Blog: February 5th Potential (Sneak Attack?)

Latest 4km NAM:

@amugs wrote:0Z UKIE!!!

WTH? WWA will be needed for NYC and EAST?

Wow! I forgot to include Ukie in my post but it too has been right in line with Euro/RGEM in consistency and higher totals west.

@amugs wrote:SROC - 4K NAm is actually in line with each of the models but has teh heavier precip trending west

Yeah its crazy. 4k NAM has 10 IMBY. It has sharp cutoffs west though. Def trending west. The 12z today should be interesting.

The differences at 500mb regarding tomorrow's system is quite different on latest modeling compared to earlier in the week.

Tuesday's 12z GFS valid 1pm Friday:



Latest GFS valid 1pm Friday:



Notice how the trough is stronger, the vorticity is more potent, and it's closer to the coast. This makes a huge difference with where the front and surface low tracks.

The RGEM seems to be leading the way with this one, as have the SREFS. The GFS caught on last night.





There is decent 700mb VV's as well to promote lift and enhanced snow rates along the coast, especially Long Island.





Right now I think this starts as a rain / mix for most with a transition to snow. Surface temps are above freezing but boundary layers are supportive of snow. I think most accumulations will be relegated to grassy surfaces. The worst of the snow will be between 5-9am on Friday. Here is what I am thinking with snow accumulations for the area.



We'll see how this plays out on today's models. There is no denying the west trend at this point.

Wow, sneak attack NJ you were right all along, just needs jog a tony bit west to get me into some good stuff but Frank ur 2-4 makes me happy, guess I gotta let my CT and RI friends know to expect 3-6+, they won't be happy not snow lovers. I hope the media talks about this right now nothing on news.

To expand a little further on what Frank mentioned regarding the GFS trend Ill show the Euro at 500mb since that was the example I used in my prev write up:  

Recall the 00z Run from Jan 31st Euro 500mb map:
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Pay particular attention to the trough being positive by 12z Friday, the wave spacing between the next system and Friday system, and the ridge in between them.

Now look at last nights Euro  500mb map valid the same Friday 12z time frame:



Three important differences.  Wave spacing between the two systems is better spread apart(second system is further west), and the the second system is deeper.  This allows the ridge in between to be more amped than the prev image above.  Pay particular attention to the height lines within the area I have circled, then look at the same area on the first map.  Models clearly had those height lines flatter and have trended steeper with time.

The wave spacing was key to allowing the ridge to trend a tad more amped, this in turn allowed the energy to consolidate at the base of the trough better for Friday which is why it tilted into the neutral position.  If you recall from the prev discussion the more the trough tilted towards neutral trough the stronger LP would be allong the frontal boundary, and a more robust moisture plume, and a NW trend to the precip shield.

@sroc4 wrote:

@amugs wrote:0Z UKIE!!!

WTH? WWA will be needed for NYC and EAST?

Wow! I forgot to include Ukie in my post but it too has been right in line with Euro/RGEM in consistency and higher totals west.  

Wow RI to cape cod how much is that like a foot?

Wow