HECS Checklist.....What to Look for to Avoid

[40/70 Benchmark]

In a system as such the CF was pretty much confined to an area between plymouth and newton se to ne. We could have really saw heavy snow anywhere between there depending on how far the warm air pushed. Unfortunately I think Ray realized early on his was out of the game for the CF but did not expect everything else to **** the bed so violently. He got into the band at times, but could have easily seen 3-6" more additional if things weren't so ****ty outside of the CF.

Actually, I realized that, as well......at one point, I made a post something to the effect of "remember I said this, that band to the west is just going to rot over them and be nothing but snow showers by the time it reaches us".

Tip and I were all over that, while others were claiming that we were "giving up way too soon".

I often overreact, but not in that case.

[40/70 Benchmark]

I should probably re-phrase that other post... what I meant was this storm was a bust all-around... and are we talking about the what busted in BOX's CWA or can we include GYX's and BTV's? For some it was a bad bust, for others it was a good bust. Those folks on that NW fringe that weren't in the blizzard warning, probably saw equally bad, if not worse conditions than a lot of the blizzard warning area... that two or three county wide ribbon of 15-30" of wind-blown snow that spread along the entire NW edge of the storm probably witnessed conditions worse than some areas within the blizzard warnings (that's a bust, but in the good way for some folks if you like snow). I'm sure I-93 and I-89 in NH/VT was just brutal overnight with 2-3"/hr snows in 40-50mph winds... especially when they were only expecting 5-10" or 6-12" of snow, lol.

This will likely go down as one of the worst modeled storms in recent history, as Tippy said.

Any mets have a desire to do a case study?

I hope so.

This thread was intended to be all encompassing, btw....

[40/70 Benchmark]

I should probably re-phrase that other post... what I meant was this storm was a bust all-around... and are we talking about the what busted in BOX's CWA or can we include GYX's and BTV's? For some it was a bad bust, for others it was a good bust. Those folks on that NW fringe that weren't in the blizzard warning, probably saw equally bad, if not worse conditions than a lot of the blizzard warning area... that two or three county wide ribbon of 15-30" of wind-blown snow that spread along the entire NW edge of the storm probably witnessed conditions worse than some areas within the blizzard warnings (that's a bust, but in the good way for some folks if you like snow). I'm sure I-93 and I-89 in NH/VT was just brutal overnight with 2-3"/hr snows in 40-50mph winds... especially when they were only expecting 5-10" or 6-12" of snow, lol.

This will likely go down as one of the worst modeled storms in recent history, as Tippy said.

Any mets have a desire to do a case study?

I thought it was actually modeled pretty well, over the majority of SNE.....like that "v" shaped FU in central areas, bounded by the deformation band to the west and cf enhanced region to the east.

[ORH_wxman]

I thought it was actually modeled pretty well, over the majority of SNE.....like that "v" shaped FU in central areas, bounded by the deformation band to the west and cf enhanced region to the east.

Yeah it was fairly well modeled here in the short term...medium range disaster is a different story.

It definitely had the CT River Valley screwzone and the qpf max near BOS with more MECS-like totals in between. I think the overall amounts were a bit too high in the non-maximum areas, but it did ok overall. On the very periphery, yeah I'm sure it was a lot worse since they weren't supposed to get nearly as much and they snuck into the band from hell. But that happens very frequently in rapidly deepening storms....there is always a band that destroys a narrow area so its a bust in the positive direction for them.

[TalcottWx]

I thought it was actually modeled pretty well, over the majority of SNE.....like that "v" shaped FU in central areas, bounded by the deformation band to the west and cf enhanced region to the east.

Was it the NMM that PERFECTLY modeled the jackpot in ema before the storm started? It was almost perfect.

[Ginx snewx]

My thoughts are soley based on one theory, dry air rounded the trough and fooled with dynamics. The same setup without the massive dry air intrusion yields uniformly high 18 plus amounts with mega amounts in banded.CF areas. The snow grains are not usual in such a convective storm. In fact there were reports in the Whites of a period of grains, did not affect their totals. Summed up dry air.

[40/70 Benchmark]

Yeah it was fairly well modeled here in the short term...medium range disaster is a different story.

It definitely had the CT River Valley screwzone and the qpf max near BOS with more MECS-like totals in between. I think the overall amounts were a bit too high in the non-maximum areas, but it did ok overall. On the very periphery, yeah I'm sure it was a lot worse since they weren't supposed to get nearly as much and they snuck into the band from hell. But that happens very frequently in rapidly deepening storms....there is always a band that destroys a narrow area so its a bust in the positive direction for them.

Yup.

[radarman]

Great thread.

To get an HECS for the valley I'd rather not see the system close off at h5 at all. Gimme a stalled front funneling moisture continuously out of the due south, and a surface high partying on St. Catherine's. Low winds keep the dendrites shapely and the snow measurable. Might flirt with ZR or a little rain at the end. Wind up upsloping slightly on the trek from New Haven.

As far as the bombs go, totally agree about the ML low track. Radar will use any excuse it can to put a hole over us. I do normally like the surface low to back in to the benchmark some, as it keeps winds mostly between 320-40 degrees, but because of that mid-level track, the high winds, and not-ideal ratios, it just didn't work out for us this time.

[ORH_wxman]

Great thread.

To get an HECS for the valley I'd rather not see the system close off at h5 at all. Gimme a stalled front funneling moisture continuously out of the due south, and a surface high partying on St. Catherine's. Low winds keep the dendrites shapely and the snow measurable. Might flirt with ZR or a little rain at the end. Wind up upsloping slightly on the trek from New Haven.

As far as the bombs go, totally agree about the ML low track. Radar will use any excuse it can to put a hole over us. I do normally like the surface low to back in slightly to the benchmark, as it keeps winds mostly between 320-40 degrees, but because of that mid-level track, the high winds, and not-ideal ratios, it just didn't work out for us this time.

Oh, you definitely want 5h to close off, there aren't many HECS ever that hit us without a closed 5h low. We just don't want to see it close off too soon and have most of the dynamics get shot to the SW of us and be a bit weaker by the time they reach us which is essentially what happened in this system. Obviously this was still a pretty big snowstorm for a large chunk of SNE, but to get those monster amounts, you need the best dynamics, and they never got here as we first thought they might.

Miller A storms are tedious for us because 5h often closes off too early and we rarely jackpot in those storms. Of all the SNE HECS, the majority are Miller Bs like Jan 2005, April '97, April '82, Feb '78, March '60.

Occasionally we can get HECS totals on Miller A storms like PDII and Jan '96 (for SE areas anyway)...but its generally tougher.

[TalcottWx]

Oh, you definitely want 5h to close off, there aren't many HECS ever that hit us without a closed 5h low. We just don't want to see it close off too soon and have most of the dynamics get shot to the SW of us and be a bit weaker by the time they reach us which is essentially what happened in this system. Obviously this was still a pretty big snowstorm for a large chunk of SNE, but to get those monster amounts, you need the best dynamics, and they never got here as we first thought they might.

Miller A storms are tedious for us because 5h often closes off too early and we rarely jackpot in those storms. Of all the SNE HECS, the majority are Miller Bs like Jan 2005, April '97, April '82, Feb '78, March '60.

Occasionally we can get HECS totals on Miller A storms like PDII and Jan '96 (for SE areas anyway)...but its generally tougher.

RE snow growth; it was pretty fantastic here throughout the storm even with the high winds. Beautiful dendrites!!

[powderfreak]

Great thread.

To get an HECS for the valley I'd rather not see the system close off at h5 at all. Gimme a stalled front funneling moisture continuously out of the due south, and a surface high partying on St. Catherine's. Low winds keep the dendrites shapely and the snow measurable. Might flirt with ZR or a little rain at the end. Wind up upsloping slightly on the trek from New Haven.

As far as the bombs go, totally agree about the ML low track. Radar will use any excuse it can to put a hole over us. I do normally like the surface low to back in to the benchmark some, as it keeps winds mostly between 320-40 degrees, but because of that mid-level track, the high winds, and not-ideal ratios, it just didn't work out for us this time.

Does the CT Valley ever see a funneling low-level convergence enhancement like the Champlain Valley and Hudson Valley can on a more northerly wind flow? I feel like the CT Valley gets screwed more often than both the Champlain and Hudson valleys though it has about the same orientation. Also, the CT River Valley has smaller terrain on either side of it relative to both the Hudson and Champlain valleys, so why would it seem to get downsloped and screwed more often than the other two? I mean, the Hudson has the Catskills with peaks above 3,500ft on the west and the Berkshires with 2-3K foot terrain on the east... and the Champlain has 4-5,000ft Adirondacks on one side and 4,000ft Greens on the other.

Actually I think I just answered my first question... it must be the higher terrain on either side that causes enhanced convergence on a north wind in the Hudson and Champlain valleys. But why does it seem like the CT Valley gets screwed straight out almost every storm unlike the other two valleys which can jackpot more often than people think...especially the Champlain Valley where directional and speed convergence can cause them to clean up in certain situations.

[NECT]

This was not the first HECS/SECS toleave some of us with ~6 (or less) while other parts of NE got hammered. The Berkshires, NW CT, and NNE mountains average much more than other places in NE - there's probably a reason for that, not just latitude and elevation.

[Ginx snewx]

Does the CT Valley ever see a funneling low-level convergence enhancement like the Champlain Valley and Hudson Valley can on a more northerly wind flow? I feel like the CT Valley gets screwed more often than both the Champlain and Hudson valleys though it has about the same orientation. Also, the CT River Valley has smaller terrain on either side of it relative to both the Hudson and Champlain valleys, so why would it seem to get downsloped and screwed more often than the other two? I mean, the Hudson has the Catskills with peaks above 3,500ft on the west and the Berkshires with 2-3K foot terrain on the east... and the Champlain has 4-5,000ft Adirondacks on one side and 4,000ft Greens on the other.

Actually I think I just answered my first question... it must be the higher terrain on either side that causes enhanced convergence on a north wind in the Hudson and Champlain valleys. But why does it seem like the CT Valley gets screwed straight out almost every storm unlike the other two valleys which can jackpot more often than people think...especially the Champlain Valley where directional and speed convergence can cause them to clean up in certain situations.

BDL has gotten screwed lately but it does average quite a bit, Feb 06 LLC

[TalcottWx]

This was not the first HECS/SECS toleave some of us with ~6 (or less) while other parts of NE got hammered. The Berkshires, NW CT, and NNE mountains average much more than other places in NE - there's probably a reason for that, not just latitude and elevation.

It does always seem like Kevin gets stuck at 14"

[NECT]

It does always seem like Kevin gets stuck at 14"

I would have loved to see 14" out of this one - bet Rev. would too.

[Damage In Tolland]

I would have loved to see 14" out of this one - bet Rev. would too.

How did you get less than 6? I saw Ashford only had 5...That is awful..What a screwjob

[dendrite]

Well, there was a respectable arm of hp to the N, extending from the MW......had that not been there, I probably would have gotten dumped on, but rained for a bit.

Would have been a net gain, though.....taint likely would have made it to near rt 495.

The low deepening so rapidly also accentuated the AG flow a bit, I think because it tightened the whole circulation and caused our wind direction to have a bit more n component than it may have otherwise had.

It's called an isallobaric wind. I won't get into the calculus behind it, but those contours on maps showing 3hr pressure changes are called isallobars. Basically this wind blows across isallobars from a center of greatest pressure rises to the center of greatest pressure falls. With the low tremendously bombing out due south of us and then moving due north, it kept this component of the wind much stronger than normal out of the north.

[TalcottWx]

This was my favorite blowing and drifting storm overall. This is one of the reasons why.

[NECT]

How did you get less than 6? I saw Ashford only had 5...That is awful..What a screwjob

How? I'm just a few miles from Ashford. I don;t know how, just that I may have closer to 4 than 5.

[Ginx snewx]

This was my favorite blowing and drifting storm overall. This is one of the reasons why.

Put this in the derailed drift thread. I was starting to think none of you guys owned a camera, few pics from the jackpot windy spots.

[TalcottWx]

Put this in the derailed drift thread. I was starting to think none of you guys owned a camera, few pics from the jackpot windy spots.

Already did! I have pics in one of the midstorm threads. I'll find and repost inside of the drift thread.

[cpickett79]

Yeah it was fairly well modeled here in the short term...medium range disaster is a different story.

It definitely had the CT River Valley screwzone and the qpf max near BOS with more MECS-like totals in between. I think the overall amounts were a bit too high in the non-maximum areas, but it did ok overall.

yes it just had the QPF max extendng over into andover and wilmington (at least i saw a couple late runs of the nam that really JPotted the area) but alas it never happened.

QPF was actually much lower then forecast (i.e 30%+) i believe for everyone outside of the NW DEFORM BAND and The area that received the heavy wet snows (i.e brockton SSW toward taunton)

i mean what did ORH have melted down .50 ? and BDL .25 ......KTAN Had close to 2.0. as did most of central /eastern bristol country and western plymouth country nosing intoward S. suffolk. (blue hills area)

[dendrite]

Another key : Someone mentioned it went warm core as it passed to our south... with the low passing so close to us and with warmer air aloft then in a cold core system, that would have a dramatic effect on the system, no?

It had a warm core seclusion which is common of the deep Atlantic lows. I'm really hesitant to believe that CT had an above 0C layer in the column leading to sleet. I think the issue had to do with poor nucleation for growing snow crystals. I think I remember Gibbs posting an OKX sounding showing poor 700mb temps for nucleation and the dry air aloft didn't help either. As a result the snow growth was very poor and people were getting snow grains. The 1/4" diameter snow pellets that we even had up into C NH were caused by riming. So instead of getting the crystals to grow by deposition and getting actual snow "flakes" we were getting heavily rimed crystals. So although it was a relatively warm layer that ruined nucleation it wasn't necessarily a >0C layer. I think the only legit sleet was in SE MA where that warm nose snuck in aloft.

And btw Ray...good thread.

[Ginx snewx]

How did you get less than 6? I saw Ashford only had 5...That is awful..What a screwjob

But at least we have no bare spots.

[Ginx snewx]

Already did! I have pics in one of the midstorm threads. I'll find and repost inside of the drift thread.

Awesome

[cpickett79]

Miller A storms are tedious for us because 5h often closes off too early and we rarely jackpot in those storms. Of all the SNE HECS, the majority are Miller Bs like Jan 2005, April '97, April '82, Feb '78, March '60.

Occasionally we can get HECS totals on Miller A storms like PDII and Jan '96 (for SE areas anyway)...but its generally tougher.

MAR 93......was a miller A and that gave stoneham 18 worcester 20 somethin right?

DEC 92 was what miller B?

[#NoPoles]

MAR 93......was a miller A and that gave stoneham 18 worcester 20 somethin right?

DEC 92 was what miller B?

where i live, not a fan of miller A's...93 we got a foot and then went over to sleet...never get the good snow totals out of miller A's...

[ORH_wxman]

MAR 93......was a miller A and that gave stoneham 18 worcester 20 somethin right?

DEC 92 was what miller B?

Mar '93 gave us 20" but we didn't jackpot. The jackpot was closer to 100-200 miles W of here in NY State and back through central PA where widespread 30"+ totals happened. It was such a massive storm that we got 20" basically from its insane WCB.

Dec '92 was basically a bowling ball Miller B...very juicy system out of the TN/OH Valley.

[TalcottWx]

Awesome

Found em, posted.

[cpickett79]

pretty good link here on set ups' enso state's NAO orientation etc.....for a number of storms that slammed us ....some are left out (dec 92) as this is ranked according to SE Pa's big snow totals but it's a good read

http://berkswintercast.tripod.com/id85.html