******OK SINCE I GOT SOME REQUESTS FOR AN ANALYSIS OF THE STORM HERE IT IS FOR ANYBODY WHO WANTS TO UNDERSTAND WHAT HAPPENED. IF YOU ARE CONFUSED JUST ASK*******
FIRST OFF - I am seeing some articles saying that favoring one model was the main reason for this forecast bust. Sorry folks, but there were other reasons, outlined below that EVERYBODY missed - not just the models. We cannot blame computers for everything!
STORM HISTORY: The Storm formed further to the SW than originally thought and what was shown on the models, just to the east of South Carolina and with a more negative tilted trough axis. I think this led many to believe (including Dillon and I) that this would cause it to hug the coast more as it came up and then deepen and strengthen a bit sooner so that by the time it got up to LI it would stall and send those strong snows for a longer period of time. We should have seen this a bit on the Euro, as it hinted in the 12z model run on Monday that there would be a 30+" band over NYC through Central CT. If the storm had gone according to plan this would have been quite possible.
The storm Storm moved East of Hatteras, NC but further West then models saw and that is when got those initial bands of heavy snow in the afternoon over LI and Southern CT and Westchester, part of NJ and PA as the clipper finished transferring its energy over to the developing storm.
The storm moved up as planned, stalled as planned blah blah.
So where did we get caught?
WHAT HAPPENED - First off, the Boundary between the Arctic air bleeding off the HP and the warmer air boundary was where it should have been the whole time, as shown on the models and upper air progs/surface maps and satellite, and the storm DID form along it as it should have. This made me believe even more it would follow a more westerly track as that’s where it would form and the Boundary was over NY.
Once the storm got SE of LI though I noticed on the upper air progs we ran into trouble. All the models I think (that were printing out 24+” snow) were assuming this storm would:
(1) close off the trough at 700mb and then that would enable the heaviest snows to be focus N/NW of the low track (hence why I thought those bands S of Boston would move West) This storm SHOULD HAVE this by 6-8pm in order for anybody WEST of NY/CT Border to get the big snows.
(2) The trough at 500mb did not close nearly in time, which should have been after midnight so that the storm would slow down and stall more throwing back more snow. It EVENTUALLY did this Early Tuesday morning (When we got that band of snow this morning).
(3) The trough (dip in the jet stream) was SO inverted even when it got up here that it allowed a ton of air to sink over into it over PA and around me over NY/CT border. This PROBABLY contributed to the precipitation being “dried” out of the storm on the WESTERN SIDE of the Precipitation shield as all this air rose and then had to sink elsewhere. If anybody was watching the radar at the time, it looked like a wall of snow JUST to the east of NYC and it was barely moving west, or looked like it was being eaten/squished up East of the Hudson.
(4) The rising warmer air and the sinking colder air around us PROBABLY contributed to more condensation which led to more latent heat and then the clouds just keep on floating up like balloons. (Clouds warmer then air around them)
SO TO SUM IT ALL UP: The precipitation shield was just being eaten away as it came farther west, and then that combined with the sudden track trend east at like 2am led to the precipitation being lost over us. The low became to progressive and then got captured too late for us folks east of CT. Looks like NYC got a decent band late at night, and LI just kept getting pounded as the ocean probably helped with setting up those extreme bands of snow. In fact, another thing interested about the inverted trough – usually don’t see that sort of mesoscale extreme weather in winter…but hey Mother Nature does what mother nature wants.
WHAT COULD WE HAVE DONE BETTER:
1 - In the future, we will now look at, in much more detail the realtime data, IE Radar, Satellite, Water Vapor loops and upper air progs so that we can see what the storm is actually doing instead of what the model wants it to do.
2 - Do not lean towards/favor one model - pay more attention to trends on other models and combine them into our forecasts.
3- Look for the tiniest details, because they can be the biggest game changers!
This storm was always "TOO GOOD" to be true. It is amazing how PERFECTLY the variables have to add up to get a storm like this. One little thing can change everything.
HAVE A GOOD NIGHT FOLKS, THANKS FOR LISTENING, AND IF YOU HAVE ANY QUESTIONS - ASK!
FIRST OFF - I am seeing some articles saying that favoring one model was the main reason for this forecast bust. Sorry folks, but there were other reasons, outlined below that EVERYBODY missed - not just the models. We cannot blame computers for everything!
STORM HISTORY: The Storm formed further to the SW than originally thought and what was shown on the models, just to the east of South Carolina and with a more negative tilted trough axis. I think this led many to believe (including Dillon and I) that this would cause it to hug the coast more as it came up and then deepen and strengthen a bit sooner so that by the time it got up to LI it would stall and send those strong snows for a longer period of time. We should have seen this a bit on the Euro, as it hinted in the 12z model run on Monday that there would be a 30+" band over NYC through Central CT. If the storm had gone according to plan this would have been quite possible.
The storm Storm moved East of Hatteras, NC but further West then models saw and that is when got those initial bands of heavy snow in the afternoon over LI and Southern CT and Westchester, part of NJ and PA as the clipper finished transferring its energy over to the developing storm.
The storm moved up as planned, stalled as planned blah blah.
So where did we get caught?
WHAT HAPPENED - First off, the Boundary between the Arctic air bleeding off the HP and the warmer air boundary was where it should have been the whole time, as shown on the models and upper air progs/surface maps and satellite, and the storm DID form along it as it should have. This made me believe even more it would follow a more westerly track as that’s where it would form and the Boundary was over NY.
Once the storm got SE of LI though I noticed on the upper air progs we ran into trouble. All the models I think (that were printing out 24+” snow) were assuming this storm would:
(1) close off the trough at 700mb and then that would enable the heaviest snows to be focus N/NW of the low track (hence why I thought those bands S of Boston would move West) This storm SHOULD HAVE this by 6-8pm in order for anybody WEST of NY/CT Border to get the big snows.
(2) The trough at 500mb did not close nearly in time, which should have been after midnight so that the storm would slow down and stall more throwing back more snow. It EVENTUALLY did this Early Tuesday morning (When we got that band of snow this morning).
(3) The trough (dip in the jet stream) was SO inverted even when it got up here that it allowed a ton of air to sink over into it over PA and around me over NY/CT border. This PROBABLY contributed to the precipitation being “dried” out of the storm on the WESTERN SIDE of the Precipitation shield as all this air rose and then had to sink elsewhere. If anybody was watching the radar at the time, it looked like a wall of snow JUST to the east of NYC and it was barely moving west, or looked like it was being eaten/squished up East of the Hudson.
(4) The rising warmer air and the sinking colder air around us PROBABLY contributed to more condensation which led to more latent heat and then the clouds just keep on floating up like balloons. (Clouds warmer then air around them)
SO TO SUM IT ALL UP: The precipitation shield was just being eaten away as it came farther west, and then that combined with the sudden track trend east at like 2am led to the precipitation being lost over us. The low became to progressive and then got captured too late for us folks east of CT. Looks like NYC got a decent band late at night, and LI just kept getting pounded as the ocean probably helped with setting up those extreme bands of snow. In fact, another thing interested about the inverted trough – usually don’t see that sort of mesoscale extreme weather in winter…but hey Mother Nature does what mother nature wants.
WHAT COULD WE HAVE DONE BETTER:
1 - In the future, we will now look at, in much more detail the realtime data, IE Radar, Satellite, Water Vapor loops and upper air progs so that we can see what the storm is actually doing instead of what the model wants it to do.
2 - Do not lean towards/favor one model - pay more attention to trends on other models and combine them into our forecasts.
3- Look for the tiniest details, because they can be the biggest game changers!
This storm was always "TOO GOOD" to be true. It is amazing how PERFECTLY the variables have to add up to get a storm like this. One little thing can change everything.
HAVE A GOOD NIGHT FOLKS, THANKS FOR LISTENING, AND IF YOU HAVE ANY QUESTIONS - ASK!
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