17 replies to this topic

[Ray Tampa]

From Accuweather's Henry Margusity

NAO, PNA and La Nina Are Just Ruining Our WinterDec 12, 2011; 9:36 AM ET
Discussion
Videos will resume on Wednesday when I am back in the office. In the meantime, the weather pattern, while stormy, is not the one snow lovers in the eastern part of the country want to see prior to Christmas.

Here is why....

La Nina - Remains weak, so pattern remains typical of a La Nina with the cold weather in the West and northern Plains and the warmth across the East. The storm track has been from the southwest to the western Great Lakes.

NAO - North Atlantic Oscillation remains positive, so no blocking and therefore no East Coast storms for major snowstorms. When the NAO goes negative, watch out.

PNA - Pacific/North America Pattern remains neutral and now looks like it will go negative. What does that mean....trough and cold in the West and warmth/ridge in the East -- this is not good for snowstorms in the East, but Western ski resorts will be rejoicing!

I really don't see much in the way of changes to the current pattern. While we will see storms, especially this week, the snow problems will be limited to areas where the cold can hold its ground long enough to allow for some snow. I do think the western Great Lakes and northern Plains have the best chance of snow prior to Christmas.

I know a lot of you been looking at the storm around Christmas. Again, until we can get any of these indices to change, I would not get all that excited for major snowstorms in the eastern part of the country. It surely is a big change from the past two years.

[PalmatierMeg]

RE: East Coast winter, lack thereof

That's the kind of news that warms my heart and makes my palms happy. After the past 2 winters I was dreading this one. Ray, thanks for your reporting of weather trends. Keep us up to date often.

[gsytch]

Yes, all weathermen have been talking about that, even going into the first week of Jan witht his pattern. It is kinda odd, after the past two winters, to sit here with doors and windows open and a balmy breeze blowing in. I checked last year and we were beginning the dive down with a Tampa freeze already in the books. I would just hate to see the pattern reverse in Feb after plants begin growing anew. Just a hope!

[Eric in Orlando]

I hope it is like this all winter, we don't need a 3rd cold one in a row here in FL.

Looked up our weather records from last year and on 12/13/2010 it was a high of 47F and a low of 35F here, uggggh. A year ago tommorow was worse, an early freeze last year. 12/14/2010 had a high of 48F and a low of 29F.

Warm all this week, hope it doesn't change.

[Ray Tampa]

Eric,

If it stayed this way all winter, we'd set a record for the warmest on record. I expect some colder weather in January with a freeze almost guaranteed at some point. One cool/cold shot like we get most years is tolerable and does minimal if any damage. It's the persistent cold of January and December 2010 that are brutal. If protective measures are taken, I still say those persistent cold patterns are worse than the quick frigid shot like 1989.

Ray

[BS Man about Palms]

gee, if it makes you feel any better, We are getting all your winter...

I have never seen SO MANY "in the 30's" overnight temps here since I started collecting palms! It looks we will hit close to 3 weeks with only 4 or 5 days NOT in the 30's overnight here! ACK!


I suspect this is gonna be a tough winter here.

[palmsOrl]

Quick update - still unseasonably warm here in Central Florida. Looks like more of the same for at least the next week with highs forecast to be as warm as 82F. This is starting to remind me of a January 5-6 years ago, where we had highs 82-83F and lows in the low 60s with almost daily rain showers (okay, we are barely getting any rain now) for weeks on end, local meteorologist Tom Terry had termed this "summer-lite". I am thrilled to see full canopies continuing to fill-in on my large royals and am considering taking the Cyrtostachys out of the greenhouse. As for myself, I wouldn't mind some more days in the 50s and 60s as this feels so refreshing.

-Michael

[PalmatierMeg]

For the next 10 days highs to be upper 70s to low 80s, lows from mid-60s to mid-50s. I'm so thankful because my niece won't have to roll the Cyrtostachys into/out of the house over Christmas. That's an answer to my Christmas wish.

[Dave-Vero]

The National Weather Service indicates cool weather sometime beyond a week from now....but so far, no predictions of calamity.

[Ray Tampa]

As long as the Arctic Oscillation stays positive, no trough will stay in the east for very long. As of yesterday, the AO is to stay positive through at least the first week of January.

[Mandrew968]

Ray, you have me looking up Arctic Oscillation; I am always greatful to anyone who gives me more knowledge to better trek this Earth--Thanks

WIKI-Dr. James Hansen explains the mechanism by which the AO affects weather at points so distant from the Arctic: "The degree to which Arctic air penetrates into middle latitudes is related to the AO index, which is defined by surface atmospheric pressure patterns. When the AO index is positive, surface pressure is low in the polar region. This helps the middle latitude jet stream to blow strongly and consistently from west to east, thus keeping cold Arctic air locked in the polar region. When the AO index is negative, there tends to be high pressure in the polar region, weaker zonal winds, and greater movement of frigid polar air into middle latitudes."

[Dave-Vero]

Florida is continuing to look warm through New Year and a bit beyond. This graph from the National Weather Service shows just how balmy November and December have been.
As you can see, January has historically had some horrific cold.

[Ray Tampa]

As of this morning, the NAO and AO both are trending towards negative . This changes daily but keep an eye on the trends.

[gsytch]

What is the best, easiest site for the AO. I've been keeping up on it, but many of the sites are rather complex and wordy. I just want the "short and sweet" story....Thanks!

[Ray Tampa]

Forget everything I've posted before this. There's a big, big trough headed east next week and a central Florida freeze is almost a certainty. I've seen this too many times to believe any of the numbers in the forecast now. The lows will tumble as each subsequent forecast is released. Happy &#$@?! New Year.

[palmsOrl]

Yeah, Accuweather was calling for a low of 33F on January 3 last night. Even during the mildest winters, we get a night or two in the low 30s (Airports may not register below 33-34F). Are there still indications that the NAO is trending toward negative?

-Michael

[gsytch]

Don't look now, but there are freeze warnings all the way to the Everglades! The only saving grace might be the relatively warmer GOM and its influence. Warmth followed by a windy freeze.....not good! Figures we couldn't get away with it.

[Moose]

Some unhappy plants were found in the Moose Land at sunrise.