Medium/Long Range thread

[HM]

The implications of this would be a "lid" on the climo "peak" of severe weather early May over the S-C Plains but possibly rapidly picking up post-peak (mid-late May). After the -AO wave peaks and relaxes/develops stronger swings and possibly an organized MJO wave through the IO-Indonesian Sector, things could peak a little later than normal (second half of May-early June).

Perhaps as we get a little closer, I'll start throwing out dates, for fun, for potential significant severe weather outbreaks. A post -AO peak in a warmer time of year and tropical forcing shifting from Atlantic to IO-Indo on the cusp of a burgeoning S-C Plains summertime anticyclone suggests this round could be a lot worse than the current period. But it is too early to say.

[tombo82685]

Do -nao's during summer translate to the same as winter with cooler/wet weather? Also, do they lead to a better chance of severe weather? What is a textbook severe weather outbreak/scenario for us?

[CooL]

Do -nao's during summer translate to the same as winter with cooler/wet weather? Also, do they lead to a better chance of severe weather? What is a textbook severe weather outbreak/scenario for us?

 

I've read that as we get towards late May ino August, a -NAO has a much more limited influence on our temps when compared to winter. Im not sure about the -AO though

[am19psu]

Here are -NAO composites by month from Ellinwood:

 

http://madusweather.com/teleconnection/nao_neg.php

 

And the -AO for good measure:

 

http://madusweather.com/teleconnection/ao_neg.php

[NaoPos]

Do -nao's during summer translate to the same as winter with cooler/wet weather? Also, do they lead to a better chance of severe weather? What is a textbook severe weather outbreak/scenario for us?

I've seen instances where we can torch with a -NAO due to the se ridge hooking up with it. I'm sure it has less influence due to wavelengths and such.

[Isotherm]

ENSO state/progression as well as PDO and AMO tend to have greater influences in the summer. Summer blocking /-NAO/-AO patterns have frequently yielded torch regimes in the CONUS.

[andyhb]

The implications of this would be a "lid" on the climo "peak" of severe weather early May over the S-C Plains but possibly rapidly picking up post-peak (mid-late May). After the -AO wave peaks and relaxes/develops stronger swings and possibly an organized MJO wave through the IO-Indonesian Sector, things could peak a little later than normal (second half of May-early June).

Perhaps as we get a little closer, I'll start throwing out dates, for fun, for potential significant severe weather outbreaks. A post -AO peak in a warmer time of year and tropical forcing shifting from Atlantic to IO-Indo on the cusp of a burgeoning S-C Plains summertime anticyclone suggests this round could be a lot worse than the current period. But it is too early to say.

 

Good stuff here HM, while most would admit that another -AO spike is certainly not what a lot of the chasers are looking for, if it means that the following pattern could be active and more productive than we have seen recently, I'm sure that would be a good enough compromise.

[HM]

 

Good stuff here HM, while most would admit that another -AO spike is certainly not what a lot of the chasers are looking for, if it means that the following pattern could be active and more productive than we have seen recently, I'm sure that would be a good enough compromise.

 

Hey don't worry about it. Getting things to be a little out of phase during the peak season isn't the worst thing. You still are going to get threats down there. It is analogous to hurricane season when we get a convergence h2 wave moving the Atlantic in early September...you still are going to get a tropical storm.

There is something early 80s and early 90s like with the late winter / early spring pattern. A lot of those years really ramped up in May when the perfect balance of summer's approaching warmth and winter's leftover jet stream delivered the goods. Clearly, March and April this year had too much of winter's influence.

[andyhb]

 

 

Hey don't worry about it. Getting things to be a little out of phase during the peak season isn't the worst thing. You still are going to get threats down there. It is analogous to hurricane season when we get a convergence h2 wave moving the Atlantic in early September...you still are going to get a tropical storm.

There is something early 80s and early 90s like with the late winter / early spring pattern. A lot of those years really ramped up in May when the perfect balance of summer's approaching warmth and winter's leftover jet stream delivered the goods. Clearly, March and April this year had too much of winter's influence.

 

Yes, I believe Tony had this prediction in that thread on C/W, that the March/April threats would be suppressed and overall less active than the past two years, which has certainly been the case so far. Several of the early 80s/90s years had some potent events in June as well. (6/7-8/84, 6/2/90, 6/16-17/92, etc.)

[ptb127]

I wish there were more heat/warmth enthusiasts on here! But again, there hasn't been much to talk about.

 

I am seeing signs on the models of a Chinook wind setup for the N Mid Atl... that have a chance of setting up?

[Rainshadow]

Here are -NAO composites by month from Ellinwood:

 

http://madusweather.com/teleconnection/nao_neg.php

 

And the -AO for good measure:

 

http://madusweather.com/teleconnection/ao_neg.php

 

That makes sense for October and that 60/40 "flip" of the October NAO and ensuing winter temps.

[NaoPos]

........

[tombo82685]

........

Pretty good nao block in that with pna ridge out west

[Rainshadow]

Pretty good nao block in that with pna ridge out west

 

I'm in no rush to plant vegetables this spring.  BTW April is not as good as October is, but there is still about a 60/40 the way April goes, the summer goes.

[famartin]

I'm in no rush to plant vegetables this spring.  BTW April is not as good as October is, but there is still about a 60/40 the way April goes, the summer goes.

So about +3 across the area is a good sign for a hot summer then?

[Mitchell Gaines]

+1 to +3 would make sense for the summer which is the likely range of temp departures for April. Those two record days earlier this month will have less effect on the mean as the month moves on.

[ptb127]

+1 to +3 would be a pretty hot summer actually. Isn't it harder to get those positive departures as the normals continue to rise until they get their peak in Mid July??

[famartin]

+1 to +3 would be a pretty hot summer actually. Isn't it harder to get those positive departures as the normals continue to rise until they get their peak in Mid July??

Generally, but its also harder to get larger departures over longer periods given natural fluctuations.

 

I think the "normal" PHL summer average temperature is about 76.  Here are all the summers which averaged 77 or more:

  1    79.6    2010  2    78.6    1995  3    78.3    1994  4    78.2    1993  5    78.0    2012,  2011  7    77.9    1991  8    77.8    2005  9    77.7    2002 10    77.2    1999,  1900 12    77.1    1988,  1973

[Rainshadow]

So about +3 across the area is a good sign for a hot summer then?

It would seem difficult to buck the recent trend. I know its not on par with these other years, but there have been hot summers near solar maxima too (1980, 1991 & 2002).  At least its been raining in the Midwest, so maybe the heat ridge will establish itself farther to the west this summer and we stay more in a northwest flow regime.

[famartin]

It would seem difficult to buck the recent trend. I know its not on par with these other years, but there have been hot summers near solar maxima too (1980, 1991 & 2002).  At least its been raining in the Midwest, so maybe the heat ridge will establish itself farther to the west this summer and we stay more in a northwest flow regime.

So I'll enjoy a broiling, smokey inferno?

[NaoPos]

Doesn't look like any sustained warm up relative to average in the medium range. MJO seems fairly benign for the next couple of weeks.

NOt too bad temp wise, i'm just not a big fan of the breezy days. Makes my golf game that much worse. lol.

Intreresting to note, this average to below normal temps have come with a healthy +NAO signal:

We just seem to be under the influence of the Canadian maritime HP Northeast of us.

Even as we get to 240+hours, you can see the cooler air alongside the east coast.

[am19psu]

Get ready for the neverending CAD/marine layer

[Mike.Ventrice]

Get ready for the neverending CAD/marine layer

[tombo82685]

Get ready for the neverending CAD/marine layer

we were due for it. We haven't had one of those horrid stretches in a couple of years.

[dryslotted]

we were due for it. We haven't had one of those horrid stretches in a couple of years.

 

Summer 2009 redux?

[am19psu]

Summer 2009 redux?

When I said neverending, remember my crystal ball only goes out about a month

[forkyfork]

Get ready for the neverending CAD/marine layer

grumpy cat?

[Quakertown needs snow]

When I said neverending, remember my crystal ball only goes out about a month

others go out over 1 month... come on adam you can do it

[Mike.Ventrice]

 

 

AO forecast to run through phases 7->1 this upcoming.. Temp comps show good warmth over northern Plains and colder than average weather over Mid Atlantic/Southeast in this phase space... not a bad match

 

[am19psu]

Interesting that none of the composites show warmth east of the Appalachians. I wonder if something else (ENSO? MJO? SSTAs?) modulates Mid-Atlantic weather in during this period.