May 2014

[famartin]

Ensembles in good agreement on a cool start to May with no meaningful warm ups in the distant future. Rain also looks to be above average as we head into May.

I just pulled up the stats on Weather underground (07444)

 

May 1 +10

May 2 -4

May 3 +1

May 4 -5

May 5 +3

 

Overall temperature departure = +5 which is being skewed by the one +10 departure day on May 5th.

 

Now if we look at April 29th and April 30th.

 

April 29 -14

April 30 -14

 

So the last two days of April were -28.

 

So since I made my post on 4/28 I've been a grand total of -23F below normal.

 

I just quoted you again.  You said "May".  Not anything about counting April in that equation.

[famartin]

The last seven days, where did I say anything referencing specifically the month of April?

Are you daft?  I quoted you.

[IsentropicLift]

So the fact of the matter is Caldwell was ~21.2% below normal the last two days of April and ~1.5% above normal the first five days of May.

[famartin]

So the fact of the matter is Caldwell was ~21.2% below normal the last two days of April and ~1.5% above normal the first five days of May.

You didn't say anything about April.  Which make sense since this thread is entitled "May 2014". 

[IsentropicLift]

I just quoted you again.  You said "May".  Not anything about counting April in that equation.

Even if you go by only the first five days of May it's a +5 departure but it's clearly being skewed by the +10 departure on May 1st.

 

And my original post which Forky called out was made on April 28th so if you're going to tell me I'm wrong you need to include all of the days which occurred since the post.

[IsentropicLift]

You didn't say anything about April.  Which make sense since this thread is entitled "May 2014". 

I think you're misunderstanding me. Forky called me out about a post made April 28th.

[famartin]

Even if you go by only the first five days of May it's a +5 departure but it's clearly being skewed by the +10 departure on May 1st.

 

Any my original post which Forky called out was made on April 28th so if you're going to tell me I'm wrong you need to include all of the days which occurred since the post.

No I don't.  You said "start of May".  What part of the English language are you having trouble comprehending here?  I'm just curious.

[Isotherm]

Often times the tale of the month is told in the beginning 7-10 days. If one looks back at NYC's departure in days 1-10 of the month, one would find that most of the time, the month's temperature departure coincides with the departure of the first 10 days (above or below normal).

 

I anticipate the overall temp departure map for May to look fairly similar to the current anomalies for May thus far. Slightly warmer than normal for the I-95 corridor, colder than normal in the Lakes / Mid-west, and warmer than normal in the western US.

 

NYC is +3.3 for May temperatures so far, and the next 7-8 days should be warmer than normal, with the potential for 75F+ days on Saturday, Sunday, and early/mid next week.

 

 

 

 

 

 

 

In terms of the bigger picture, the persistent negative EPO isn't changing, but a negative EPO at this time of year does not necessarily mean cold weather on a persistent time frame for the east coast.

 

The modalities of both the AO and NAO look to remain positive for the forseeable future, which should create quite a bit of resistance to incoming troughs near the east coast. Last summer (2013) featured a -EPO, but the strongly positive NAO allowed the west atlantic ridge to remain powerful for the I-95 corridor's temperatures, resulting in a slightly warmer than normal summer. I'll have my summer outlook around the end of May as well, but we could see a regime similar to 2013 w/ the -EPO / +NAO couplet. However, I'm waiting to see how the rest of May progresses.

 

 

For this month, the analog of 2009 had a robust -EPO in concert w/ the positive NAO. The result was slightly warmer than average temps overall in the Northeast corridor. 2009 was also the last oncoming El Nino season.

 

 

 

The 500mb composite of milder than normal May's since 2000 show the negative anomalies / +NAO & AO, with a slightly negative EPO.

 

 

 

 

I don't believe we'll find ourselves in the group of blowtorch May's, as the blocking in the EPO regions is just too powerful. However, I do believe the flavor of the next 3 weeks is near normal to slightly above normal overall, enough to give NYC a +1 or so temp departure for May. There will be cool shots interspersed, especially the May 15th-18th period, but I see some potential for occasional heat as well.

[IsentropicLift]

And yes I see where I said "a cool start to May" and barring one fluke day that has been the case. Yes one day the sun came out and things briefly warmed up. I remember my car hitting 81 degrees on the way home from work.

 

If you take out the +10 on May first Caldwell has been -5 thus far in May 2014.

[famartin]

And yes I see where I said "a cool start to May" and barring one fluke day that has been the case. Yes one day the sun came out and things briefly warmed up. I remember my car hitting 81 degrees on the way home from work.

One fluke?  Your own stats list 3... count them, 3... days above normal.  I wouldn't say that's one fluke.  Yes, one of those 3 days was WELL above normal, but when you get right down to it, more days have been + than have been -.

[IsentropicLift]

Precip has been 0.20" versus average of 0.63" or ~31.7% of average. Come talk to me at the end of May and we'll see what kind of departures we end up with.

[Isotherm]

When we total the months of April and May 2014, I think most locations will be very close to normal or maybe slightly above (about a -0.5 to -1.5 April followed by a +0.5 to +1.5 May). Meteorological spring will come in solidly colder than normal due to March though.

[IsentropicLift]

One fluke?  Your own stats list 3... count them, 3... days above normal.  I wouldn't say that's one fluke.  Yes, one of those 3 days was WELL above normal, but when you get right down to it, more days have been + than have been -.

If you take out the two extremes of +10 and -5 the temperature departure from average is exactly 0.

[IsentropicLift]

Furthermore the forecasted dive next week of the NAO supports below average temperatures and above average rainfall.

 

[Stormlover74]

If you take out the two extremes of +10 and -5 the temperature departure from average is exactly 0.

so it's been a very average start with some above normal temps on the way meaning through mid month we'll likely be running about normal. also we average 1 to 1.25 inches of rain per week this time of year. Many places won't even see that much this week (the euro has .5-.75" thru Saturday)

[IsentropicLift]

so it's been a very average start with some above normal temps on the way meaning through mid month will likely be running about normal

We're dealing with a very small sampling thus far of only five days but yes overall we've been about average. If the cut off low next week materializes we'll see below average temperatures.

 

This time of year it's very easy to get a few days well above normal with full sunshine and southwest flow so often the mean temperature departure isn't a good representation of the overall monthly pattern.

[famartin]

Furthermore the forecasted dive next week of the NAO supports below average temperatures and above average rainfall.

 

NAO influence decreases steadily towards nil as you head from winter to summer, at least when it comes to temperature departures.

 

http://www.cpc.ncep.noaa.gov/data/teledoc/nao_tmap.shtml

[famartin]

so it's been a very average start with some above normal temps on the way meaning through mid month we'll likely be running about normal. also we average 1 to 1.25 inches of rain per week this time of year. Many places won't even see that much this week (the euro has .5-.75" thru Saturday)

We're dealing with a very small sampling thus far of only five days but yes overall we've been about average. If the cut off low next week materializes we'll see below average temperatures.

 

This time of year it's very easy to get a few days well above normal with full sunshine and southwest flow so often the mean temperature departure isn't a good representation of the overall monthly pattern.

 

You can't pick and choose which days to include in your average.  Climo doesn't work like that.

[IsentropicLift]

NAO influence decreases steadily towards nil as you head from winter to summer, at least when it comes to temperature departures.

 

http://www.cpc.ncep.noaa.gov/data/teledoc/nao_tmap.shtml

A negative NAO favors troughing in the east and troughing favors clouds and rain and clouds and rain generally keep temperatures at bay.

[IsentropicLift]

You can't pick and choose which days to include in your average.  Climo doesn't work like that.

So lets include the last seven days shall we?

 

-23.

[famartin]

A negative NAO favors troughing in the east and troughing favors clouds and rain and clouds and rain generally keep temperatures at bay.

In winter, yes.  As you head into the warm season, the wavelengths change, so the teleconnections do also.  Thus, negative NAO in winter doesn't mean the same as negative NAO in summer.

[famartin]

So lets include the last seven days shall we?

 

-23.

You were the one who said "May".  Your *original* rules.

[IsentropicLift]

You were the one who said "May".  Your *original* rules.

Congrats, you win on a dumb technicality because I wasn't careful enough with my words.

[IsentropicLift]

In winter, yes.  As you head into the warm season, the wavelengths change, so the teleconnections do also.  Thus, negative NAO in winter doesn't mean the same as negative NAO in summer.

Well aware, and it's May 6th, not July 6th. 45 days since the Spring equinox and 46 days from the Summer solstice so technically speaking today we're just as close to winter as we are Summer.

[famartin]

Well aware, and it's May 6th, not July 6th. 45 days since the Spring equinox and 46 days from the Summer solstice so technically speaking today we're just as close to winter as we are Summer.

Except that the middle of winter (as noted in the chart I linked) is considered January, and summer July.  The influence as noted in the link is already fading in April, so would be even less in May.  We're certainly much closer to July 1st (55 days) than we are to January 31st (94 days).

[IsentropicLift]

FWIW the 12z ECMWF looks very similar to the 12z GGEM days 7-10. Both develop what looks to be a weak tropical low east of Florida and pull it north up the coast.

[IsentropicLift]

 

[IsentropicLift]

Looks, ummm dry

 

 

[IsentropicLift]

Nice soaking rain tomorrow for most of the area

 

[Shades]

Nice soaking rain tomorrow for most of the area

 

If you're going to rain monger, at least get your dates right ... the rain doesn't arrive until late tomorrow night/more likely after midnight/early Thursday. Everyone will be dry tomorrow, certainly during the day, and no one should carry an umbrella unless they are using it for shade... clouds won't even really increase substantially until the afternoon. Overall, it will be another pleasant Spring day.