plains/S Canada by hr 54 on the GFS, It is a strong 1035+mb HP that is building east over the top of this storm as it passes the DelMarVa and to the BM by hr 60. The other thing I have noticed is the weak LP on the GFS by hr 54-60 is much further south over the Tenn valley. Prev when the coastal was modeled around the delmarva/BM latitude that weaker LP was being modeled up by the GL. With it further south it seems to effectively open a gate for some colder air to come into the back side of this thing quicker. At least as per the GFS. The key will be todays 12z Euro look. if it comes east and that secondary LP is in a similar position in the Tenn valley and that HP is building in watch out. Because honestly I think the models are underestimating the LP intensity as it approaches the BM as it has done all season so far.

Check this out Doc

11/26 Strong Coastal Storm Possible - Page 21 Gfs_bull

I circled both the polar s/w and stj s/w. If you look at the H5 vort maps for yourself and loop it, you will notice the polar s/w actually closes off at one point over the Midwest. That is NOT what you want to see in a coastal storm. You want a clean phase. The STJ s/w shoots up the coast and brings up the warm southern air with it. There is no dynamics because there is not a clean phase. The trough broadens up.

I do not see an HP to the north. Even if there is, we need it over Maine. Not northwest of us.

by **aiannone** Mon Nov 24, 2014 11:33 am

And the CRAS says 60'S AND RAIN FOR ALL!!!!!
11/26 Strong Coastal Storm Possible - Page 21 Cras4510

by **Frank_Wx** Mon Nov 24, 2014 11:35 am

Snow88 wrote:12z GGEM looks nice for the area. Benchmark hit.

Anthony, you have to look at better maps. Who cares if it is a BM track if ALL the layers are warm.

12z GGEM

11/26 Strong Coastal Storm Possible - Page 21 CMC_MSLPThickQPF_ne_f51

11/26 Strong Coastal Storm Possible - Page 21 CMC_MSLPThickQPF_ne_f51

11/26 Strong Coastal Storm Possible - Page 21 CMC_MSLPThickQPF_ne_f54

11/26 Strong Coastal Storm Possible - Page 21 CMC_MSLPThickQPF_ne_f57

by **Frank_Wx** Mon Nov 24, 2014 11:38 am

aiannone wrote:And the CRAS says 60'S AND RAIN FOR ALL!!!!!

Why does this model still run?

by Sharon L Mon Nov 24, 2014 11:40 am

I'm just glad we still have a full winter ahead for all our debauchery and fun!

by **Frank_Wx** Mon Nov 24, 2014 11:41 am

Sharon L wrote:I'm just glad we still have a full winter ahead for all our debauchery and fun!

Me too! It is not even Meteorological winter. This is all an appetizer of what is to come.

by Sharon L Mon Nov 24, 2014 11:42 am

Mmmmm appetizers, turkey! Wine!

by **aiannone** Mon Nov 24, 2014 11:44 am

Frank, mets are saying as long as the 0c line is south of your area, heavy precip rates combined with a strengthening low near the coast will cool the column enough for snow.

by **algae888** Mon Nov 24, 2014 11:46 am

frank why does the cmc have the 540 line near buffalo and the gfs in n/new jersey?

by **Frank_Wx** Mon Nov 24, 2014 11:46 am

aiannone wrote:Frank, mets are saying as long as the 0c line is south of your area, heavy precip rates combined with a strengthening low near the coast will cool the column enough for snow.

But what mechanism is going to drive the storm to deepen? I do not see one. Unless models change the upper air pattern in 24 hours.

by **Quietace** Mon Nov 24, 2014 11:49 am

aiannone wrote:Frank, mets are saying as long as the 0c line is south of your area, heavy precip rates combined with a strengthening low near the coast will cool the column enough for snow.

As long as you have a strengthening low. Nam and GFS its not really sub 1000mb, and precip rates are not that heavy to over come high 30s Surface along the coast with a NE wind and 50 degree ocean.

by **rb924119** Mon Nov 24, 2014 11:49 am

GFS Ensembles are rolling......

by **Frank_Wx** Mon Nov 24, 2014 11:50 am

Quietace wrote:
aiannone wrote:Frank, mets are saying as long as the 0c line is south of your area, heavy precip rates combined with a strengthening low near the coast will cool the column enough for snow.
As long as you have a strengthening low. Nam and GFS its not really sub 1000mb, and precip rates are not that heavy to over come high 30s Surface along the coast with a NE wind and 50 degree ocean.

This.

by **jmanley32** Mon Nov 24, 2014 11:50 am

Alex you mentioned that yesterday, thats interesting. Frank do you think there is anything to that? With all due respect our future meterologist Alex of course : )

by **Frank_Wx** Mon Nov 24, 2014 11:51 am

RB and SNOW MAN are going to cash in (again). CP and Doc up in southern NY may do well too. I gotta go, will release a full forecast in mid afternoon. Ciao

by **rb924119** Mon Nov 24, 2014 11:51 am

Ensemble mean is west of 00z.

by **rb924119** Mon Nov 24, 2014 11:51 am

Cheers Frank!! Definitely stronger than 00z too

by **Frank_Wx** Mon Nov 24, 2014 11:52 am

rb924119 wrote:Ensemble mean is west of 00z.

Does not look like it. Also still weak

11/26 Strong Coastal Storm Possible - Page 21 GFS-ENS_MSLPThickQPF_ne_f60

Good for your area, though.

by **rb924119** Mon Nov 24, 2014 11:57 am

It's not strong by any means, but it is stronger than 00z by 4mb when it's off of the carolinas....

by **Snow88** Mon Nov 24, 2014 12:04 pm

All of the models except Ukie is on the benchmark.

by **RJB8525** Mon Nov 24, 2014 12:05 pm

Mr good ole Bill Evans has 3-6 for northern NJ highest amounts with be north west NJ dont remember exact amounts for them but he had north NJ a good swath 3-6

by **sroc4** Mon Nov 24, 2014 12:11 pm

Here is what I am talking about Frank on the GFS.
11/26 Strong Coastal Storm Possible - Page 21 <a href=

11/26 Strong Coastal Storm Possible - Page 21 Gfs_pr10

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With this system there are two sources of cold air to drive out the warmth in the mid layers. First is the HP over top. Certainly less than ideal positioning with its center but is is clearly building east over the GL and N of Maine. Second would be for the storm to generate its own cold air via evaporative cooling. Frank if the GFS is right, and that is a big if, and the jet streak is positioned here at this time frame with respect to the coastal LP center the convective banding should set up somwhere in the area I have circled in blue. The CCB is going to be a real wild card and could make or break alot of forecasts along the immediate coast IMHO. As per the GFS verbatim the streak seems strong enough to positioned such that it can overcome marginal HP positioning to the north to bring some accumulation to the coastal sections. Again going to need to study what the SR models do with the LP track as well as the streak (how strong and where the R entrance is). Still have to see what the euro does
11/26 Strong Coastal Storm Possible - Page 21 <a href=

11/26 Strong Coastal Storm Possible - Page 21 Gfs_uv10

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by **sroc4** Mon Nov 24, 2014 12:16 pm

Im not sure the strength of storm plays a huge factor. Like Rb has been preaching there appears to be strong frontogenesis with this system that sets up based on the J/S

by **algae888** Mon Nov 24, 2014 12:22 pm

jman we are the dividing line

11/26 Strong Coastal Storm Possible - Page 21 I_nw_g1_EST_2014112412_052

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