March 31st - Potential Wintry Precip (formerly the March Torch Thread)

[bluewave]

The warmest temperatures should come later on toward the end of the 6-10 day range as the trough is forecast

to drop in o the West and really pump the ridge in the East. That's when we will probably have a good shot

at 80's for the warmest spots.

[Isotherm]

Early warmth = early start to severe season? I know in a patter that is dominated by a SE ridge thats not likely to happen, but perhaps if a strong enough low tracked to our west we could get a few strong cold fronts.

Getting severe wx up here is much more difficult in the early/mid spring than is in Sept or even Oct - part of that is due to the colder ocean. Strong convection feeds off of warm/moist low levels, and most of the time, dew points are not sufficient to maintain intense T-storm action in March/April. Inversions often in place, but we can have some decent elevated convection in the spring. From my experience, severe threats during the Mar-Apr period are usually a bust in the Northeast, although there are exceptions. I recall a couple of interesting synoptics in late March w/ a strong sfc warm front setting off multicellular to even supercellular type convection. I forget what year this was - several years ago at least.

[Isotherm]

The warmest temperatures should come later on toward the end of the 6-10 day range as the trough is forecast

to drop in o the West and really pump the ridge in the East. That's when we will probably have a good shot

at 80's for the warmest spots.

Strongly agree, sun dresses will be out in full force early next week.

[bluewave]

Strongly agree, sun dresses will be out in full force early next week.

Yeah, I am thinking that we will be able to pull ahead of March 2010 for monthly average temperature.

We'll have to see how long the pattern persists after the 20th or so to know how close to the top we

can get.

[nycsnow]

It looks to be fairly dry for a while to

[tornadojay]

Getting severe wx up here is much more difficult in the early/mid spring than is in Sept or even Oct - part of that is due to the colder ocean. Strong convection feeds off of warm/moist low levels, and most of the time, dew points are not sufficient to maintain intense T-storm action in March/April. Inversions often in place, but we can have some decent elevated convection in the spring. From my experience, severe threats during the Mar-Apr period are usually a bust in the Northeast, although there are exceptions. I recall a couple of interesting synoptics in late March w/ a strong sfc warm front setting off multicellular to even supercellular type convection. I forget what year this was - several years ago at least.

yea, we seem to do pretty good with severe wx when there are warm fronts involved

[forkyfork]

The euro is weak with the wednesday front... Back into the 70s next thursday

[earthlight]

The Euro has the BDCF on Wednesday at first glance...but it has 70 F temps through the end of the run after that

[earthlight]

The euro is weak with the wednesday front... Back into the 70s next thursday

It's still there though...temp goes from ~60 to 40's in NYC from 18z to 00z Wed-Thu.

But beyond that it's in the 70's every day.

[earthlight]

yea, we seem to do pretty good with severe wx when there are warm fronts involved

Severe weather in this area is pretty frustrating. Many times we'll either have the kinematic support, or the thermodynamic support..but most times we won't be able to juxtapose them at the right time. How many Moderate Risks have we seen from SPC with 6,000 kts of 0-6km bulk shear and tons of low level shear...with 50 joules of cape? In the summer, we'll have thermodynamic support through the roof...but the mid level shear is so weak that we need to start throwing rocks into the sky to break the cap.

The warm fronts provide a good chance for us because the low level shear along the front obviously aids in that department...while we can usually have some kind of instability in place as well. Most of the storms that are supercellular in nature around this area ride along warm fronts.

[forkyfork]

It's still there though...temp goes from ~60 to 40's in NYC from 18z to 00z Wed-Thu.

But beyond that it's in the 70's every day.

It looks more like a glorified sea breeze

[SnoSki14]

Yeah, I am thinking that we will be able to pull ahead of March 2010 for monthly average temperature.

We'll have to see how long the pattern persists after the 20th or so to know how close to the top we

can get.

Wow 1945 was really warm.

[Isotherm]

Wow 1945 was really warm.

Yeah that equates to a +10 temp departure here, incredible.

[bluewave]

Wow 1945 was really warm.

Yeah that equates to a +10 temp departure here, incredible.

Yeah, that 45 pattern was able to really dominate a good portion of the month.

Central Park's new March mean is 42.5 so that it was even more impressive

in an era of colder means.

[uncle W]

the winter of 1945 started eraly and ended early...March and April 1945 were warm but June started out with the coldest first week on record and coldest tempertaure...June 45 ended with near record heat...It was a roller coaster year...January 45 was very cold...Unlike this years January...

[bluewave]

the winter of 1945 started eraly and ended early...March and April 1945 were warm but June started out with the coldest first week on record and coldest tempertaure...June 45 ended with near record heat...It was a roller coaster year...January 45 was very cold...Unlike this years January...

Detroit registered almost a 15 degree departure that month relative to the colder means of the time.

http://www.crh.noaa.gov/dtx/march.php

[NYCSuburbs]

Although this time frame undoubtedly is very warm for March, it doesn't look to me like a full blown torch for even part of the time... that back door cold front signal has been showing up since yesterday morning on the ECM before the other models started to catch onto it and are still trending towards, and while the ECM originally overdid the extent of the cold, Wednesday doesn't look like too much of a warm day (mid 60s, compared to possible low 70s on Tues), and Thursday is also questionable, as the ECM has NYC near the eastern extent of the stronger warmth, while the DGEX easily brings it through and the GFS keeps it much more to the southwest with only low 60s here. Assuming that the back door cold front does come through, I'd go a little colder than the ECM for Thursday with temperatures perhaps similar to those of Wednesday, but with a potential trend for a weaker and much further north cold front on Thursday, perhaps the stronger warmth in NYC could be on Friday into next weekend and next week should the cold front stay far north enough to have almost no influence.

18z GFS showing the colder temperature potential for Thursday:

[forkyfork]

It looks more like a glorified sea breeze

[nzucker]

Just arrived home from NH....starry night in Westchester, and sitting at 39.6/25. Feels crisp after yesterday.

[Isotherm]

00z GFS continues to suggest Mon-Tues are the warmest days this week, with the backdoor idea looking more and more impressive for Wed-Thurs, possibly hanging on late week as sfc winds remain SLY. Late weekend into next week we should reach the height of our "heat" as the Eastern ridge goes wild due to a deepening Western trough.

Meanwhile, beautiful night. 37 and cold. Starlit skies.

[Thunderdude]

Backdoor cold fronts really suck but they are always happen during the transitioning season begins. Monday and Tuesday we will see 60's and possibly near 70 F in the warm spots. Wednesday will probably see early highs in the 50's then dropping through the 40's and probably Thursday will not get out of the 40's while just south will bake. Backdoor cold fronts especially in later April and May ruins thunderstorm or severe weather chances for us.

[earthlight]

The GFS suddenly jumped towards a huge BDCF signal now...with the 500mb trough coming over the top of the ridge and then dropping southeast over New England

http://www.meteo.psu.edu/~gadomski/AVN_0z/f120.gif

The Euro is not as enthused with that idea...but does have a pretty strong signal for a very sharp gradient near the coast. The beaches might stay in the 50's while areas just inland hit the 70's next week.

[Weathergun]

First, Monday has shot of seeing low 70s away from shore. But Tuesday has potential to be even warmer. The GFS and Euro still have a WSW flow developing during the Tuesday afternoon, with 850mb temps pushing +8C. If we can break out early,of clouds and fog, from warm front passage, early, we have shot at seeing mid 70s, away from the shore. It might also be the warmest day, all week between JFK and ISP, with temps possiblly reaching 65 or above.

Second, I'd be wary, right now of the GFS and DGEX with the backdoor cold front midweek. The 500mb low is further south on the GFS, than the ECMWF, UKMET, and GGEM. The lack of a -NAO ridge, also supports the 500mb low tracking further north. However, the models are generally awful at handling cut- off or upper-level lows. How far south that low is, will determine how much of a backdoor cold front or a seabreeze, will see each day Wed thru Friday.

[bluewave]

First, Monday has shot of seeing low 70s away from shore. But Tuesday has potential to be even warmer. The GFS and Euro still have a WSW flow developing during the Tuesday afternoon, with 850mb temps pushing +8C. If we can break out early,of clouds and fog, from warm front passage, early, we have shot at seeing mid 70s, away from the shore. It might also be the warmest day, all week between JFK and ISP, with temps possiblly reaching 65 or above.

Second, I'd be wary, right now of the GFS and DGEX with the backdoor cold front midweek. The 500mb low is further south on the GFS, than the ECMWF, UKMET, and GGEM. The lack of a -NAO ridge, also supports the 500mb low tracking further north. However, the models are generally awful at handling cut- off or upper-level lows. How far south that low is, will determine how much of a backdoor cold front or a seabreeze, will see each day Wed thru Friday.

Yeah, Tuesday looks like the first mid 70's of the season at the warm spots.

[NYCSuburbs]

First, Monday has shot of seeing low 70s away from shore. But Tuesday has potential to be even warmer. The GFS and Euro still have a WSW flow developing during the Tuesday afternoon, with 850mb temps pushing +8C. If we can break out early,of clouds and fog, from warm front passage, early, we have shot at seeing mid 70s, away from the shore. It might also be the warmest day, all week between JFK and ISP, with temps possiblly reaching 65 or above.

Second, I'd be wary, right now of the GFS and DGEX with the backdoor cold front midweek. The 500mb low is further south on the GFS, than the ECMWF, UKMET, and GGEM. The lack of a -NAO ridge, also supports the 500mb low tracking further north. However, the models are generally awful at handling cut- off or upper-level lows. How far south that low is, will determine how much of a backdoor cold front or a seabreeze, will see each day Wed thru Friday.

I agree with you on Tuesday; there's still some cloud cover around, but with WSW winds and the warm 850mb, mid 70s could easily be reached in my opinion away from the coast. The 12z NAM supports this and is even warmer than its previous run. It should also be interesting to see how the models handle the surface temperatures this time; with the last warm spell, they underestimated the surface temperatures, and both Wednesday in the central/north central US and Thursday over here ended up 5-10 degrees warmer than modeled.

The 0z GFS probably overdid the extent of the back door cold front in my opinion, but the idea of the cold front moving through is more likely, with the rest of the models also showing some cooling on Wednesday and/or Thursday before warming back up again by next weekend. As you mentioned though, the models aren't too great with handling cutoffs, so temperatures on Wednesday and Thursday still have some room to change. Next weekend looks warmer, but there's still a slightly cooler and possibly cloudy signal showing up over the region, so while we'd still probably have warmer temperatures going into the week afterwards, it could perhaps end up similar to this upcoming week with a couple of very warm days and other not as warm days.

12z NAM temperatures for Tuesday:

[bluewave]

I agree with you on Tuesday; there's still some cloud cover around, but with WSW winds and the warm 850mb, mid 70s could easily be reached in my opinion away from the coast. The 12z NAM supports this and is even warmer than its previous run. It should also be interesting to see how the models handle the surface temperatures this time; with the last warm spell, they underestimated the surface temperatures, and both Wednesday in the central/north central US and Thursday over here ended up 5-10 degrees warmer than modeled.

The 0z GFS probably overdid the extent of the back door cold front in my opinion, but the idea of the cold front moving through is more likely, with the rest of the models also showing some cooling on Wednesday and/or Thursday before warming back up again by next weekend. As you mentioned though, the models aren't too great with handling cutoffs, so temperatures on Wednesday and Thursday still have some room to change. Next weekend looks warmer, but there's still a slightly cooler and possibly cloudy signal showing up over the region, so while we'd still probably have warmer temperatures going into the week afterwards, it could perhaps end up similar to this upcoming week with a couple of very warm days and other not as warm days.

12z NAM temperatures for Tuesday:

It will be interesting to see how many 20 degree or higher departure days we can rack up before this month is over.

The seven day running departures are pretty much off the charts for this time of year.

[Snow_Miser]

12z GFS looks like it's about 50 to 100 miles or so N with the 0 C 850s associated with the BDCF 4 days from now.

[Snow_Miser]

Yeah, this run of the 12z GFS when compared to the 00z run is much warmer at the 850 mb level. Almost a guarentee that the surface is probably warmer than it was with the 00z run.

[NYCSuburbs]

12z GFS looks like it's about 50 to 100 miles or so N with the 0 C 850s associated with the BDCF 4 days from now.

It actually looks a little colder going into Wednesday night/Thursday, but the cutoff is further north and the originally modeled cold front for late next week is even weaker and more north so far, continuing the trend towards very little, if any influence from the late week cold front and an even bigger period of warmth going into next weekend/week.

[earthlight]

It has been a long time since i've seen such +anomalies modeled literally for 384 hrs

http://www.meteo.psu.edu/~gadomski/ENSHGTAVGNH_6z/ensloopmref.html