How common a warning criteria snow event is in SNE after March 7th

[ORH_wxman]

I am stealing this thread from Eastern that I made back in 2007 to give people a general sense for climo on snow after March 7th...the first week of March is heavily more favored than the final 3 weeks, so that is not included...we have a long way to go until we get to March 7th, but if we get there without much snow at all, here is what the prospects look like for a big storm.

As we wait for anything else to track and the fact I am bored this Saturday...I decided to look up how common "big snow events" are in Southern New England after March 7th since it looks like we will go the first week without anything major.

I have defined "big" at anything 7.0"+...using warning criteria snow. Sure we get plenty of 3"+ events, but nobody cares about those really, they are more of a nuisance in latter March that melt very quickly...I personally don't they are worth the trouble.

Okay so the number crunching begins. Last 10 storms that meet the above criteria for date and snowfall.

BOS:

March 16-17, 2007.........8.1"

March 16-17, 2004........ 9.6"

March 31-Apr 1, 1997.. 25.4"

March 7-9, 1996...........10.5"

March 13-14, 1993........12.8"

March 24, 1993..............8.5"

March 29-30, 1984.........9.4" (6.7" on March 13, 1984)

April 6-7, 1982..............13.3"

March 18-19, 1977..........9.6"

March 29, 1970...............7.3"

March 15-16, 1967.........10.0"

ORH:

March 16-17, 2007.........16.9"

March 12, 2005...............9.7"

March 20, 2002...............7.0"

March 31- Apr 1, 1997....33.0"

April 9-10, 1996.............16.0"

March 7-9, 1996.............11.5"

March 13-14, 1993..........20.1"

April 28-29, 1987............17.0"

March 13-14, 1984...........8.4"

March 29-30, 1984..........17.6"

April 6-7, 1982................15.1"

PVD:

March 14-15, 1999............8.7"

March 31- Apr 1, 1997......19.5"

March 7-9, 1996................8.5"

March 13-14, 1993...........10.2"

April 6-7, 1982..................7.6"

March 29-30, 1984............7.8"

March 16-17, 1978............9.1"

March 9-10, 1976..............7.0"

March 29, 1970.................7.8"

March 15-16, 1967............11.1"

BDL:

March 16-17, 2007...............10.2"

Mar 31- Ap1 1, 1997............16.0" (est)

April 9-10, 1996....................7.0"

March 7-9, 1996..................11.5"

March 13-14, 1993...............14.8"

March 14-15, 1984.................8.9"

April 6-7, 1982.....................14.1"

March 18, 1977......................7.4"

March 16, 1976......................7.1"

March 14-15, 1972...............10.1"

March 29, 1970......................7.0"

Boston had 10 times in the past 40 years...25% of the time, PVD had 11 times adding the 2nd event in March 1967 that was not on the list since I only listed the 10 most recent ones, but PVD recorded 9.2" on March 22, 1967. ORH 10 times in the past 25 years for 40%. Looking further back to 1967 for ORH yields 9 more for a total 19 in 40 years and 47.5%. There were quite a few 5-6 inch events at both stations that did not make the list but would probably prove to be a decent event and impact for most. The late 1950s were very good for both stations for late storms after March 7th that are not included in the numbers since I had to make a cutoff at some date otherwise it would take me forever.

I havent looked at BDL/PVD yet, I'll try to add them later on tonight. If any numbers are wrong, it might be more recent in the past 5 years, but I think I covered all of the events at/over 7.0" past the 7th.

Latest date for each station that met above criteria: (at least since 1948)

BOS: April 6-7, 1982.....13.3"

ORH: May 9-10, 1977....12.7"

PVD: April 6-7, 1982.......7.6"

BDL: April 6-7, 1982......14.1"

This winter has been pretty sorry, and might have a good chance to go out with a wimper...but since there are hints that the pattern may become a bit cooler and stormier for the 2nd half of the month after a warmup the 2nd week, I thought this idea should be brought up. Last year we squandered a pretty good pattern late the 3rd week of March into the 4th week.

Totals since 1967 (45 years):

BOS: 11

PVD: 11

ORH: 20

BDL: 13

No station has had a warning criteria snowfall after March 7th since 2007.

[powderfreak]

I have defined "big" at anything 7.0"+...using warning criteria snow. Sure we get plenty of 3"+ events, but nobody cares about those really, they are more of a nuisance in latter March that melt very quickly...I personally don't they are worth the trouble.

Very interesting stats, ORH. It seems its about time for one to happen and if there was ever a season to see some late year whopper, this is probably the one, haha. Bookending KUs.

However, I really do not believe the above statement coming from you I'm sure you wrote this back on Eastern from the sounds of it, but this year I'll take 3"+ events all month long after the first week of March. I have a hard time imagining you looking at ~0.5" of QPF as 9:1 paste on March 11th and saying a 3-6" event isn't worth it.

I'm just busting your ballz... nice work.

[HoarfrostHubb]

Last year I had 7" on April 1st, but ORH did not get that high

[Collinsville]

I had 8.4" on March 14-15, 1999 so there's a decent chance BDL had 7" except they weren't measuring att.

[CapturedNature]

I had 8.4" on March 14-15, 1999 so there's a decent chance BDL had 7" except they weren't measuring att.

Agreed. I had 7.4" that day so I would agree that BDL probably had a warning level event that day.

Also, what's up with the 16" estimate on March 31st-April 1st? That's actually my biggest storm in the last 28 season's with 28". I remember digging out in the valley and there was more than 16".

This exercise has peaked my interest and I may go back and see what the stats are for my location...

[Collinsville]

Also, what's up with the 16" estimate on March 31st-April 1st? That's actually my biggest storm in the last 28 season's with 28". I remember digging out in the valley and there was more than 16".

This exercise has peaked my interest and I may go back and see what the stats are for my location...

I actually think BDL measured 14.7" for that storm. I only had 16".

I took quick look at my own 15 year data and found 5 storms that met the 7" criteria

Mar 31/Apr 1, 1997 ..... 16.0"

Mar 14-15, 1999 ........... 8.4"

Mar 9-10, 2001 ............. 8.0"

Mar 23-24, 2005 ........... 7.2"

Mar 16-17, 2007 .......... 10.5"

[larvay]

Agreed. I had 7.4" that day so I would agree that BDL probably had a warning level event that day.

Also, what's up with the 16" estimate on March 31st-April 1st? That's actually my biggest storm in the last 28 season's with 28". I remember digging out in the valley and there was more than 16".

This exercise has peaked my interest and I may go back and see what the stats are for my location...

16" for 4/1/97 sounds reasonable for where I was at the time in Chicopee (my sister's house, essentially at river level). That's about what we had on the ground at the end. Of course, it was still ripping up to 10-12 hours in, so a board clearing would have yielded a couple of inches more. Still, the best storm I've witnessed, but a few hundred feet of elevation would have made a big difference. As usual.

[Typhoon Tip]

I am stealing this thread from Eastern that I made back in 2007 to give people a general sense for climo on snow after March 7th...the first week of March is heavily more favored than the final 3 weeks, so that is not included...we have a long way to go until we get to March 7th, but if we get there without much snow at all, here is what the prospects look like for a big storm.

As we wait for anything else to track and the fact I am bored this Saturday...I decided to look up how common "big snow events" are in Southern New England after March 7th since it looks like we will go the first week without anything major.

I have defined "big" at anything 7.0"+...using warning criteria snow. Sure we get plenty of 3"+ events, but nobody cares about those really, they are more of a nuisance in latter March that melt very quickly...I personally don't they are worth the trouble.

Okay so the number crunching begins. Last 10 storms that meet the above criteria for date and snowfall.

BOS:

March 16-17, 2007.........8.1"

March 16-17, 2004........ 9.6"

March 31-Apr 1, 1997.. 25.4"

March 7-9, 1996...........10.5"

March 13-14, 1993........12.8"

March 24, 1993..............8.5"

March 29-30, 1984.........9.4" (6.7" on March 13, 1984)

April 6-7, 1982..............13.3"

March 18-19, 1977..........9.6"

March 29, 1970...............7.3"

March 15-16, 1967.........10.0"

ORH:

March 16-17, 2007.........16.9"

March 12, 2005...............9.7"

March 20, 2002...............7.0"

March 31- Apr 1, 1997....33.0"

April 9-10, 1996.............14.0"

March 7-9, 1996.............11.5"

March 13-14, 1993..........20.1"

April 28-29, 1987............17.0"

March 13-14, 1984...........8.4"

March 29-30, 1984..........17.6"

April 6-7, 1982................15.1"

PVD:

March 14-15, 1999............8.7"

March 31- Apr 1, 1997......19.5"

March 7-9, 1996................8.5"

March 13-14, 1993...........10.2"

April 6-7, 1982..................7.6"

March 29-30, 1984............7.8"

March 16-17, 1978............9.1"

March 9-10, 1976..............7.0"

March 29, 1970.................7.8"

March 15-16, 1967............11.1"

BDL:

March 16-17, 2007...............10.2"

Mar 31- Ap1 1, 1997............16.0" (est)

April 9-10, 1996....................7.0"

March 7-9, 1996..................11.5"

March 13-14, 1993...............14.8"

March 14-15, 1984.................8.9"

April 6-7, 1982.....................14.1"

March 18, 1977......................7.4"

March 16, 1976......................7.1"

March 14-15, 1972...............10.1"

March 29, 1970......................7.0"

Boston had 10 times in the past 40 years...25% of the time, PVD had 11 times adding the 2nd event in March 1967 that was not on the list since I only listed the 10 most recent ones, but PVD recorded 9.2" on March 22, 1967. ORH 10 times in the past 25 years for 40%. Looking further back to 1967 for ORH yields 9 more for a total 19 in 40 years and 47.5%. There were quite a few 5-6 inch events at both stations that did not make the list but would probably prove to be a decent event and impact for most. The late 1950s were very good for both stations for late storms after March 7th that are not included in the numbers since I had to make a cutoff at some date otherwise it would take me forever.

I havent looked at BDL/PVD yet, I'll try to add them later on tonight. If any numbers are wrong, it might be more recent in the past 5 years, but I think I covered all of the events at/over 7.0" past the 7th.

Latest date for each station that met above criteria: (at least since 1948)

BOS: April 6-7, 1982.....13.3"

ORH: May 9-10, 1977....12.7"

PVD: April 6-7, 1982.......7.6"

BDL: April 6-7, 1982......14.1"

This winter has been pretty sorry, and might have a good chance to go out with a wimper...but since there are hints that the pattern may become a bit cooler and stormier for the 2nd half of the month after a warmup the 2nd week, I thought this idea should be brought up. Last year we squandered a pretty good pattern late the 3rd week of March into the 4th week.

Totals since 1967 (45 years):

BOS: 11

PVD: 11

ORH: 20

BDL: 13

No station has had a warning criteria snowfall after March 7th since 2007.

It would be intereting to include the 1950s in this study. 1956 (or '57?) had an incredible March.

[mitchnick]

It would be intereting to include the 1950s in this study. 1956 (or '57?) had an incredible March.

3/58

57/58 was a mod/strong NINO

it was even great in the MA

in 2/10, there was talk of 3/10 turning out just as good up and down the coast, but it never worked out

EDIT: 3/56 was decent down here too, so maybe you were referring to 56'

[CapturedNature]

I went back through my own data and using the strict warning criteria of 6" or more in a 12 hour period, that occurred 10 out of the past 26 seasons or 34% of the time. That seems to be right between the ORH and BDL which is where I am.

Using the 7" mark mentioned above, it happened 8/28 times or 31% of the time.

One question that I had was 4/28/87. I had 4" that day but I know that several locations around me and higher up had more than that. I was wondering if warnings were issued. I remember some details of that storm but I just don't know about that. I do know that it also snowed Oct 4, 1987 which is the least number of days between the last and first snows. That led to above normal snow that season!

None since 3/2007 so we are "due". lol

[ORH_wxman]

Last year I had 7" on April 1st, but ORH did not get that high

There were several storms that had 6"+ but didn't quite make the list because I used 7" as a cutoff. I had 6.4" I think last April 1st.

[weatherwiz]

Thanks for posting this...pretty interesting. This is actually really awesome you've posted this b/c over the past several days I've been thinking, "Wouldn't it be something if we got slammed in March"? I was actually going to either PM or make a thread asking for some of the biggest March storms we have had and then look at what the 500mb pattern was like just prior to those storms and also look at how the 500mb pattern was about a month out and how the pattern(s) evolved leading up to the storms.

[N. OF PIKE]

I went back through my own data and using the strict warning criteria of 6" or more in a 12 hour period, that occurred 10 out of the past 26 seasons or 34% of the time. That seems to be right between the ORH and BDL which is where I am.

Using the 7" mark mentioned above, it happened 8/28 times or 31% of the time.

One question that I had was 4/28/87. I had 4" that day but I know that several locations around me and higher up had more than that. I was wondering if warnings were issued. I remember some details of that storm but I just don't know about that. I do know that it also snowed Oct 4, 1987 which is the least number of days between the last and first snows. That led to above normal snow that season!

None since 3/2007 so we are "due". lol

reading over this quickly these numbers 10/26 = 34% don't jive. 37.5-38% just for the sake of accuracy

i would be intersted in looking up the same stats for elevated areas in SNE....such as COOPS near 1400' of so as well as places 1-2k in CNE/NNE as well. just to see how frequent they are ...esp after mid april for elevation further north

edit ; this gives idea to my 2'nd paragraph question http://www.nws.noaa.gov/climate/xmacis.php?wfo=gyx

[ORH_wxman]

Going back further as some asked...for ORH I got these events:

3/12/59...15.8"

3/27/59...8.1"

3/14/58...14.0"

3/21/58...18.8"

4/11/58...8.5"

3/16/56...7.0"

3/19/56...7.0"

3/24/56...9.0"

4/8/56....10.2"

A couple close misses with 3/21/63 (6.6") and 3/14/61 (6.1")

But the others end up adding 9 more events in while tacking on another 11 years making it a total of 29 events in 56 years. Those late 1950s were pretty awesome for late season events.

[CapturedNature]

reading over this quickly these numbers 10/26 = 34% don't jive. 37.5-38% just for the sake of accuracy

i would be intersted in looking up the same stats for elevated areas in SNE....such as COOPS near 1400' of so as well as places 1-2k in CNE/NNE as well. just to see how frequent they are ...esp after mid april for elevation further north

edit ; this gives idea to my 2'nd paragraph question http://www.nws.noaa....cis.php?wfo=gyx

I stand corrected! I have no idea where I came up with that, but you're right, 10 ÷ 26 = 0.384 and 0.384 X 100 = 38.4%. Must have been the crazy M$ Calculator!

[tamarack]

i would be intersted in looking up the same stats for elevated areas in SNE....such as COOPS near 1400' of so as well as places 1-2k in CNE/NNE as well. just to see how frequent they are ...esp after mid april for elevation further north

edit ; this gives idea to my 2'nd paragraph question http://www.nws.noaa....cis.php?wfo=gyx

Some modest elevation (near 400') NNE data, Farmington and MBY:

Farmington (most recent 10):

4/1-2/2011...12.5"

4/12-13/2007...10.8"

4/4-5/2007...18.0"

3/16-17/2007...10.3"

3/8-9/2005...16.0"

3/20-21/2002...9.0

3/30-31/2001...18.0"

3/22-23/2001...15.0"

3/11-12/2000...7.0"

3/15-16/1999...9.0"

MBY (1998-99 on - 11 in 13 yr)

4/1-2/2011...15.1"

4/12-13/2007...11.2"

4/4-5/2007...18.5"

3/16-17/2007...8.0"

3/8-9/2005...11.5"

3/20-21/2002...9.0

3/30-31/2001...19.0"

3/22-23/2001...16.0"

3/10/2001....7.0"

3/11-12/2000...7.3"

3/15-16/1999...14.0"

[Collinsville]

I stand corrected! I have no idea where I came up with that, but you're right, 10 ÷ 26 = 0.384 and 0.384 X 100 = 38.4%. Must have been the crazy M$ Calculator!

Looks like the conclusion is that there's about a 25% to 45% (depending on elevation) chance of seeing a 7" storm after March 7th for interior Connecticut.

[BillB]

_{Record high temps at BOS fluctuate between 55 and 70 through the winter, then start getting higher in mid-March. So some date between March 7 and March 14 should be a good starting point for winter's "end game".}