So. FL. Micro climate created by proximity to GulfStream

[RFun]

On 4/9/2024 at 10:53 AM, sonoranfans said:

I will look at it without the gulfstream effect, then add it in.  The water off the east coast of florida  is far deeper than west coast waters.  I giant boiling pot of wter cools down slower than a small pot of boiling water.  Same is true for cooling, shallow lakes cool faster than deep ones.  The gulf side heats up and cools down faster than the east coast seasonally as the east coast ocean is a massive heat sink in winter and its true without the gulf stream and without wind..  In winter the water cools on top then sinks are warmer less dense water rises to the surface.  Yes the gulf stream has an effect but the depth of the water is 5-10x greater within 50 miles of the east coast compared with the west coast.  Now you can see why the west coast is hotter in summer and colder in winter, it just doesnt have the heat sink that the east coast has.  Now add in the wind and the fact that the gulf stream carries the cooled water north and replaces it with warmer water from the south and the ability to transfer heat from the air into the water jumps..  Being surrounded by water also has an impact of course, barrier island with 3 sides(one to the north) of water exposure as in Anna Maria Island Florida can no doubt make a difference, its typically warmer by a  few degrees than anywhere in St Pete on pinellas.  In 15 years Ive seen, the worst cold(28F) came from the north or North by northeast not the northwest.  Any air that comes northwest direction comes over the gulf.  All those places in north florida will see air coming over land which cools down faster in a cold front.  The ability of the gulf stream to carry cooling water north and replace it with even slightly warmer water can have a bigger effect in heat transfer than the still water model where the cooled water hangs around.

As a general rule of thumb, the East Coast of Florida is going to be milder than the West Coast of Florida.  There are always small microclimates that something like the USDA map is going to miss.  So, that always has to be kept in mind.  If Florida gets one of those once in a great while cold events, it's very likely to be warmer for the low in West Palm Beach than in Ft. Myers, all things considered.

[_nevi]

The southeast Florida coast seems to take on tropical monsoon (am) and/or tropical rainforest (af) characteristics compared to the rest of South Florida that is more tropical savannah (aw). Not sure if that is the Gulf Stream's doing, or some other factor.

[RFun]

On 4/15/2024 at 8:45 PM, _nevi said:

The southeast Florida coast seems to take on tropical monsoon (am) and/or tropical rainforest (af) characteristics compared to the rest of South Florida that is more tropical savannah (aw). Not sure if that is the Gulf Stream's doing, or some other factor.

Yes, that is true.  Far enough southeast in Florida (below around West Palm Beach) is where you start taking on more of the tropical monsoon characteristics.  So there, you really don't get much of a dry season that is notable.

[Looking Glass]

Down this way, we had a very wet (114”) awesome year last year, but most other years (48”) it is annoyingly dry at times.  Rain often comes in huge boluses.   It can not rain for a month, then rain 12 inches overnight, and suddenly there was 12 inches of rain for that month.  Sadly, it’s then bone dry after 2 days again and you’re firing up the irrigation.  

“Spring” is normally super dry and hot, and the rainy season is often disappointing.  I’m about 1-2 miles from the ocean, and often have to irrigate 3x per week and hand water heavily on top of that during the hot months sometimes.  The sand-soil here drains around 36 inches of water per hour, which is great for draining heavy flooding rains, but terrible for many tropical rainforest plants.  

You can grow some very tropical stuff here, but you need to pour on the water and have some shade protection from brutal clear skies.  Heavy amending of calcareous sandy soils is often needed too.    It’s no Hilo, Hawaii that’s for sure.   

[RFun]

3 hours ago, Looking Glass said:

Down this way, we had a very wet (114”) awesome year last year, but most other years (48”) it is annoyingly dry at times.  Rain often comes in huge boluses.   It can not rain for a month, then rain 12 inches overnight, and suddenly there was 12 inches of rain for that month.  Sadly, it’s then bone dry after 2 days again and you’re firing up the irrigation.  

“Spring” is normally super dry and hot, and the rainy season is often disappointing.  I’m about 1-2 miles from the ocean, and often have to irrigate 3x per week and hand water heavily on top of that during the hot months sometimes.  The sand-soil here drains around 36 inches of water per hour, which is great for draining heavy flooding rains, but terrible for many tropical rainforest plants.  

You can grow some very tropical stuff here, but you need to pour on the water and have some shade protection from brutal clear skies.  Heavy amending of calcareous sandy soils is often needed too.    It’s no Hilo, Hawaii that’s for sure.   

Of course, your version of "dry" is much different from most of the rest of the country.  Some parts of the country would be thrilled to get 12 inches of rain in one month.  For other parts, that would be WAY too much.  That's a ton of rain you get there (on average annually for Ft. Lauderdale) compared to most areas of the country.

[flplantguy]

8 hours ago, RFun said:

Of course, your version of "dry" is much different from most of the rest of the country.  Some parts of the country would be thrilled to get 12 inches of rain in one month.  For other parts, that would be WAY too much.  That's a ton of rain you get there (on average annually for Ft. Lauderdale) compared to most areas of the country.

Any transplant to florida has to learn the hard lesson on rainfall here. It looks great on paper. Its not. A tenth of an inch every night is a better rainfall pattern with less overall than florida gets, so its about more than just numbers but how they come together.  Or dont as the case may be in some places. Here it is feast or famine and the soils are crap, so it is not the paradise the tourism board claims it is. Look at the native plants and you can see the adaptation to this climate. Its why no one likes them, they are not lush enough. So yes, while people get jealous of the rains here its not all the at great without the soils and climate pattern to back it up. However it also leads to opportunity with the right plants. Jeff Marcus told me he cant grow certain species because of their rainfall and soil that florida can, so there are always trade offs.  I would still pick Hawaii myself.

[RFun]

4 hours ago, flplantguy said:

Any transplant to florida has to learn the hard lesson on rainfall here. It looks great on paper. Its not. A tenth of an inch every night is a better rainfall pattern with less overall than florida gets, so its about more than just numbers but how they come together.  Or dont as the case may be in some places. Here it is feast or famine and the soils are crap, so it is not the paradise the tourism board claims it is. Look at the native plants and you can see the adaptation to this climate. Its why no one likes them, they are not lush enough. So yes, while people get jealous of the rains here its not all the at great without the soils and climate pattern to back it up. However it also leads to opportunity with the right plants. Jeff Marcus told me he cant grow certain species because of their rainfall and soil that florida can, so there are always trade offs.  I would still pick Hawaii myself.

I think it's a very good climate (and soil) if you are growing the right plants for it.  The problem is that many are trying to grow the stuff that would be more suitable for somewhere like Hawaii.  But anyway, that rainfall average is impressive, regardless, compared to most places in the U.S.  What the soil is like there and what people are growing isn't the climate's fault.  Most places in the U.S. do have nuance to their average rainfall.  That would be natural.  But, many subtropical places in the Southeast do get a fairly steady amount throughout the year.

[Looking Glass]

12 hours ago, RFun said:

Of course, your version of "dry" is much different from most of the rest of the country.  Some parts of the country would be thrilled to get 12 inches of rain in one month.  For other parts, that would be WAY too much.  That's a ton of rain you get there (on average annually for Ft. Lauderdale) compared to most areas of the country.

This is true, everything is relative.  But as @flplantguy mentioned above, the way we get the rain is what matters most.  It’s inconsistent deluge conditions, followed by prolonged dryness.   It’s why many of the natural habitats here lean more desert-like than tropical forest.    Palms that do best here, are pretty drought tolerant, but also can survive the drought conditions that naturally wax and wane.  Cuban, Caribbean, and Native Palms can be slow, but man, they are worth it in these parts, as they are accustomed to our weather patterns. 

[RFun]

1 minute ago, Looking Glass said:

This is true, everything is relative.  But as @flplantguy mentioned above, the way we get the rain is what matters most.  It’s inconsistent deluge conditions, followed by prolonged dryness.   It’s why many of the natural habitats here lean more desert-like than tropical forest.    Palms that do best here, are pretty drought tolerant, but also can survive the drought conditions that naturally wax and wane.  Cuban, Caribbean, and Native Palms can be slow, but man, they are worth it in these parts, as they are accustomed to our weather patterns. 

But like I said, most areas do have quite the nuanced patterns of rainfall.  It isn't the climate's fault of what people choose to grow there (or their soil types).  Bottom line is that is an impressive average rainfall in that area compared to most places in the country.

[bubba]

Local observation: PB Country has two seasons. May-early November= Warm/ wet; November-May=Cooler/drier. Koeppen designates this in a sweeping variation of. Tropical Savanna/Tropical Monsoon.

Warm/ wet/ November-May is characterized by high humidity and threatening thunderstorms. You must also add in Hurricane Season, which can dramatically skew results. The standard guess for annual rainfall in SE Florida is 53 inches a year, 75% of which comes during the wet season (39.75 inches v 13.25 inches/ dry season).

The numbers  are “ ballpark” and subject to dramatic alterations. Specifically, I can remember a golf superintendent buddy of mine, who faithfully kept a rain gauge on a golf course located substantially west of the Florida turnpike and I-95. His buddy was also a golf superintendent, located at the Palm Beach Par 3, located directly on the ocean. They both kept rain gauges faithfully for at least that one year. The results were quite interesting. At the golf course located west of the Turnpike, that super recorded over 110 inches for that year. Parenthetically, during the same 12 month period, the golf superintendent located on the ocean recorded 33 inches. That year was particularly dry for the barrier island of PB, because in March of that year there was a super-coastal rainfall event, which dumped 22 inches of rain in what can only be described as a strange tropical event. It was strong enough to have some effect on the western location but in large order its effect on the western location was minimal (5-7 inches). The Breaker’s Ocean golf course was literally underwater for many days. However, the seabreeze that year was particularly strong and deflected all thunderstorm activity from reaching the ocean. Correspondingly, PB could only be properly categorized as dry.

By comparison, this year’s wet season has been very wet. Worst of all, the thunderstorm activity that is usually kept west of I-95, has frequently hit the coast. I believe someone described this as a “Super El Niño” and while I am not apt to flow with stereotypical representations, this would adequately describe this year.

The dry season is approximately the remaining 6 months and spreads roughly 13.25 inches over the timeframe, resulting in approximately 2.2 inches a month. Of this average amount, it may easily fall in one day during a frontal stall, making the rest of the month to seem  desert like. This is when we experience our respite from intense heat and humidity and why all the folks come down here from Connecticut!

What is the role of the Gulfstream/Florida Current on rainfall in PB County? I have no doubt that the strange out of the ordinary dumps (22 inches in one day), result from a related tropical phenomenon resulting from its nearby presence. At the same time, I would argue that its strength and location enhances the sea breeze that keeps the thunderstorms largely at bay in comparison to the mainland. An enigma wrapped in a riddle…

 

 

 

 

 

 

[bubba]

https://southeastfloridaclimatecompact.org/wp-content/uploads/2021/06/2020-Climate-Indicators-2.pdf

[RFun]

46 minutes ago, bubba said:

Local observation: PB Country has two seasons. May-early November= Warm/ wet; November-May=Cooler/drier. Koeppen designates this in a sweeping variation of. Tropical Savanna/Tropical Monsoon.

Warm/ wet/ November-May is characterized by high humidity and threatening thunderstorms. You must also add in Hurricane Season, which can dramatically skew results. The standard guess for annual rainfall in SE Florida is 53 inches a year, 75% of which comes during the wet season (39.75 inches v 13.25 inches/ dry season).

The numbers  are “ ballpark” and subject to dramatic alterations. Specifically, I can remember a golf superintendent buddy of mine, who faithfully kept a rain gauge on a golf course located substantially west of the Florida turnpike and I-95. His buddy was also a golf superintendent, located at the Palm Beach Par 3, located directly on the ocean. They both kept rain gauges faithfully for at least that one year. The results were quite interesting. At the golf course located west of the Turnpike, that super recorded over 110 inches for that year. Parenthetically, during the same 12 month period, the golf superintendent located on the ocean recorded 33 inches. That year was particularly dry for the barrier island of PB, because in March of that year there was a super-coastal rainfall event, which dumped 22 inches of rain in what can only be described as a strange tropical event. It was strong enough to have some effect on the western location but in large order its effect on the western location was minimal (5-7 inches). The Breaker’s Ocean golf course was literally underwater for many days. However, the seabreeze that year was particularly strong and deflected all thunderstorm activity from reaching the ocean. Correspondingly, PB could only be properly categorized as dry.

By comparison, this year’s wet season has been very wet. Worst of all, the thunderstorm activity that is usually kept west of I-95, has frequently hit the coast. I believe someone described this as a “Super El Niño” and while I am not apt to flow with stereotypical representations, this would adequately describe this year.

The dry season is approximately the remaining 6 months and spreads roughly 13.25 inches over the timeframe, resulting in approximately 2.2 inches a month. Of this average amount, it may easily fall in one day during a frontal stall, making the rest of the month to seem  desert like. This is when we experience our respite from intense heat and humidity and why all the folks come down here from Connecticut!

What is the role of the Gulfstream/Florida Current on rainfall in PB County? I have no doubt that the strange out of the ordinary dumps (22 inches in one day), result from a related tropical phenomenon resulting from its nearby presence. At the same time, I would argue that its strength and location enhances the sea breeze that keeps the thunderstorms largely at bay in comparison to the mainland. An enigma wrapped in a riddle…

 

 

 

 

 

 

Factoring in everything, not a bad amount of rainfall compared to the rest of the country, regardless.  There will be local variation.  But, we should use a general rule of thumb for this Southeastern Florida area.  This area is very far from being a desert oasis.  Those average annual yearly amounts are impressive.

[Looking Glass]

Yeah, about half of the US actually gets kind of a similar rainfall amount.  But not everywhere has daytime highs in the mid 90s and nighttime lows in the mid 80s for months on end.   Kind of looks better on paper, but when you examine how that rain falls many years, you start to understand why native grasslands in the Everglades are mostly dry and brown and how cactuses and agave do well here.  A few isolated tropical storms can account for the majority of rainfall for the entire year.  

[bubba]

I am reviving this thread after a long dormant period. This is pure conjecture and I do not claim to have any special knowledge or acumen.

We have experienced an extremely cold event in Palm Beach from February 1, 2026 through February 4, 2026. My hobbyhorse is the beneficent effect of the Gulfstream/ Florida Current on cold events, which comes closest to us because we are almost the furthest Eastern point in Florida (Palm Beach Shores). This shot of intensely cold air targeted the east coast of Florida, sparing large areas of the Gulf Coast. 

During the entirety of this event, which was an Arctic/advective incursion, the ocean temperature never dropped below 75/76F ( lots of steam). As a comparison, water temperatures in the Keys were in the upper 60s F and Miami Beach between 70 to 74° F.

My conjecture is that the constant 85° Gulfstream/Florida current, which is an ocean river that pours at a magnitude of 30m/s has a profound effect on its immediate surroundings together with the mixing elements of the atmosphere. As a comparison, all of the rivers that empty into the Atlantic and Gulf, including the Mississippi and Amazon rivers amount to .6 m/s.As a simple reflection, the massive amounts of steam radiating off the ocean water in this event demonstrates possible atmospheric involvement. My belief is that this creates a small microclimate.

Evidence of this can be seen in a comparison of the temperatures recorded at the Palm Beach, International Airport, and those temperatures recorded on a weather underground station KFLPalmMB 251 located at the Palm Beach par three golf course on the eastern side of the clubhouse. It is very close to the Atlantic Ocean. 

PBIA.                                KFLPalmMB 251

2/1 50F 31F.                      55.4F.  38.3F

2/2 59F 31F                       61.5F  39.3F

2/3 68F 40F.                      70.3F 46.7F

2/4 73F 54F                       73.0F 59.3F

I believe that this event is most similar to the 1989 freeze. PBIA recorded 41F 28F as high/lows on December 24, 1989. We experienced a quick bounce back after that cold spell and limited loss of palms and vegetation. Unfortunately, there were no weather underground stations in close proximity to the ocean.

The 2010 December cold event was different from this recent event. Specifically, it was prolonged in nature, but never yielded a below freezing temperature even at PBIA.

I will attempt to take pictures of the vegetation. At the present time, I see multitudes of coconut palms that appear to have no damage whatsoever. As we all know, however, that can change!

 

 

 

[Aceraceae]

West Palm Beach airport (KPBI) seems to have briefly dropped to 30 F actually, on the second night of the cold snap. 

[bubba]

https://www.wunderground.com/history/daily/us/fl/west-palm-beach/KPBI/date/2026-2-2

[SubTropicRay]

On 2/5/2026 at 4:02 PM, bubba said:

I am reviving this thread after a long dormant period. This is pure conjecture and I do not claim to have any special knowledge or acumen.

We have experienced an extremely cold event in Palm Beach from February 1, 2026 through February 4, 2026. My hobbyhorse is the beneficent effect of the Gulfstream/ Florida Current on cold events, which comes closest to us because we are almost the furthest Eastern point in Florida (Palm Beach Shores). This shot of intensely cold air targeted the east coast of Florida, sparing large areas of the Gulf Coast. 

During the entirety of this event, which was an Arctic/advective incursion, the ocean temperature never dropped below 75/76F ( lots of steam). As a comparison, water temperatures in the Keys were in the upper 60s F and Miami Beach between 70 to 74° F.

My conjecture is that the constant 85° Gulfstream/Florida current, which is an ocean river that pours at a magnitude of 30m/s has a profound effect on its immediate surroundings together with the mixing elements of the atmosphere. As a comparison, all of the rivers that empty into the Atlantic and Gulf, including the Mississippi and Amazon rivers amount to .6 m/s.As a simple reflection, the massive amounts of steam radiating off the ocean water in this event demonstrates possible atmospheric involvement. My belief is that this creates a small microclimate.

Evidence of this can be seen in a comparison of the temperatures recorded at the Palm Beach, International Airport, and those temperatures recorded on a weather underground station KFLPalmMB 251 located at the Palm Beach par three golf course on the eastern side of the clubhouse. It is very close to the Atlantic Ocean. 

PBIA.                                KFLPalmMB 251

2/1 50F 31F.                      55.4F.  38.3F

2/2 59F 31F                       61.5F  39.3F

2/3 68F 40F.                      70.3F 46.7F

2/4 73F 54F                       73.0F 59.3F

I believe that this event is most similar to the 1989 freeze. PBIA recorded 41F 28F as high/lows on December 24, 1989. We experienced a quick bounce back after that cold spell and limited loss of palms and vegetation. Unfortunately, there were no weather underground stations in close proximity to the ocean.

The 2010 December cold event was different from this recent event. Specifically, it was prolonged in nature, but never yielded a below freezing temperature even at PBIA.

I will attempt to take pictures of the vegetation. At the present time, I see multitudes of coconut palms that appear to have no damage whatsoever. As we all know, however, that can change!

 

 

 

Agree that this event closely resembled December 1989.  It resembled 1989 in that the focus of the cold was eastern Florida.  In 2010, the focus was Florida's west coast.  The overall severity was more 2010 than 1989.  Had this been 1989 severity,  you would have fallen below freezing on a boat offshore    Your example points out how limited the Gulf stream's effects can be in more severe events.  Even though it's not right on the beach, I wouldn't call PBI (2 miles from the beach) an inland location.   PBI would typically be spared the coldest temps as much for its coastal location as its southern latitude.  Not so this time.  In these types of events, the strip of landscaping spared by the Gulfstream can be breached by standing at the beach and throwing a rock back towards land.  If you weren't seaside or blocks from the Atlantic, you likely experienced temperatures closer to the PBI reality.  

[bubba]

Ray,

Once again, I am not a scientist/meteorologist or any expert with specific acumen. I am providing my observation that I have witnessed numerous times over the years. Specifically, when I cross the bridge over the Intracoastal, my car thermometer rises approximately 4°F when I hit the island during cold events.

I do agree that this cold event was similar to the December 1989 freeze but far less severe. At PBIA, the temperature was recorded at 42/28F. In this cold event, PBIA recorded 50/31F. I remember the difference!

I will attach to this thread, several pictures that I took today, which will demonstrate what temperature must have been experienced on the island. please keep in mind that the ocean temperature today was approximately 76°F, and there were many swimmers and surfers in the ocean. You be the judge as to whether or not these plantings suggest that the island suffered a freeze.

 

[bubba]

[bubba]

[bubba]

[bubba]

[RedRabbit]

I think the Gulf Stream is often misattributed to what’s making coastal areas warmer in South Florida. It is really a combination of latitude, urbanization leading up the coast, and the intercoastal that makes the difference. 

This latest cold event seems to support that view. If the Gulf Stream helped it should have made more of a difference. When there’s a landbreeze all the warm air from the Gulf Stream is simply pushed out to sea.