Florida Weather

[asd123]

:uarrow:Yeah, I read what Cosgrove mentioned. I would say that it is definitely plausible to see arctic air invade down across the Eastern CONUS during the period from December 15-22. However , for Florida as a whole to really get impacted by arctic cold, again the NAO has to go negative asd123. As I mentioned earlier, we haven't really seen the NAO tank significantly to bring arctic air deep into the Florida peninsula since January 2010.

I kind of look at Central and South Florida's extreme cold escapes as a blessing. I compare it to the peninsula missing getting impacted by major hurricanes going now towards 10 years.. However, at some point, our luck will run out eventually and either situation is going to happen.

A long ways to go though, and tomorrow marks the beginning of the meteorological start of the winter 2014-15 season.

Actually December 2010 was the last time the NAO really tanked negative. I remember on the morning of December 14th, 2010 it got down to 30.3°F at my house here in Palm Beach Gardens, FL! I have proof as well.

http://i61.tinypic.com/oua22q.jpg

You're right, TheStormExpert and the NAO tanked in late Novemeber early December, lower NAO values than 2009-2010 winter. ftp://ftp.cpc.ncep.noaa.gov/cwlinks/nor ... rent.ascii

Personally, I think not only the NAO can bring severe cold to cfla. It's more than one factor.
In January 1985 Orlando saw its all time record low of 19F and the NAO was higher at that time than December 2010. 12/2010 was not warm for cfla but not a severe arctic air mass. Like northjaxpro said, the NAO does play a significant role in bringing Florida arctic air. But the severity of an arctic air mass is probably determined by other factors.

[northjaxpro]

Thanks for the correction StormExpert. My memory deceived me with the month, although I did recall 2010 as the year.

[TheStormExpert]

Thanks for the correction StormExpert. My memory deceived me with the month, although I did recall 2010 as the year.

Yeah 2010 winter months were all bitter/brutally cold for us here in Florida as a whole. In fact that temperature I mentioned above was colder by two degrees than the coldest temperature recorded during the early months of 2010(Jan-Mar).


I hope this winter is not anywhere near the extreme like those months, though I do like the cool/cold weather here in S. FL after dealing with nonstop heat year round.

[northjaxpro]

I saw asd123's reference to the historic January 1985 arctic outbreak. That was really a very extreme event to say the least with such a massive displacement of the polar vortex.

I remembered this event so well and its effects caused major problems here in Jax. Many all time records were established all across the Eastern U.S. and Canada. The all-time record low temp of 7 degrees was recorded here during that event. The polar vortex had actually dropped southeast into Maine, something that is extremely rare. The cold was locked into place for an extended time all across the entire Eastern U.S., about 10 days. Everything from the pipes at my home at the time, to car radiators froze completely lol.. It was just unbelievable the magnitude of that cold that year.

I love going back to analyze that event. It was incredible to see such a powerful cold wave. It has been nearly 30 years since that event, which really highlights these type of events are just about once and a lifetime extremes for sure.

[asd123]

Crazy GEM:
Doesn't the GEM care that the AO is going to be neutral to positive and the NAO positive and that it doesn't have other models' support?

Image courtesy of Tropical Tidbits

[BigB0882]

Haven't their been hints that the NAO may go negative by mid December? I hope it does, isn't that an absolute key part to getting cold to funnel down south?

[gatorcane]

Crazy GEM:
Doesn't the GEM care that the AO is going to be neutral to positive and the NAO positive and that it doesn't have other models' support?

Image courtesy of Tropical Tidbits
http://i61.tinypic.com/2h2ibo0.jpg

Some very cold anomalies for the SE US and Florida on the long-range GEM. Going to need ECMWF or GFS support before I am a believer

[NDG]

The teleconnections we had for Nov 18-20 was a -AO and +PNA, but the NAO was neutral. North and Central Florida overall generally experiences a considerable cooldown when these indicators are present. Freezes, and even hard freezes, often occur mainly well north of the I-4 corridor across North Florida with this set-up, which happened the week before last. However, without a strongly negative NAO, we don't have the upper level flow straight out of the north and northwest from the polar regions to dive the coldest of the arctic air mass deep down the spine of the Florida peninsula. It would be quite unusual to see Central and South Florida get freezes without a - NAO.

asd123, keep an eye for the middle of the December. I think by then we may have a pattern shift with regards to the teleconnections for a potential return to a -AO and +PNA spike. But, all rides on the NAO. We have been really very fortunate here in Florida that the NAO hasn't tanked significantly to bring severe cold since January 2010. If the NAO doesn't dip significantly negative this winter, it generally bodes well for my neighbors down from the I-4 corridor and all areas southward as with regards to escaping freezes.

I am definitely keeping an eye out for the second half of December. Did you see the quote from Larry Cosgrove? http://forums.accuweather.com/index.php ... start=1060 Go to second post, note the quote from Larry Cosgrove.

Those are some powerful words he used: "...will send the brutal reality of winter cold as far south as Mexico and Cuba."

Given what he has said, do you think this will happen:

(Image info: Link to license: http://creativecommons.org/licenses/by/4.0/ Image courtesy of Craig ONeal on flickr.com):

http://i58.tinypic.com/287bkj.jpg

IMO, the best way to look at the long range forecast is to look at the trends and or persistent pattern during the past couple of months.
In this case the NAO has been mostly in the neutral to positive phase for the most part and with the ensembles showing the NAO to stay positive through the middle of the month it will be hard to believe that the NAO will turn sharply negative before the end of the month.
So in another words, hard to believe that Arctic air will move as far south as Cuba before Christmas as Larry Cosgrove mentions.

[NDG]

Thanks for the correction StormExpert. My memory deceived me with the month, although I did recall 2010 as the year.

Yeah 2010 winter months were all bitter/brutally cold for us here in Florida as a whole. In fact that temperature I mentioned above was colder by two degrees than the coldest temperature recorded during the early months of 2010(Jan-Mar).


I hope this winter is not anywhere near the extreme like those months, though I do like the cool/cold weather here in S. FL after dealing with nonstop heat year round.

2010 Florida got hit twice in the same year with devastating freezes for central FL and parts of south FL.
January 2010 and December of 2010, with December being the coldest month many parts of FL experienced ever since records started.

[NDG]

:uarrow:Yeah, I read what Cosgrove mentioned. I would say that it is definitely plausible to see arctic air invade down across the Eastern CONUS during the period from December 15-22. However , for Florida as a whole to really get impacted by arctic cold, again the NAO has to go negative asd123. As I mentioned earlier, we haven't really seen the NAO tank significantly to bring arctic air deep into the Florida peninsula since January 2010.

I kind of look at Central and South Florida's extreme cold escapes as a blessing. I compare it to the peninsula missing getting impacted by major hurricanes going now towards 10 years.. However, at some point, our luck will run out eventually and either situation is going to happen.

A long ways to go though, and tomorrow marks the beginning of the meteorological start of the winter 2014-15 season.

Actually December 2010 was the last time the NAO really tanked negative. I remember on the morning of December 14th, 2010 it got down to 30.3°F at my house here in Palm Beach Gardens, FL! I have proof as well.

http://i61.tinypic.com/oua22q.jpg

You're right, TheStormExpert and the NAO tanked in late Novemeber early December, lower NAO values than 2009-2010 winter. ftp://ftp.cpc.ncep.noaa.gov/cwlinks/nor ... rent.ascii

Personally, I think not only the NAO can bring severe cold to cfla. It's more than one factor.
In January 1985 Orlando saw its all time record low of 19F and the NAO was higher at that time than December 2010. 12/2010 was not warm for cfla but not a severe arctic air mass. Like northjaxpro said, the NAO does play a significant role in bringing Florida arctic air. But the severity of an arctic air mass is probably determined by other factors.

The NAO might have been higher in January '85 than Nov/Dec '10 but it was still way negative with a -1.61 average for the month. The big difference to 2010 is that in January 1985 was the airmass that came down to the continental US was way colder than in Dec 2010.

[northjaxpro]

Well, this Indian Summer weather looks to continue deep into this month. It has been unbelievable, but with the positive NAO in full effect, there are no indications of seeing any shift in pattern to bring colder air back to the Florida peninsula for at least the next two weeks.

[TheStormExpert]

Well, this Indian Summer weather looks to continue deep into this month. It has been unbelievable, but with the positive NAO in full effect, there are no indications of seeing any shift in pattern to bring colder air back to the Florida peninsula for at least the next two weeks.

What are you talking about? Down here in SE Florida we are expected to have lows down into the 50's for a few nights with highs come midweek struggling to get into the low 70's! For South Florida standards that is definitely not what I would call close to an Indian Summer (Which btw is usually highs in the mid 80's here).

And yes I understand the positive NAO might be allowing for more above average temps. the further up the state you go.

[northjaxpro]

Well, this Indian Summer weather looks to continue deep into this month. It has been unbelievable, but with the positive NAO in full effect, there are no indications of seeing any shift in pattern to bring colder air back to the Florida peninsula for at least the next two weeks.

What are you talking about? Down here in SE Florida we are expected to have lows down into the 50's for a few nights with highs come midweek struggling to get into the low 70's! For South Florida standards that is definitely not what I would call close to an Indian Summer (Which btw is usually highs in the mid 80's here).

And yes I understand the positive NAO might be allowing for more above average temps. the further up the state you go.

Well, pardon me for not being a bit more specific! I am talking about significantly below average cold StormExpert as a whole. A significant polar airmass to bring colder weather is what I am referencing. I am here in North Florida, and I certainly understand the averages here compared to South Florida. That needs no explanation to me. But, in terms of significantly colder weather, none is coming anytime soon to the peninsula as a whole. I just want to specify this clarification to you. I will say we have had Indian Summer type weather here in Northeast Florida this past week, with lows only getting to near 60 and highs near 80 nearly every day this past week and dry weather to come along with it. That is about 15 degrees above the averages here. Jacksonville average lows this time of the year is generally in the mid 40s and highs in the mid 60s for early December.

We will only briefly cool down the first part of this week as a cool front moves through to bring our temps back to near averages. But, look for temps to get back above average by the end of this upcoming week.

[SFLcane]

ECM still trending colder has temps well into the 40's and even some 30's into florida. South Florida could see mid-upper 40's thurs. possibly a prolonged cold snap.

[northjaxpro]

To my surprise, the model runs have trended colder for this week. Initially, they were only showing a cooldown to bring us to near our normal averages for this time of the year. NAO still positive, so I am not anticipating extreme cold. It would be really unusual to see that happen. Will check future runs to see if colder trend continues. We had a week's worth of well above average temps here. However, with the passage of the cold front last night, much different story today. Currently, 56.3 degrees here at my ponderosa with light rain and fog with north/northeast winds around 15 mph. It is a pretty raw day for sure. What a difference a day makes. Measured a max temp of 80 degrees yesterday.

[Sanibel]

Another cool dip this week.

[asd123]

:uarrow: To my surprise, the model runs have trended colder for this week. Initially, they were only showing a cooldown to bring us to near our normal averages for this time of the year. NAO still positive, so I am not anticipating extreme cold. It would be really unusual to see that happen. Will check future runs to see if colder trend continues. We had a week's worth of well above average temps here. However, with the passage of the cold front last night, much different story today. Currently, 56.3 degrees here at my ponderosa with light rain and fog with north/northeast winds around 15 mph. It is a pretty raw day for sure. What a difference a day makes. Measured a max temp of 80 degrees yesterday.

My conversation with NTXW (teleconnections expert) on Texas Winter Weather Thread

NTXW, what is your take on the teleconnections forecast? We are heading deep into December with a +AO, +NAO, +PNA (only favorable one for cold air, need others), and a neutral EPO, source: http://www.daculaweather.com/4_teleconn ... graphs.php, other NOAA) When will the teleconnections change and deliver Arctic air to the Southeast and Texas (wanted your expertise and this is the Texas thread, so had to mention Texas )

AO likely goes negative after the 15-20th period. Strengthening Asian jet will pull back the Aleutian low out of the GOA, but I'm a little uncertain on the EPO if it will go slightly negative or strong, it's a cold loading signal but at this time nothing screams strong deviation from normal. CFSv2 shows a more severe -EPO signal first week of January.

The NAO I'm more muddled on, I've never liked this index because its complicated and there are different outcomes for the same signal but if the southeast wants some arctic intrusion they'll likely need at least a west based (Greenland block) -NAO. In the past severe outbreaks in SEC land (1985 for example) had extreme blocking move from the NAO domain through the AO. Guidance doesn't show much deviation either or for the NAO mostly weakly positive. PNA remains positive most of this winter, El Nino loves it.

Outlook on Deep South Winter Weather Thread:

The models are trending toward a chilly next 10 days: ECMWF has upper 30s for several nights for cfla. and upper 50s low 60s highs. The GEM and its ensembles have also lined up with the Euro on a chilly 10 days for cfla. The GFS too is starting to line up. Beyond the 10 days, it warms up a little bit according to the models, but after that, there might be an overall trend towards colder weather! This is all strange, as the teleconnections seem to be very unfavorable for this prolonged chilliness.

I will highlight the ECMWF which seems colder than all the models, can't really post every single image or loop. I shall invite you to see the loops on Tropical Tidbits of the GFS, GEM, GEM ENS, and ECMWF

All images below courtesy of Tropical Tidbits:

ECMWF 850 mb temp maps:



OOH a little pocket of -850 mb temps in the entire southeast!!!:

PNA and AO is good enough, says NTXW (Deep South Winter Weather Discussion):

For asd123 who mentioned something over in the Texas thread I decided to take a look at some significant 20th century freezes for Florida. It seems cold signal and loading for the southeast as well had a lot in common. The strongest signal I saw that was persistent is the PNA. It was mostly positive for all of these events. -NAO when present seemed to magnify the effects. It also seems the negative anomalies were centered over the Eastern seaboard. PNA this season has been very positive so far, I would put a Florida "impactful" freeze risk above average this season.

http://i57.tinypic.com/inda55.gif

http://i58.tinypic.com/1zfkbp3.gif

http://i57.tinypic.com/2hpjgxe.gif

http://i59.tinypic.com/34yclf9.gif

http://i62.tinypic.com/34rsuhg.gif

http://i62.tinypic.com/2cpvorb.gif


Dr. Ventrice tweeted this so credit to him.

http://i57.tinypic.com/e0sih2.png

[HURRICANELONNY]

At least it will be sustained cooldown throughout the week.

South Florida will be mainly influenced by expansive Canadian
surface ridge...whose center will remain anchored over the
Mississippi Valley through the long term period. Aforementioned
shortwave trough will deepen and close off over New England...and
also become nearly stationary during this time. For South
Florida...these features will translate to persistent north-northwest
flow...with moderate cold air advection...likely through the end of the work-
week

[gatorcane]

Looks like a prolonged period of below normal temps for Florida, doesn't look record breaking in terms of how cold it will get but the duration looks impressive. The latest ECMWF keeps the below normal temps through almost 10 days with dry NW flow and periodic reinforcing cold fronts through the period.

[TheStormExpert]

Looks like a prolonged period of below normal temps for Florida, doesn't look record breaking in terms of how cold it will get but the duration looks impressive. The latest ECMWF keeps the below normal temps through almost 10 days with dry NW flow and periodic reinforcing cold fronts through the period.

Yeah impressive for sure especially since the last 2-3 Decembers have been rather mild here in S. FL. This is also the first prolonged cool/cold snap since back in mid-January! I'll take it now over then since it is the holiday season and cool/cold weather usually puts me into a cheerful mood!