I found a new USDA hardiness map for Florida

[Jimbean]

 

I always enjoy looking at these

[Jimbean]

Compare this to the map I made a decade ago.

[PalmatierMeg]

More subdivided so maybe a bit more helpful to some people. I'm still classified as 10a but verging on 10b. And perhaps because of urban heat effect from all the building that has gone on in the past few years, including the 3-story retirement complex across the street and additional houses being built in the area, plus my location on a freshwater canal, my little microclimate might have tipped over to 10b anyway.

When I moved here in 1993, my nearest neighbor was 1/4 mile down the road and we were surrounded by barren plains of vacant lots wide open to north winds in winter.

[RedRabbit]

Thanks for sharing, but that's the prior version of the USDA map. You can tell from the URL it was uploaded in May 2012. 

http://goodlookinlawn.com/wp-content/uploads/2012/05/color-zone-map-large.gif

Interestingly, the current version was published in January 2012 so that one was already old when they uploaded it. The current version isn't perfect, but I do think it is more accurate than that one. 

 

Edited December 23, 2017 by RedRabbit

[Yunder Wækraus]

The barrier islands on the east are at least 10a all the way to Satellite Beach (roughly Melbourne); Pahokee is also at least 10a and is probably 10b. This map doesn't seem too nuanced.

[TexasColdHardyPalms]

The north side of this map doesn't jive at all with the USDA interactive map. This map has Gainesville, Ocala and Leesburg at an 8B??

[Tracy S]

Always interesting to look at the zone maps and how they are changing. Thanks for posting. 

[Xenon]

Entire northern Gulf Coast on the low end of 8b seems too conservative imo 
Jacksonville also deserves better than 8b/9a cusp
St. Pete should be zone 10? 

[kinzyjr]

It would be very difficult to create an perfectly accurate zone map of Florida.  Just in my city alone, we have areas that are borderline 8b and areas that are a very warm 9b, bordering on 10a.  Orlando has a similar situation, as do most metro areas.  The areas an hour to 2 hours north of Tampa (Spring Hill, Crystal River, etc.) are some of the coldest spots in the center of the state.  Near the coast, the climate is dramatically different than only a few miles inland with highs that are ~5-10 degrees lower and lows that are ~5-10 degrees higher.

It seems that accounting for all of the microclimatic variations would be to make a general map and then include insets for the coastal areas and the metro areas due to the heat island effects and the moderation from the Atlantic and Gulf.  Even then, you'd pretty much have to collect and analyze a reasonably large set of data from weather stations as little as a fraction of a mile apart in some areas in order to assign an accurate zone rating.

I think the maps above are more accurate than the USDA zones for the state.  Regardless of zone assignments, if we get one of those once-in-a-century cold blasts, it's always good to plan your landscape to include stuff that will survive your worst so you don't end up spending an entire year removing and replacing dead plants.

[Jimbean]

On 12/22/2017, 9:40:32, Jimbean said:

Compare this to the map I made a decade ago.

I think I should update this to make it better

[PalmTreeDude]

7 minutes ago, Jimbean said:

I think I should update this to make it better

Go for it! That would be interesting. 

[bubba]

So sick of this USDA garbage system and it’s continued promulgation. Provides an extremely narrow explanation of climate. Unfortunate example of bureaucratic lock jaw/logjam. 

[bubba]

Jim,

Your maps are outstanding works. Despite my negative commentary about the USDA criteria, I did not mean to comment negatively about your work. Perhaps you would consider an attempt using the Koppen criteria or its successors. Best, bubba 

[palmsOrl]

Problem is, that new map shows Orlando as 9a when it should at the very least be 9b, maybe even 10a (the map from a decade ago shows Orlando as zone 10a).

Also, for zone 9 on the map itself, my eyes cannot discern more than three separate colors.

Does actual data really support the coldest portion of zone 8a making it into inland NW FL?  Considering all time record lows are in the 0F- -5F range (likely colder in a few spots) though the data isn't official, maybe so.  I read somewhere once that unofficial lows as low as -8F had been recorded somewhere in the Panhandle, but of course I cannot remember where I read it.

[palmsOrl]

Kinzyjr, I noticed that about Lakeland.  I was there one summer, I believe 2008 after a very mild winter in Orlando, where the official lowest temperature was 33F-34F.  This was during an unprecedented stretch of time for Orlando between January 25, 2003 and January 9, 2010 without an official freeze.  I still have a large visible scar on my shin from slipping on ice on my parents dock in Maitland on January 24, 2003.

In Lakeland on that occasion, I saw completed fried Phoenix robellebii, Bismarckia, and of course zone 10 stuff.  It had clearly dipped into the mid 20s in many areas of Lakeland the previous winter.

[RedRabbit]

Did you guys miss my post about this being an old map? There's no harm in discussing it, but I'm kind of surprised given it's just the predecessor to the current USDA map. 

[kinzyjr]

47 minutes ago, palmsOrl said:

Problem is, that new map shows Orlando as 9a when it should at the very least be 9b, maybe even 10a (the map from a decade ago shows Orlando as zone 10a).

Also, for zone 9 on the map itself, my eyes cannot discern more than three separate colors.

Does actual data really support the coldest portion of zone 8a making it into inland NW FL?  Considering all time record lows are in the 0F- -5F range (likely colder in a few spots) though the data isn't official, maybe so.  I read somewhere once that unofficial lows as low as -8F had been recorded somewhere in the Panhandle, but of course I cannot remember where I read it.

Crestview, known as Florida's Icebox, can get pretty chilly in the winter.  I think they have mountain laurel growing in spots up that way.

35 minutes ago, palmsOrl said:

Kinzyjr, I noticed that about Lakeland.  I was there one summer, I believe 2008 after a very mild winter in Orlando, where the official lowest temperature was 33F-34F.  This was during an unprecedented stretch of time for Orlando between January 25, 2003 and January 9, 2010 without an official freeze.  I still have a large visible scar on my shin from slipping on ice on my parents dock in Maitland on January 24, 2003.

In Lakeland on that occasion, I saw completed fried Phoenix robellebii, Bismarckia, and of course zone 10 stuff.  It had clearly dipped into the mid 20s in many areas of Lakeland the previous winter.

Yes, it's definitely hit or miss.  @JayW posted a picture of his thermometer during the Jan. 2010 freeze showing a reading of 16.7F.  I lived near I-4 at the time, right in the middle of the most urban part of Lakeland, and we bottomed off at 26F.  In less than 10 miles there was a 10 degree difference.

Here is the post from Jay during that event where it hit 16.7:

http://www.palmtalk.org/forum/index.php?/topic/21494-persistent-cold-air-in-florida/&do=findComment&comment=361961

Here is a post from Houzz (formerly GardenWeb) where Jay posted as jayinflorida and shared a few images including a radar graphic showing the snow line.  Jay got snow, my location didn't:

https://www.houzz.com/discussions/2087751/central-florida-heat-island-effect-warning-graphic-photos

23 minutes ago, RedRabbit said:

Did you guys miss my post about this being an old map? There's no harm in discussing it, but I'm kind of surprised given it's just the predecessor to the current USDA map. 

In my case, just discussing zone maps in general.  Didn't overlook you there, buddy.

 

 

[RedRabbit]

52 minutes ago, kinzyjr said:

In my case, just discussing zone maps in general.  Didn't overlook you there, buddy.

It is certainly an interesting topic. Each map seems pretty flawed from what I've seen.  This one does a reasonably good job on the west coast, but the east coast is off.

So far I think screenshots from Wunderground taken on cold nights do the best job of reflecting the climate. 

[Jimbean]

On 12/2/2018, 4:35:50, bubba said:

Jim,

Your maps are outstanding works. Despite my negative commentary about the USDA criteria, I did not mean to comment negatively about your work. Perhaps you would consider an attempt using the Koppen criteria or its successors. Best, bubba 

I will most certainly consider it.  I'll toy around with a number of ideas.

[bubba]

That would be great!

[pj_orlando_z9b]

For the map showing all the microclimates, I agree to an extent on radiational nights but when advective cold hits, the lakes provide minimal help. Last winter was a good example. In the Jan event, it was widespread 27-28F across the entire Orlando metro area. But on radiational nights like last week, I bottomed out at 46F when it was 38F 5 miles to my east. I'm on the SE side of an 1800 acre lake.

Edited December 4, 2018 by pj_orlando_z9b

[Jimbean]

On 12/2/2018, 7:35:50, bubba said:

Jim,

Your maps are outstanding works. Despite my negative commentary about the USDA criteria, I did not mean to comment negatively about your work. Perhaps you would consider an attempt using the Koppen criteria or its successors. Best, bubba 

This is a very rough shot at it.  Inside the red zone is the tropics (Caribbean ecosystem), above the purple line is southeastern forest ecosystem, between the orange and the purple lines is the Florida ecosystem I think we are familiar with and the orange zone the transition between central Florida and Caribbean ecosystems. 

[bubba]

This is sensational and you should apply for a copyright!

[Jimbean]

1 hour ago, bubba said:

This is sensational and you should apply for a copyright!

I forgot to give credit to the source of the original map.

It was from the Bureau of Watershed Management, Division of Environmental Assessment and Restoration, published in 2007

Edited December 6, 2018 by Jimbean

[bubba]

Was the “Atomic Coastal Strip” nomenclature developed during the Cuban Missle Crisis?

[Jimbean]

19 minutes ago, bubba said:

Was the “Atomic Coastal Strip” nomenclature developed during the Cuban Missle Crisis?

That's what I'm guessing.  I googled it and did not find a clear answer.

[bubba]

Truly sounds Dr. Strangeloveesque!

[Jimbean]

I might make another make which is more thoughtful, although I think it's pretty straight foward.  Basically there are the southern hardwood forest/pine forests of the south in north Florida, Caribbean tropical in the extreme south, and the Florida subtropical, dominated by saw palmetto/slash pine in between.