USCAPEWEATHERAF

Just made up drama that does not need to occur!

What is everyone looking at with the GEFS mean? While yes the mean might be southeast, but the bend and anomaly is to the northwest, the bend is to the northwest where most members are located, not southeast. Might have a few members that are strong and skew the mean to the southeast, but that does not mean the majority of members agree on a southeast tug, they are more northwest!

Precip should not be something you hammer on at this point, watch track and H5 adjustments!

I know the NAVGEM is rarely used these days due to being outdated and not really high resolution fields anymore, but it does have a progressive tone to its forecasting and we were told to have a red flag to the progressive side of the solutions envelope whenever the model was more amped and further northwest. Well the 18z NAVGEM was just as similar to the 84 hour NAM.

00z GEFS mean is actually more west and northwest than the operational. Also the individual members are more west and northwest of the mean with more members than previous runs, they also prolong the precipitation more from hours 78 to 96.

I am never sold on the GFS during a progressive like season in the LA Nina driven northern branch with its heavy biases towards progressive patterns. Will or anyone who has been paying attention, does the new GFS have the biases the old GFS did with the progressive tendencies, I found that the previous GFS had a tendency to be quite progressive over the East Coast prior to storms. Within the 3-7 day window!

We have seen models do this cat and mouse dance numerous times before in the big storms. For the 3-4 day window where the storm might be tracking too far southeast for any meaning full impacts, the models would have a tendency to first under sell the intensity of the energy moving onshore the western CONUS and also losing the organization of the trough as it heads stateside across the plains. However, within 48 hours, the trend would be for a better sampling, and a better consolidated piece of energy. If I am not mistaken once such occurrence was the FEB 2016 SNOWICANE that missed by 100 miles, but the H5 and H7 circulations were large enough, it brought almost a foot of snow to the SE New England areas, especially BOS SE.

Actually the H5 shortwave and long wave trough look a lot healthier through 61 hours on the 00z GFS. In fact the southern energy that rounds the base of the long wave trough is more neutral tilted almost leaning negative as the main shortwave leans negative. Overall there is more pure balance to the long wave trough. Better organization leads to a better storm overall.

yeah

I honestly can see how it would rain with the storm tracking just south of Islip by like 50-100 miles. That brings in a strong southeasterly low level flow into the coast. Our surface high would not be strong enough to keep the cold air locked in with a southeast wind!

Oh and also the NAM is still south of central LI with the surface low at 84 hours, which means it is still producing snow over the region and any rain changed back to snow!

00z NAM would produce rain for the Cape!

Oh, just a short term nowcast bit of information, the storm over MS and the Southeast US is more amplified than modeled.

NAM closes off the H5 trough at 84 hours. That is why the low is so far north but the surface low does not intensify much at all!

18z EURO shows us how we can get a KU out of this synoptic scale pattern

I hate Ray's map, because I am biased to the Cape. However, overall it looks in line with the latest guidance, except for the GFS

For me the last two plus winters!

I agree Ray, as long as the lift is right in the DG zone at the time of strongest lift (-12 to -18C) zone for a good 12 hours, it does not matter how long the duration is of light snow!

The clear signal on the model as a consensus is that there will be intense lift in the DG zone for a bit, and the SSTs are quite warm combined with 850mb temps near -10 to -12C, we are talking about a tremendous moisture feed from the northeast. The ocean enhancement cannot be ignored with this system. The models will begin to show this impact within 24 hours of the onset of the snow, which is 72 hours from 00z tonight!

Its not happening even with that track!

I thought that was this morning's

Thanks! Yeah before my lifetime, Cape Cod was a winter refuge. During my lifetime, since High School started, we have had some monsters, the JAN 05 Blizzard, the JAN 15 Blizzard, FEB 2013 Blizzard, JAN 2016 Blizzard, the FEB 2015 Blizzard, the DEC 2010 storm, and others!

The graphics has Chatham with 10.5 inches for WED/THU already!

Honestly, we will not know the future outcomes with more than 50/50 certainty until 12z runs tomorrow as a winter storm approaches the region!

Parts of west/central Maryland and Pennsylvania see upwards of 24" of snow on the 18z NAM through 84 hours.