Florida Weather

[NDG]

Now is the GFS that is showing very cold temps coming down to FL for Monday night, got to love the way the models flip flop, lol.

[northjaxpro]

This overrunning rain event has become quite significant across Northeast Florida as just under two inches of rain has been received at my locale since the rain started yesterday. The warm front has remained south of our area, which in turn has created the best isentrophic lift right across the Jax area. This is normally among the driest times of the season. so it is beneficial rain for sure. However, thankfully the rain is moving through at a good pace or else we would be looking at heavier rain totals. Since Sunday, I am approaching 4 inches of rain for the week.

More rain will move through later and will come to an abrupt end tonight as the cold front moves through bringing the first of two brief shots of polar air to come into the northern peninsula. As NDG astutely pointed out above, due to the fact that the Greenland Block has not established itself so far this winter, these arctic air masses won't be able to lock into place for a significant duration across the Deep South. The Arctic High axis will move off quickly east into the Western Atlantic, allowing for the return flow to moderate the temperatures quickly. So, these upcoming cold intrusions will be very brief. Thus, this progressive pattern will continue.

A 1036 mb Arctic High axis is expected to move rapidly east from the mid Missisissippi Valley starting late tonight and reach the Mid Atlantic region by Friday night. Friday will be a very chilly day with strong cold air advection and breezy North winds will bring bring temps near freezing inland areas tomorrow morning across the North Florida region. Highs tomorrow will struggle to reach 50 degrees if we are lucky. But, because the axis of the Arctic High in this instance will remain well north of this region, it does not set up the ideal scenario for radiational cooling conditions. The wind will likely stay up enough to prevent temperatures from getting into hard freeze criteria. Saturday morning lows will reach near or at freezing mark in the normally colder inland locations around the Big Bend and the Suwannee River Valley region. Meanwhile, by Friday night, the wind here in Northeast Florida should begin to veer to the northeast, with the center of the Arctic High approaching the Mid Atlantic region. This should keep the Jax area in the 32-35 degree range Saturday morning

I don't see any freeze potential with this first brief cold spell for central peninsula,although I would not be surprised to see some upper 30s in some spots down there in like Ocala and Brooksville the next 24-48 hours.

The next polar intrusion arrives late Monday and now the GFS has flip flopped from its earlier runs to now show a colder solution. There is still a bit of uncertainty currently of just how cold it will be early next week. So much depends on the trajectory of the next Arctic High coming in early week and how much the upper trough digs south.. The High axis will stay north of the area, but the axis could move more from the Southern Plains and east to the Tennessee Valley region, as the EURO was indicating a couple of days ago. If the latter scenario played out, it is possible that it may get colder early next week.

[NDG]

12z GFS and 12z Euro have finally come to a better agreement, almost identical, good to see the GFS back off some from its solution from the earlier 06z & 0z runs.
12z GFS MOS guidance right now shows low temps in the upper 30s in the Orlando area, but I am sure they will continue to go down with the 12z GFS raw numbers showing low to mid 30s for the Orlando area, which looks about right.
Glad to see those -10 deg C at H85 north of FL!

[TheStormExpert]

After early next weeks very brief cool down it looks like by the end of the week we will be back to usual above normal temps. that has been the normal so far this winter.

The NAO so far this winter (or since we've been getting cool/cold fronts) has been Positive(+) leading to very little cold air making it down the state, and when it does it is very short lived. This looks to continue probably through January at this point it looks.


The AO has been basically Positive(+) since late October with a quick trend towards Negative as of now but is expected once again to go back to Positive territory within the next week. Not a good sign if you want cool/cold air to stick around and become more frequent in appearance.


Lastly the PNA is expected to gradually head Positive(+) which is one of the many pieces needed in order to get and sustain any cool/cold air down here in Florida. Keeping my fingers crossed on this.


Let's just hope February brings a much needed pattern change for us Floridians sick of the above average temps. and summer like heat atypical of winter even here in Florida.

[northjaxpro]

Yeah, StormExpert, the AO for now is only slightly negative. I saw these indicices you posted above a short time ago. We need a strong positive PNA pattern to help send cold to the Deep South and the Florida peninsula as well. We have seen building heights in the vicinity of Alaska and the Gulf of Alaska to this point. A more favorable set up would be to see strong ridging across the Western U.S. However, as discussed earlier, another main element missing to help lock in a colder pattern in our region is ridging across Greenland. A blocking pattern over Greenland would enable these arctic airmasses that drop into the Eastern 2/3 of the U.S. from moving out too quickly and they stay can stick around for durations. So, unless we see the AO or NAO really start to tank, these shots of cold, if they come, will be quick to move through. A very progressive pattern right now.

[northjaxpro]

Just came from outside and folks it is cold out there this morning! Currently at 31.7 degrees and North winds gusting up to 25mph. Wind chill temps currently in the low 20s. Strong cold air advection is right on schedule and will probably drop a couple degrees more before temps crawl through the 30s all morning long. Max temps today only expected to reach 44-45 degrees despite sunshine and wind chill indices will make it feel even colder all day.

Inland areas will see another freeze tonight and early Saturday, then this brief arctic shot moves out as the Arctic High shifts into the Atlantic tomorrow and return flow will rapidly moderate temps this weekend. But, we have another shot of arctic air to pay us a visit late Monday into Wednesday of next week. This one may be even colder than the current one we are experiencing. GFS continues to trend a bit colder early next week. Posted that run on the Deep South Winter Weather thread earlier and it shows a potential freeze down into portions of the central peninsula on Tuesday morning.

[HURRICANELONNY]

I tend to disagree on AO/NAO. It's starting to tank and the NAO is slowly following.

http://www.cpc.ncep.noaa.gov/products/p ... x/ao.shtml

[northjaxpro]

Well, time will tell. Right now, the AO is only slightly negative. We will see if the O/NAO will start to really tank.

Also, temp now at 30.6 degrees at my locale.

[NDG]

I tend to disagree on AO/NAO. It's starting to tank and the NAO is slowly following.

http://www.cpc.ncep.noaa.gov/products/p ... x/ao.shtml

The link you provided the image has not been updated since Dec 23rd.
Here is the link to the current index & forecast which was just updated this morning, as you can see the AO has already tanked is forecasted to go up to at least slightly positive for the short term.
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif

The NAO has not tanked is not trending to tank any time soon as forecasted by the ensembles.
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif

[NDG]

With highs only in the mid 50s for the Orlando area I will not be surprised if highs only stay in the mid to upper 40s for next Tuesday all across central FL as indicated by the raw GFS numbers, the MOS is not showing this yet but they should be catching up to the raw numbers over the next couple of days, 30s for highs north FL with 50s to near 60 at the most for south FL, brrr!
Good thing that the Arctic High center axis will stay north of the Peninsula so winds at H925 should come onshore during the night Tuesday with moderating temperatures for the eastern half of central and south FL. Western central FL will have another chance of freezing temps Wednesday morning as it takes longer for cold air drainage to stop in that area as the surface High starts moving to our north east.

[HURRICANELONNY]

I tend to disagree on AO/NAO. It's starting to tank and the NAO is slowly following.

http://www.cpc.ncep.noaa.gov/products/p ... x/ao.shtml

The link you provided the image has not been updated since Dec 23rd.
Here is the link to the current index & forecast which was just updated this morning, as you can see the AO has already tanked is forecasted to go up to at least slightly positive for the short term.
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif

The NAO has not tanked is not trending to tank any time soon as forecasted by the ensembles.
http://www.cpc.ncep.noaa.gov/products/p ... .sprd2.gif

Oh. Now I see. Clicking the image shows the updated version. What a change. Maybe it'll flip back.

[FireRat]

HUGE temperature contrast across South FL tonight from west to east!

at around midnight Jan 4th:

Near 50 in Naples/Ft. Myers, 46 in Immokalee, 55 in the western edge of Plantation/Sunrise, 66 in Fort Lauderdale and 68 in Palm Beach. It seems the temp drops a degree per mile you head west in metro Broward and Palm Beach counties tonight.

[NDG]

Big temperature difference also in central FL between East coast &. West Coast.
Mid 60s in Melbourne area while the Tampa area is in the 40s, same thing could happen next Wednesday morning except temps will be a good 10-15 degrees colder.

[northjaxpro]

Good morning ! Wow is all I have to say after observing the latest model runs earlier this morning, especially the GFS. I am following the GFS closely for this next cold spell. This next arctic intrusion may be brief, but my goodness it will bring a powerrful delivery of air straight out of Siberia. This next arctic air mass potentially could be the coldest we have seen in many areas of the Deep South since 1996. Here in Northeast Florida, it has the potential to be the coldest here in Jax since 2003. If the GFS is right, this may have potential being a record breaking cold event

All week long I had been noticing how the GFS kept trender colder with this early week arctic shot, totally flip flopped to EURO's colder solution a cuple of days ago. GFS continued trending colder back on Thursday and that had really caught my attention. Then, I looked at the most recent runs this morning and WOW was I impressed with the values I am seeing with this next surge of arctic air coming into the region beginning on Monday.

I took at look at the latest GFS 850 millibar temperature values for Monday and I noticed -13 degrees Celsius all the way to near the Florida-Georgia border. Wow! I have not seen values that cold in years in these parts. One main thing to keep in mind is that we will have a fresh snowpack on the ground across the Mid Mississippi Valley, Tennessee Valley and Ohio Valley regions by Monday. This will help to keep this frigid air coming down from modifying at all. This makes me even more confident that records will be likely shattered all across the South and down into the North and possibly Central Florida region early next week.

. .So, when that arctic front moves through during the day on Monday across Northern Florida, temperatures are going to plummet. These 850 mb values support temps to fall drastcally all during the day Monday. Temps will likely fall all the way down into the mid-upper 30s by sunset Monday evening. Tuesday morning could be record breaking across much of the area. High temperaturs on Tuesday in Jax and much of North Florida will likely will not make it out of the 30s with arctic air well entrenched over the area at that time. Guidance is showing temps could fall into the 15-20 degree range across all of North Florida interior areas and even the low-mid 20s all the way to the coast. Central Florida could potentially see hard freeze conditions. Also, by Tuesday morning the 850 mb 0 degree C line will dive deep into the peninsula to about the I-4 corrior. Areas along that part of the state will likely see a significant freeze on Tuesday morning.

As for all of the South Florida, well Old Man Winter will finally give you guys a taste of cold air also on Tuesday morning before the arctic airmass moves out. Temps may drop to near freezing in interior South Florida around and to the west of Lake Okechobee according to GFS.

So, no question, we could be looking at a very impressive record cold spell early next week. Thankfully the progressive pattern locked in place will only have this frigid airmass around for only about 48 hours early next week. However, Old Man Winter will bring a harsh bite to our region though, so make any preparations needed to protect against the cold early next week.

More later.....

[NDG]

Northjaxpro, with all due respect I question the idea about a record breaking event for most of central and S FL for Tuesday and Wednesday mornings, at most it will tie records from the 2010 record lows, IMO.
I have been looking at the GFS raw & MOS forecast and I was questioning why with such low H85 temps forecasted the raw GFS has been for the most part only showing lows in the upper 20s to low 30s at the most across the I-4 corridor and with the latest MOS forecast (which is usually cold bias for C FL) only calling for a low of 32 for both Tampa & Orlando until I looked at the mid and upper level winds forecast by the GFS and Euro, they both call for SW winds in the mid to upper level winds during this event which may bring mid & upper level partial cloud cover for Tuesday & Wednesday morning from the active subtropical pacific jet.
By Tuesday night/Wednesday morning not only is the GFS calling for some cloud cover but as the Arctic High Pressure center stays north of the Peninsula for winds at H925 to start coming onshore from the Atlantic as which it usually keeps radiational cooling on tap at least for areas close to the Atlantic coast. So I am hoping that it comes true with its cloud cover forecast, otherwise it could turn out to be colder than 2010's event.
Edit: BTW, back in 2010's early Jan event 540 thickness values came all the way down to central FL and 0 deg C at H85 came all the way down to Miami, with this upcoming event both the GFS and Euro forecast thickness values to get down only to around 552 at the most.

[northjaxpro]

Hey NDG. You make valid points, but I have a gut instinct that the GFS may be closer to verifying when this is all said and done for this event. I just think that this time, The Arctic High axis, though staying north of the peninsula, will this time look to take a more favorable trajectory in helping to bring in a significant piece of the Arctic air to the North Florida area. The High center will move a bit more south this time moving in from the Southern Plains east to a postion around Southern MS by Tuesday morning. It will then move to the near the SC/NC Piedmont region by Wednesday morning. Plus the other factors I mentioned in my earlier post i.e.. fresh snowpack to our north etc...

We wll see. It is interesting trying to follow and forecast these extreme cold events that's for sure.

[NDG]

Hey NDG. You make valid points, but I have a gut instinct that the GFS may be closer to verifying when this is all said and done for this event. I just think that this time, The Artic High axis, though staying north of the peninsula, will this time look to take a more favorable trajectory in helping to bring in a significant piece of the Arctic air to the area. The High center will move a bit more south this time moving in from the Southern Plains east to a postion around Southern MS by Tuesday morning. It will then move to the near the SC/NC Piedmont region by Wednesday morning. Plus the other factors I mentioned in my earlier post i.e.. fresh snowpack to our north etc...

We wll see. It is interesting trying to follow and forecast these extreme cold events that's for sure.

I agree, it is interesting, is like a tracking a hurricane any deviations on the final track will make a significant differance if we see a historic freeze or not.
BTW, what do you think about last night's Euro? It showed higher heights than the GFS, it will be very strange for it to be so wrong within 72-96 hr forecast, which makes think that maybe the GFS might be too cold with its H85 forecast.

[northjaxpro]

Yeah, I saw that from EURO NDG. I really can't wait to see the next runs later on. However, the overall trend has been colder for this event and I am going to stick by the GFS solution for now.

BTW, it would be really something if GFS verifies and we have such an extreme cold event on the heels of one of the warmest Decembers we saw across this region ever!

[NDG]

We need to thank the subtropical Atlantic ridge which has found a home from the Lesser Antilles area west towards Cuba this winter so far.
First when the Euro showed the axis of the Artic Vortex get very close to FL back 3-4 days ago with H85 -20 deg C get down to central AL it was forecasting the Atlantic ridge to weaken but as time has gone by it dropped the idea of the Atlantic mid level ridge giving up much realty, otherwise the trough would had dug down much closer to FL and then we really would had been looking a record breaking event like in the 80s, IMO.

[northjaxpro]

Yeah that persistent ridge has been the story down here across the state seemingly forever lol... Bought many across the peninsula one of the warmest Decembers ever.

This upcoming upper level trough will amplify very deep to shift that ridge a bit more east away from Florida finally, although albeit will only for a brief time. When that trough lifts out and way by Thursday. However, I feel the ridge will be back over the area by the end of next weekend, unless the AO surprises us and goes negative for awhile longer, which I don't see that happening until we get to the start of February at the earliest.