South Florida turning more tropical?

[chinandega81 176]

Hello,

 

As many people know, South Florida has been much warmer than usual over the past few years (summers, winters). Lately there have been many record high lows and high daytime highs. 

 

I have seen graphs showing a general warming trend in Miami over the past 100 years or so...it averages out to 2 or 3 degrees warmer than what it used to be in the early 1900s.

 

My question is, do you think this is just because of cyclic patterns of warm and cool periods coinciding with urbanization? Or is this a long term trend? I have read about frosts being somewhat frequent at Fairchild in the 70s and now they are very rare if any even occurr in a winter.

What are your experiences in South Florida regarding this warming?

I have noticed many bread fruit trees in my neighborhood, but I also know they grow fast so they probably haven't been around for too many years.

 

Please share your thoughts or experiences in the garden and weather world from South Florida, I would love to hear them.

[kinzyjr 3,777]

I don't think this trend is exclusive to South Florida.  Inland Central Florida has had some mild winters, but even the bad ones like 2010 haven't been as bad as the 1980s, 1977, 1962, etc. 

I'm certain that urbanization has played a role in mitigating the effects of freezes in all urban areas.  If a palm is tight up against a block building, it gets extra heat from the building as well as wind protection during advective events.  This may alter the climate conditions for that little 5x5 slice of paradise enough for out of the ordinary plants to survive.  It certainly does for Adonidia and Ptychosperma in Lakeland as well as the I-Drive coconut and other plantings in the busiest parts of Orlando.  It's possible the effect is even stronger down your way since you tend to get more direct sun due to latitude.

There are certainly repeating patterns with weather.  Take for example, 1890s freezes + 1980s freezes.  Whether the overall energy in the system and urbanization is enough to raise the low temperature during an event like these remains to be determined from my point of view.  As an example, the freeze in 1985 dropped us to 20F for an all-time low in January.  Would urbanization and extra energy in the global weather systems be enough to keep us at 21F?  It's a question that myself and @palmsOrl talk about frequently, and one I hope to never have to answer concretely.

A few documents that may spark your or other participants' interest:

Timeline: http://flcitrusmutual.com/render.aspx?p=/industry-issues/weather/freeze_timeline.aspx

Also see attached PDF.

Florida_Citrus_Freezes_and Polar_Anticyclones_in_the_Great_Plains.pdf

[chinandega81 176]

Thanks for the link. Interesting how the freezes seem to happen once a decade until the 80s where there were several and then they all stopped. 

Here in SoFlo I notice some rather large Breadfruit tree when years ago I remember only seeing small ones (maybe 10 feet tall) and now there are several that area easily two stories tall. I know they grow fast and we have had freakishly warm weather these past few winters so that may be a factor as well. But I would love for a more equatorial tropical climate to envelope South Florida and hopefully more tropical like weather into Central Florida. I don't know if the use of tropicals in the Orlando area now is because they are just more available for people? Or because the weather is actually less cold in the winter. 

On a side note, I feel like with Florida trending warmer, we should look at what native is. Most of the native vegetation occurring here came from the north. If the peninsula came from the south more tropical vegetation would have migrated here. I see way too many Live Oak trees throughout the state and I don't see why they are so over planted....make FL look unique and diverse with tropicals and subtropical trees....we don't need to look like Virginia at this low lattitude. We have so many other choices for flowering and fruiting shade trees and palms. Ok rant over lol !

[Silas_Sancona 4,393]

1 hour ago, chinandega81 said:

On a side note, I feel like with Florida trending warmer, we should look at what native is. Most of the native vegetation occurring here came from the north. If the peninsula came from the south more tropical vegetation would have migrated here. I see way too many Live Oak trees throughout the state and I don't see why they are so over planted....make FL look unique and diverse with tropicals and subtropical trees....we don't need to look like Virginia at this low lattitude. We have so many other choices for flowering and fruiting shade trees and palms. Ok rant over lol !

Actually,  most of the  -more recent, ( timescale wise )-  "native" plants there in South ( and, to a lesser extent, coastal south Central FL, areas further north / inland. ) originated in the Caribbean Basin, esp things like the region's native Orchids, Bromeliads, and specific Ferns/ cacti of more tropical Genera/origins. 

As i'm sure you have researched, when the FL. peninsula was much more exposed than it is presently, -and the climate was cooler- native flora resembled what you see here in the Southwest/ California, aka scrubby Chaparral and Oak woodland.. Most famous " link" is the FL/ CA. Scrub Jay.. Same basic bird/ different sub species, which once ranged from CA around the Gulf of Mexico to FL. Remaining vestiges of this "old" habitat exist on the Lake Wales Ridge, which was pretty much the only part of Florida that wasn't repeatedly underwater.  When sea levels dropped, thats when things like the Oaks..perhaps stuff like Red Maple, other "northerly" things started colonizing the state..

Now that things are getting warmer again, that " Caribbean-type " vegetation will keep creeping further and further north, only being slowed/ haulted by repeated frost/freezes. ( Mangroves and "coastal" things like Sea Grape, Railroad Vine, Beach Bean would be the first "tropical pioneers" to move north into new territory.. ) Real "Equatorial/ Amazon-type" natives will likely take a while to make it that far north, having to first hop scotch across the Caribbean Basin from Venezuela Guyana, Suriname, and French Guiana again. ..as i'm sure they have done in the past, then trying to establish themselves again in the state, if it is still above water at that time....

As far as using Northern- native trees like Live Oak/ Red Maple, in South FL. ( or even Coastal S. Central FL, ie: Ft. Meyers/Venice, Sarasota/Bradenton, or St. Pete ).. Never understood that either. Would be the absolute last considerations on a list of choices.  lol.

 

[chinandega81 176]

I wonder if California was wetter back when it was more similar to Florida? 

What I don't understand is why more tropicals from Central and South America have made it to Carribean Islands, but not Florida. It seems like if things could jump between islands they could make it to Florida easily with the Gulf Stream. I hope Florida becomes more tropical...I feel like if we were an isthmus connected to Cuba or the Yucatan we would have way more tropical plants and animals here.

It's a shame that FL introduced some nasty exotics and now the state is ultra paranoid about non-natives. Not all of them are like Brazilian pepper or Australian Pines or Maleluca.  I think similar latitude locations in the Southern Hemisphere are more tropical due to their land connection towards the equator...Miami is close to Asuncion, Paraguay and they seem much more tropical than we do (minus the beaches).

Central Florida would be like Northern Argentina or southern Brazil which are rather tropical as well. 

I wonder if North Florida has seen a change to...for example, bananas not freezing back some winters? I saw someone post here once that Ocala winters were now more similar to Orlando winters, which would be a great sign if true!

[Silas_Sancona 4,393]

20 minutes ago, chinandega81 said:

I wonder if California was wetter back when it was more similar to Florida? 

What I don't understand is why more tropicals from Central and South America have made it to Carribean Islands, but not Florida. It seems like if things could jump between islands they could make it to Florida easily with the Gulf Stream. I hope Florida becomes more tropical...I feel like if we were an isthmus connected to Cuba or the Yucatan we would have way more tropical plants and animals here.

It's a shame that FL introduced some nasty exotics and now the state is ultra paranoid about non-natives. Not all of them are like Brazilian pepper or Australian Pines or Maleluca.  I think similar latitude locations in the Southern Hemisphere are more tropical due to their land connection towards the equator...Miami is close to Asuncion, Paraguay and they seem much more tropical than we do (minus the beaches).

Central Florida would be like Northern Argentina or southern Brazil which are rather tropical as well. 

I wonder if North Florida has seen a change to...for example, bananas not freezing back some winters? I saw someone post here once that Ocala winters were now more similar to Orlando winters, which would be a great sign if true!

There's a book i have somewhere that dove into the pre- historical climate of CA and discusses how, when the Central Valley was a shallow sea, palms, of some sort, a relative of Avocado, and Ficus? i think? grew in the state, among other plants considered tropical by many. Iguana, Boa constrictor and Jaguar are all also recorded in the state's fossil history ..so yes, at one time, CA had a similar climate to what you might see now in southern Sonora Mexico, say around San Carlos/ Guaymas and Alamos/ El fuerte near the Sonora/Sinaloa border. Crocodile, or a relative of the American Croc, whose northern boundary is somewhere near San Carlos, used to roam swamps around Tucson.. Think about that.. Kind of crazy when you see the landscape as it exists today..
The Chaparral of Southern CA, closer to the coast, also had such "Desert" plants as Ocotillo and some other stuff mixed in with the plants that make up that habitat presently. Makes sense considering all of that part of CA is a remnant part of Baja, which itself is the torn off, and north-shifted, western edge of mainland Mexico.

As far as Florida is concerned, agree that if the peninsula were connected to the Yucatan you'd see more direct exchange of species -both plants and animals, like what happened when the isthmus of Panama formed. At the present, most stuff that settles -then begins- the establishment of Florida is brought in by birds, or is blown in during Hurricanes. If connected to Central America..or even S. America, more Mammals capable of distributing the seed of other plants in more tropical Genus would have been able to move things into the region easier.  For all we are aware, some animals capable of getting to FL from the islands did make it, but were wiped out when humans moved in. Other stuff would have to move east, from Texas and the eastern side of Mexico to reach FL. 

Land mass size / surrounding ocean influence, etc  also plays a part.. If what parts of Florida are currently 10-200Ft underwater presently  had stayed above sea level, without interruption, you'd likely see quite a bit more diversity.. Same if the state had some steep sided Mountains. As has been discussed before N. America kind of lost out on the "extant of Tropical climate" game from the start.. S. America has no connection to Antarctica, and much more Ocean in between to modify intrusions of polar air.. Here, cold air just runs right down the plains into the Gulf of Mexico, or the southern States and FL.

If you track things like Birds or Insects, you can see a pattern between what species, from more southerly tropical locations ( ie: the Caribbean..maybe even the northern coast of S. America in Florida's case ) are edging up into the state and beyond as things trend warmer.. American Flamingoes are a good example, showing up along the panhandle of FL, and nearby Alabama so often in the last few decades.. The Metallic Green Orchid Bee that found it's way to S. FL. is another talked about example. can be found in Orlando now. ..Is also colonizing the southern tip of Baja currently, and eventually may show up in CA..  Things with wings can get around the easiest, and will often be most sensitive to warm/ cold temperature exposure, esp. in a new location. 

  Again though how far north something will get will depend on it's tolerance to cold. Some things ( the ever present Grackles here are a great example ) are quite hardy for originating in the Tropics. Other things may be much more particular, the "Goldielocks" of their kind ..or simply don't move around much. ( IE: several of the Caribbean islands have endemic sp. of Oriole, native to specific islands, but nowhere else.. ) No doubt that would be different, i think, if things were more physically connected.

[chinandega81 176]

I'm glad you brought up birds. Have you heard of the oropendola? It is a bird in Central America and the Carribbean. I have always wondered why it isn't present in Florida. We have the same vegetation it nests and lives in in Central America. I love it's call. I have tried to ask birders if there have been sighting of them in Florida but most people don't reply or aren't aware of it so I suppose that's a no. But if they made it to Cuba from say the Yucatan I don't see why they couldn't make it to the Keys from Cuba. Especially with the help of hurricanes.

What is called native in SoFlo is just what has been weedy historically. I have Live Oaks pop up that I have to pull out along the fence line constantly. I also have Carob trees (nice but they colonize areas) which is non-native.  I have also seen umbrella trees, gumbo limbos, pop up a lot. They may as well be considered native by this point since they are ubiquitious and not going anywhere anytime soon.

I see how at home many species here are like iguanas which thrive. They are native to the caribbean...why couldn't one had made it here earlier and be a native here? They don't overrun their native areas because people hunt them there...here they aren't hunted so people say they are an out of control exotic. 

Even in Central America if you go to undeveloped rural land in the Pacific lowlands, the landscape doesn't look tropical. It is decidious and nothing special. The difference is in Central America cities and towns, native AND non-native tropicals are everywhere. I think if the US colonized one of these countries and implemented their native plants only...the landscape would be planted with bland natives much like SoFlo is now.

 

In Socal I notice the government plants non-natives, probably because they aren't as invasive there as in Florida. The good soil there also helps everything look great. Even Malelucas and Brazilian pepper look good. Hong Kong Orchids and Queen Palms look great as well. I suppose water is the main challenge though.

 

If only local governments sought out more exotics....we have enough natives everywhere...

[Silas_Sancona 4,393]

10 minutes ago, chinandega81 said:

I'm glad you brought up birds. Have you heard of the oropendola? It is a bird in Central America and the Carribbean. I have always wondered why it isn't present in Florida. We have the same vegetation it nests and lives in in Central America. I love it's call. I have tried to ask birders if there have been sighting of them in Florida but most people don't reply or aren't aware of it so I suppose that's a no. But if they made it to Cuba from say the Yucatan I don't see why they couldn't make it to the Keys from Cuba. Especially with the help of hurricanes.

What is called native in SoFlo is just what has been weedy historically. I have Live Oaks pop up that I have to pull out along the fence line constantly. I also have Carob trees (nice but they colonize areas) which is non-native.  I have also seen umbrella trees, gumbo limbos, pop up a lot. They may as well be considered native by this point since they are ubiquitious and not going anywhere anytime soon.

I see how at home many species here are like iguanas which thrive. They are native to the caribbean...why couldn't one had made it here earlier and be a native here? They don't overrun their native areas because people hunt them there...here they aren't hunted so people say they are an out of control exotic. 

Even in Central America if you go to undeveloped rural land in the Pacific lowlands, the landscape doesn't look tropical. It is decidious and nothing special. The difference is in Central America cities and towns, native AND non-native tropicals are everywhere. I think if the US colonized one of these countries and implemented their native plants only...the landscape would be planted with bland natives much like SoFlo is now.

 

In Socal I notice the government plants non-natives, probably because they aren't as invasive there as in Florida. The good soil there also helps everything look great. Even Malelucas and Brazilian pepper look good. Hong Kong Orchids and Queen Palms look great as well. I suppose water is the main challenge though.

 

If only local governments sought out more exotics....we have enough natives everywhere...

Those drier, "deciduous" parts of Central America are actually part of the overall Tropics.. and, at least according to research i have read, are said to contain wider diversity than what can be found in the "true" tropics, ie: hugging the equator/ Amazon basin, at least in the Americas.. There are also parts of the highlands in, at least the northern part of Central America and Eastern Mexico, which contain numerous " Temperate"  species/Genus of trees, Quercus ( Mexico is supposedly the center of diversity for them ), Magnolia, and Liquidamber, aka Sweetgum are major examples.. 

Have heard of that Bird species.. West side of Mexico contains a similar looking bird,  Caciques (  same family i believe ) but the northern most birds of one sp. are only encountered in Southern Sonora, despite having a habitat preference that would allow them to survive here in AZ ( or in CA ) and nothing from keeping them from expanding their range north, except  maybe cold tolerance..  In both cases, it might just be a matter of time before one or the other becomes the next newsworthy species to appear in either state. Purplish Backed Jay, a more tropical  relative of Blue Jays, were recently documented not too far south of the international border near Nogales..  Another type of Jay, from the same part of southern Sonora, is currently expanding it's range across San Diego County after escaped birds in Tijuana established a breeding colony near the border years ago.  Then of course, there are the Parrots of Southern California.. a few of which originate in Western Mexico. 

As far as Iguanas.. possible an extinct distant relative exists in the fossil record in FL.. depending on how long they took to colonize the Caribbean basin/ reach FL.. if the state was above sea level and it was warm enough at the time they washed ashore. May have died out when the region cooled/ sank under the sea again.   As for now,  I say, live with them.. If some can't, the meat is supposedly quite tasty, nutritious, and fetches a good price per pound.. And no, lol.. pretty much impossible to stop them from moving north ..if the climate suites their expansion.

As far as invasives, have been hearing that Brazilian Pepper is being ax-ed in CA, essentially for the same reason it was banned in FL.. True, might spread quite as much there compared to FL. but.. a nasty tree regardless, Same w/ Carrotwood.  Gumbo Limbo is one of those Caribbean basin native trees that found it's way to FL. via migratory birds that love/ spread the seed.

[palmsOrl 1,574]

A good portion of South Florida already has a tropical climate, while none of the southern portion quite makes it to the tropical latitudes, even the Keys.

I wouldn't doubt that major urban areas already within the tropical climate zone are getting even more "tropical" due to the existing urban heat island effect and increasing urban sprawl.  Locations just barely out of the tropical climate zone, like Port Charlotte, Fort Myers and Stuart might end up tropical at some point with more urban development.

[palmsOrl 1,574]

On 7/15/2020 at 12:49 PM, kinzyjr said:

I don't think this trend is exclusive to South Florida.  Inland Central Florida has had some mild winters, but even the bad ones like 2010 haven't been as bad as the 1980s, 1977, 1962, etc. 

I'm certain that urbanization has played a role in mitigating the effects of freezes in all urban areas.  If a palm is tight up against a block building, it gets extra heat from the building as well as wind protection during advective events.  This may alter the climate conditions for that little 5x5 slice of paradise enough for out of the ordinary plants to survive.  It certainly does for Adonidia and Ptychosperma in Lakeland as well as the I-Drive coconut and other plantings in the busiest parts of Orlando.  It's possible the effect is even stronger down your way since you tend to get more direct sun due to latitude.

There are certainly repeating patterns with weather.  Take for example, 1890s freezes + 1980s freezes.  Whether the overall energy in the system and urbanization is enough to raise the low temperature during an event like these remains to be determined from my point of view.  As an example, the freeze in 1985 dropped us to 20F for an all-time low in January.  Would urbanization and extra energy in the global weather systems be enough to keep us at 21F?  It's a question that myself and @palmsOrl talk about frequently, and one I hope to never have to answer concretely.

A few documents that may spark your or other participants' interest:

Timeline: http://flcitrusmutual.com/render.aspx?p=/industry-issues/weather/freeze_timeline.aspx

Also see attached PDF.

Florida_Citrus_Freezes_and Polar_Anticyclones_in_the_Great_Plains.pdf 874.76 kB · 2 downloads

Yeah, I know for a fact that answering that concretely would be real bad news for a number of folks.

Fortunately, most Central Florida freeze events are radiational and the urban heat island effect goes really far in attenuating these events. 

There is, however, evidence that this urban heat island effect exerts little to no effect on minimum temperatures at the urban stations versus in rural surrounding areas.   The example I am thinking of is the 2018 freeze event, specifically in the Orlando area.  But it is possible that during extreme record setting advective events like 1989, that an large urban area would exert more thermal inertia (versus typical, less severe freezes) and keep minimum temperatures 1-2F higher than surrounding areas.

Has Houston or New Orleans experienced a freeze that was both advective and had the record breaking severity of a 1980s freeze in the past few years?  If so, data from that event could be useful.

Thank you for posting that link Jeremy!

[Jeff985 620]

6 minutes ago, palmsOrl said:

Yeah, I know for a fact that answering that concretely would be real bad news for a number of folks.

Fortunately, most Central Florida freeze events are radiational and the urban heat island effect goes really far in attenuating these events. 

There is, however, evidence that this urban heat island effect exerts little to no effect on minimum temperatures at the urban stations versus in rural surrounding areas.   The example I am thinking of is the 2018 freeze event, specifically in the Orlando area.  But it is possible that during extreme record setting advective events like 1989, that an large urban area would exert more thermal inertia (versus typical, less severe freezes) and keep minimum temperatures 1-2F higher than surrounding areas.

Has Houston or New Orleans experienced a freeze that was both advective and had the record breaking severity of a 1980s freeze in the past few years?  If so, data from that event could be useful.

Thank you for posting that link Jeremy!

January 2018 was an advective freeze in Houston and it was the coldest on record since Hobby airport became Houston’s official weather station in 1990. At hobby airport the low was 19 degrees. In the western suburbs it was 1-2 degrees colder. In the core it the city (the UHI) it was 20-21 degrees and the bay front was 21-23. UHI had a 1-2 degree bump. During radioational freezes it more like 2-4 degrees warmer than hobby and 5-7 degrees warmer than the western suburbs. 

[kinzyjr 3,777]

2 hours ago, palmsOrl said:

There is, however, evidence that this urban heat island effect exerts little to no effect on minimum temperatures at the urban stations versus in rural surrounding areas.   The example I am thinking of is the 2018 freeze event, specifically in the Orlando area.  But it is possible that during extreme record setting advective events like 1989, that an large urban area would exert more thermal inertia (versus typical, less severe freezes) and keep minimum temperatures 1-2F higher than surrounding areas.

I'm up in the air on how much of an effect it can or could have.  Looking at weather records for the NOAA stations, there is very little difference between even the most protected areas and the inland areas for the 1890s and 1980s freezes.  2018 would be a decent trial run if the weather records weren't so divergent on what the actual temperature was in my area. 

I'll summarize for 2018 below, but the rest of my analysis is on the Make Your Own Zone Map thread:

https://www.palmtalk.org/forum/index.php?/topic/6179-make-your-own-zone-map/&do=findComment&comment=939342

The possible readings were 24F (AccuWeather), 25F (WeatherUnderground), and 28F (Weather.com) from the major weather sources.  There are no NOAA weather stations that report weather downtown.  Both LAKELAND 2, FL US (GHCND:USC00084802) and LAKELAND LINDER REGIONAL AIRPORT, FL US (GHCND:USW00012883) record at or near the Airport.  My personal weather station recorded 28.2F.  Several others in the area recorded 28.x, where the x could be anything from 0-9.  If my reading was the only 28, I'd have trashed the reading and the weather station.

I wish I knew how Weather.com got that number.  If they have a weather station elsewhere in the city that recorded a 3-4 degree difference, that would at least give some credence that a sheltered environment could mitigate at least some of the damage by an advective freeze.

2 hours ago, Jeff985 said:

January 2018 was an advective freeze in Houston and it was the coldest on record since Hobby airport became Houston’s official weather station in 1990. At hobby airport the low was 19 degrees. In the western suburbs it was 1-2 degrees colder. In the core it the city (the UHI) it was 20-21 degrees and the bay front was 21-23. UHI had a 1-2 degree bump. During radioational freezes it more like 2-4 degrees warmer than hobby and 5-7 degrees warmer than the western suburbs. 

Thank you for that report, Jeff.  Going into this my guess was a 1F bump or less in town, but the effect might be greater as you indicated.

Edit:

I did find a station with a slightly higher reading range than I originally listed for the January 2018 event:

 

[chinandega81 176]

The other question is....what is the difference in an open space like a lawn in the middle of the urban heat island vs a lawn in the suburbs vs an open field in the country. 

I believe that unless you have plants in sheltered locations in the middle of a concrete jungle, the heat island effect is minimal. Most people have lawns in neighborhoods which cool off quicker even is amid a major metropolitan area.

I have also noticed when SoFlo gets a cold snap (usually when it's cloudy and highs are in the 50s) the temperatures are virtually the same at the beaches,  downtowns, the airports and the suburbs. Even the difference between the west coast and central FL is minimal. If this cloud cover and cold last for a few days there isn't much residual heat in the concrete left to do much warming. 

I think if there is just one calm, still cold night the UHI effect helps in urban areas but if it is advective, the help is much less. Maybe a degree or two or more dependent on one's individual yard and overhead canopy.

[Jeff985 620]

52 minutes ago, chinandega81 said:

The other question is....what is the difference in an open space like a lawn in the middle of the urban heat island vs a lawn in the suburbs vs an open field in the country. 

I believe that unless you have plants in sheltered locations in the middle of a concrete jungle, the heat island effect is minimal. Most people have lawns in neighborhoods which cool off quicker even is amid a major metropolitan area.

I have also noticed when SoFlo gets a cold snap (usually when it's cloudy and highs are in the 50s) the temperatures are virtually the same at the beaches,  downtowns, the airports and the suburbs. Even the difference between the west coast and central FL is minimal. If this cloud cover and cold last for a few days there isn't much residual heat in the concrete left to do much warming. 

I think if there is just one calm, still cold night the UHI effect helps in urban areas but if it is advective, the help is much less. Maybe a degree or two or more dependent on one's individual yard and overhead canopy.

Suburbs vs inner city is a tough one to answer. Inside the I610 loop there are probably over 100 weather stations. Most of them showed a low of 20. There were a few that said 21.  Katy, a western suburb with the same latitude was 17-18. Alvin, a suburb south of Houston was 19. League City, suburb south of Houston, still fairly urbanized and closer to the water bottomed out at 20. Northern suburbs were all in the teens. Going east you never completely leave the urbanization unless you get on a boat. At the bay front weather stations were 21 (northern Galveston bay) - 23 (southern Galveston bay). Galveston had a low of 25 with some weather stations recording a low of 27. A few royals and foxtails there died, but most survived. It’s hard to say how much of the temperature variation was due to urbanization since these spots are so far apart. I think the best indicator would be UHI vs Katy since they’re at the same latitude and neither are near water and are about the same elevation. The only difference I can see between the two is urbanization and the difference was about 2 or 3 degrees. If the cold had lasted much longer, I would agree that the gap would have shrunk and eventually the temperatures would have equalized. Hope this helps. 

[TampaPalms 32]

One thing I noticed that hasn't been discussed is Florida becoming drier (and wetter)? This of course would have affect on the fauna of Florida. Central and South Florida seem to be getting wetter while North Florida is getting a lot drier according to research.  

 

 

[kinzyjr 3,777]

1 hour ago, TampaPalms said:

One thing I noticed that hasn't been discussed is Florida becoming drier (and wetter)? This of course would have affect on the fauna of Florida. Central and South Florida seem to be getting wetter while North Florida is getting a lot drier according to research. 

From the look of it, once they factor in 2020, things should be a little closer to the old average. 

[Xenon 1,364]

I made this map mostly to see which parts of Houston did not record a freeze in the early season cold wave on the morning of Nov 13, 2019 (which ended up being the coldest reading of the season).  North and west of town saw 27-29F while south and southeast Houston only saw a light frreze with most readings less than 2 degrees below freezing.  In town, the SW Loop around the TMC and Museum District had the warmest readings (no freeze). This was also the only area away from the bay that had significantly green queen palms after the Jan 2018 freeze. 

[chinandega81 176]

Is the 32 to 33 degree area the typical warmest spot in Houston? I would have assumed it would have been the urban core downtown area.

What are the annual coldest recorded temps in downtown Houston? Mid 20s? Or does it fluctuate wildly?

I'm just wondering if plumeria, mango, royal palms, bananas could make it through most winters there with some reasonable protection in the warmest heat island? I know Galveston has a lot of tropicals but I assume with global warming Houston will soon be a few degrees warmer and a lot more tropical looking. 

[Jeff985 620]

1 minute ago, chinandega81 said:

Is the 32 to 33 degree area the typical warmest spot in Houston? I would have assumed it would have been the urban core downtown area.

What are the annual coldest recorded temps in downtown Houston? Mid 20s? Or does it fluctuate wildly?

I'm just wondering if plumeria, mango, royal palms, bananas could make it through most winters there with some reasonable protection in the warmest heat island? I know Galveston has a lot of tropicals but I assume with global warming Houston will soon be a few degrees warmer and a lot more tropical looking. 

The entire area inside the i610 loop has a strong UHI. Average annual low would be around 30f. Hobby airport average low 1989-2019 is 28, and inside the loop is consistently a couple degrees warmer than the airport. The area you’re asking about (the med center, and museum district) is the warmest part of the UHI. Yes, most winters bananas, mangos, plumerias, royals do just fine. It’s just those freezes that come every couple of decades that wipes them out. We just had one of those in January 2018. However where I live, bay front, plumerias survived that event (22f). 

[chinandega81 176]

Well if it takes every couple decades to do major damage I would think tropicals should be widely planted and sold in this area. The trend is stronger warming long term...and if the average annual low is 30 that is totally doable for most of the borderline tropicals. Is there a thread documenting current tropicals in the Houston area? I know I have seen pics from years ago of a a few random plantings in the area...but it seems like there should be more now.

 

[Jeff985 620]

14 minutes ago, chinandega81 said:

Well if it takes every couple decades to do major damage I would think tropicals should be widely planted and sold in this area. The trend is stronger warming long term...and if the average annual low is 30 that is totally doable for most of the borderline tropicals. Is there a thread documenting current tropicals in the Houston area? I know I have seen pics from years ago of a a few random plantings in the area...but it seems like there should be more now.

 

This is the most recent thread highlighting Houston’s tropicals. This is only about a year and a half after the 30 year low we experienced in January 2018 so there’s not as much in the thread as there would have been before that freeze, or there would be now. A lot of tropicals are being replanted. Foxtails are becoming pretty popular, as are a. cunninghamiana, plumerias, and I’m seeing Norfolks being replanted in some areas. I’ve planted a royal and have two more in pots waiting for them to get a little bigger before planting them. Availability is an issue. There’s a lot of stuff I’d like to try, but they’re not available here. 

[Xenon 1,364]

5 hours ago, chinandega81 said:

Is the 32 to 33 degree area the typical warmest spot in Houston? I would have assumed it would have been the urban core downtown area.

What are the annual coldest recorded temps in downtown Houston? Mid 20s? Or does it fluctuate wildly?

I'm just wondering if plumeria, mango, royal palms, bananas could make it through most winters there with some reasonable protection in the warmest heat island? I know Galveston has a lot of tropicals but I assume with global warming Houston will soon be a few degrees warmer and a lot more tropical looking. 

Just due southwest of downtown is the warmest pocket. The urban core (roughly defined by I-610 on the map) in general very rarely records temps below high 20s. It likely did not drop below 25F in this area from 1997-2016 (almost 20 years). It's fairly common for no freeze to occur at all, parts of urban Houston did not record a freeze for most of the late 90s, 2000s, 2012, 2013, 2015, 2016, and the last two winters. Tree sized plumeria, fruiting mangoes, foxtail palms, etc could all be found in this area in the 2000s. 2010, 2011, and 2014 did some damage with readings in the mid-upper 20s but some mature foxtail palms planted in the 2000s managed to persist until being wiped out in 2017.  This area is also the only area away from water that still has many old pygmy dates (planted in the 2000s) and there are also a few old majesty palms.  It's pretty much zone 9b/10a until a massive advective freeze (like the double whammy of 2017 and 2018) negates/minimizes the urban effect and makes complete carnage of the zone 10 stuff. Tropicals are readily available and pop up all the time if you keep an eye out for them, but the dominant landscape theme is still deep southern live oak, magnolia, crepe myrtle etc.  

[chinandega81 176]

Great Houston pics in the other thread. It seems like Areca palms would do well in the warmest areas of Houston if temps rarely go below the upper 20s...especially on the south side of a building.

I suppose one thing working against Houston tropicals are the lack of concrete structures. It seems like a lot of wooden frame homes...which obviously don't hold in heat like florida cinder block and stucco. 

In South Florida there seems to have been a steading warming this past century...anecdotally people talk of somewhat frequent frosts annually in Miami and now they are very rare. Has Houston seen more anecdotal warming? As in, are the cold snaps less severe than they were 100 years ago? Even if by a few degrees?

[Jeff985 620]

1 minute ago, chinandega81 said:

Great Houston pics in the other thread. It seems like Areca palms would do well in the warmest areas of Houston if temps rarely go below the upper 20s...especially on the south side of a building.

I suppose one thing working against Houston tropicals are the lack of concrete structures. It seems like a lot of wooden frame homes...which obviously don't hold in heat like florida cinder block and stucco. 

In South Florida there seems to have been a steading warming this past century...anecdotally people talk of somewhat frequent frosts annually in Miami and now they are very rare. Has Houston seen more anecdotal warming? As in, are the cold snaps less severe than they were 100 years ago? Even if by a few degrees?

I’ve noticed that too. We still have the arctic invasions from time to time, but they have been less severe. Prior to 1990 the arctic blast would bring Houston down into the teens almost every decade. Sometimes even mid to lower teens. Looking at all the cold blasts from the last 30 years the warmer parts of Houston haven’t seen teens at all and the airport has only once with a low of 19. 

[Xenon 1,364]

11 minutes ago, chinandega81 said:

Great Houston pics in the other thread. It seems like Areca palms would do well in the warmest areas of Houston if temps rarely go below the upper 20s...especially on the south side of a building.

I suppose one thing working against Houston tropicals are the lack of concrete structures. It seems like a lot of wooden frame homes...which obviously don't hold in heat like florida cinder block and stucco. 

In South Florida there seems to have been a steading warming this past century...anecdotally people talk of somewhat frequent frosts annually in Miami and now they are very rare. Has Houston seen more anecdotal warming? As in, are the cold snaps less severe than they were 100 years ago? Even if by a few degrees?

Yes, all the tropical stuff does great for years or even a decade or two but there´s really no way to minimize a massive advective freeze except latitude and Houston is still at 29*N. It can go years without a freeze or only a light freeze and then one advective cold event in the low 20s = bye bye tropicals. The Houston metro population is over 7 million, trust me it's a concrete jungle here haha. The past 30 years have certainly been pretty mild, nothing like what happened in the 80s. I'm sure there were cycles of warm and cold in the 20th century. Houston also wasn't as big as it is now, so the artificial warming from urbanization is a contributing factor as well.  

Edited July 21, 2020 by Xenon

[Mr. Coconut Palm 1,173]

I have noticed significant warming in South Texas in general, and in particular along the coast and in the Rio Grande Valley over the last 30 years.  Back in the 1980's, when my family made 2 trips to the Rio Grande Valley and South Padre Island, I only saw 1 Queen Palm adjacent to the hotel we stayed in the old part of Brownsville near the river.  It was about 20ft. tall in overall height as I recall, and that is the ONLY remotely tropical looking palm or any tree for that matter that I ever recall seeing anywhere in South Texas back then, with the exception of one small Sea Grape about 3ft. to 4ft. tall in overall height at the Gladys Porter Zoo at the same time.  Now, there are Queen Palms planted all over South Texas, even as far north as the south side of Lake Conroe on the north side of Houston that I used to see frequently when driving through that area about 10 years ago, when I used to live in Bryan, and even a few planted by a guy I used to know in College Station, about an hour and a half northwest of Houston that survived for quite some time (maybe 8 to 10 years or more).  And now I have a mature producing Coconut Palm (Green Malayan Dwarf) in my front yard that is about 16ft. tall in overall height, and two others about 13ft. to 14ft. tall in overall height, and I live in Flour Bluff on the east side of Corpus Christi, Texas, near the water.  Back in the 1980's, you wouldn't even see a Coconut Palm anywhere in Brownsville or even South Padre Island, but I have heard there were some in the RGV back in the 1970's.  Now, there are mature 30ft. to 40ft. tall in overall height Coconut Palms with nuts on them in the RGV and South Padre Island, and large Sea Grapes there too.  I have a Sea Grape about 15 tall in overall height in my front yard that produces hundreds if not thousands of grapes every year now.  There are also Royal Poincianas here, (an utterly HUGE one in Brownsville that rivals any you might see in Ft. Lauderdale, FL), as well as LOTS of Ficus, and tropical fruit trees here in Corpus Christi, and throughout the RGV.  There are even tall mature Royal Palms at Moody Gardens in Galveston (at leasst the last time I was there).  I have noticed how winters used to average 6 or 7 freezes each winter at the airport in Corpus Christi, but now we can go for 1 to 2 years at a time without a single freeze at the airport.  I have a book on Padre Island National Seashore that was published by the by the government printing office for the National Park Service as I recall back in the early 1980's that said North Padre Island used to average at least one night each winter down to 29F.  Now, however, most winters, North Padre Island doesn't get below about 35F or 36F on the coldest morning, and has at least 10 in ground Coconut Palms growing there.

Also, as far as tropical species moving northward, back in the 1980's you would only see a few small Black Mangroves around the base of the causeway at South Padre Island and some at the Rio Grande Delta.  Now, the ones at the Rio Grande Delta are HUGE, and there are even mature seed producing Red Mangroves scattered out among the outer edge of the Black Mangroves, with one Red Mangrove across the river on the Mexican side of the border that appears to be about 25ft. + tall with a crown about 50 ft. wide!  The last time I was in Galveston about 10 years ago, I saw Black Mangroves there along the south jetty of Galveston Channel that appeared to be at least 6ft. or more tall.  Also, tropical species of fish, and birds are moving further north now too, as we frequently have more tropical Caribbean reef fish on our jetties here in the summer time, and a breeding colony of Green Parakeets (native to Tamaulipas, Mexico and the RGV) at both the Del Mar College West Campus and the old Catholic College on the west side of Corpus Christi now.  Also, my yard is full of Cuban Anoles now (about 5 times as many of them as the native anole) that have come in on nursery shipments to the local nurseries from South Florida, that are able to survive and breed here as our winters are significantly warmer than they used to be just 30 years ago.

John