Some interesting Hardiness zone research

[Southwesternsol]

I was doing some web browsing and found an interesting page showing how much hardiness zones have shifted. I'm not sure if this has been posted here before, but I thought it was quite interesting. Closest city to me is Albuquerque, and it lines up with what I've noticed anecdotally. 

 

Overview of the research. https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023

See the graphs showing the changes https://www.climatecentral.org/graphic/shifting-planting-zones-2023?graphicSet=Local+Shifting+Planting+Zones&location=Anniston&lang=en

[SeanK]

Great News given that we're still on the cold side of the 5,000,000-year average.

[RFun]

I'd go to weather.gov and look under the "Past Weather" section.  I've found that if you look up 100 years of data, you'll get a better gauge of your area's hardiness.  Otherwise, if you use shorter periods of time (i.e., USDA Hardiness Zone Map), you're going to find it fluctuates back and forth in many areas of the country.  Also, consider things like length of below freezing cold snaps, wind, sheltered spots, backyard microclimates, etc.

[Zeeth]

Interesting website. I'm kind of interested what the individual data points on the graph means, as it seems to mean something other than low temp for that year (maybe it's average predicted low for each year?). I did some playing with numbers for the Tampa Airport and I do get a similar trend over the time period they measured. 

 

According to this, Tampa's average low was slightly under 29, and now it's right at 33

 

Using historical data with a simple linear trend, I get just below 28 for 1951 and just above 33 for 2022. Pretty similar.

 

TPA has more data to look through though, so I brought the data out to 1938, and the trend is similar but less noticeable. Starts just below 30 and ends just above 32. 

 

I noticed there's also a data set called "Tampa Area" that uses TPA data for recent data sets but goes back to 1890 (not sure where it's drawing old data from. The trend looks less significant on this one, but from about 30 to about 32:

 

I did notice in all these data sets that the 60s and 80s were abnormally cold and seem to skew things down. I did a chart where got rid of everything between 1960 and 1989 to see what that did. Not sure how useful this is considering this area could see those temps again, but here's that data.

[Foxpalms]

The same thing is happening here. 

[RFun]

So basically, what we don't know is if the warming trends will continue or if they will they revert back to a more average condition.  Those 2000-2022 average minimum temps are quite warm for many areas of the country.

Edited October 23, 2023 by RFun

[Silas_Sancona]

On 10/21/2023 at 5:13 PM, Southwesternsol said:

I was doing some web browsing and found an interesting page showing how much hardiness zones have shifted. I'm not sure if this has been posted here before, but I thought it was quite interesting. Closest city to me is Albuquerque, and it lines up with what I've noticed anecdotally. 

 

Overview of the research. https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023

See the graphs showing the changes https://www.climatecentral.org/graphic/shifting-planting-zones-2023?graphicSet=Local+Shifting+Planting+Zones&location=Anniston&lang=en

Had seen this a few months ago.. As others have mentioned, lines up with what has been observed here, in Tucson, ..and in various parts of CA., esp. where i grew up out there.  Only someone with their head firmly thrust deep in the sand wouldn't notice how things have ..and continue to change.

My only gripe is the site ( like others )  doesn't include enough cities.. IE:  Less densely populated places around AZ like Superior, Quartzite, Kingman, Show Low, Winslow, and Payson, Prescott,  Buckeye, Queen Creek, Nogales,  Sonoita, Sierra Vista and Wilcox here,  ...and places like Hollister, Santa Cruz, Santa Barbara, Oxnard / Ventura,  Ramona, Hemet / San Jacinto,  Livermore, Santa Rosa, Eureka, Julian, Hesperia / Victorville, etc in California..  Yea, you can use data from the bigger cities to get an idea of what is likely occurring in the smaller / less densely developed areas, but, i would like to see hard data from each individual place.  Regardless,

One can get a good idea that things are warming by being aware of what " warmer climate " critters are exploring  ..then establishing new populations in previous territory X critter considered too chilly, and what cooler adapted things are struggling, and / or dying off out as it gets too warm for them to survive in X now warmer area. 

[flplantguy]

Current sea and land temps are setting crazy records so who knows what the next cycle will bring. There are a couple threads here regarding this subject, and my theory is a few subtle changes have led to less major events, and so when they do happen they don't schew that average much at all.  This past Christmas freeze set records in many places, but was a non event past Tampa really in terms of records and cold duration, likely due to more energy present in the lower latitudes that blocks the extreme cold from penetrating south-or being as cold when it does.  Combine this with less snow cover and ice, a weird jet stream, and the resulting polar vortex anamolies, and you get less severe cold outbreaks overall and a warming average as the disparity between the two is lessened.  Just this past week a cold front came through here and lowered temps to the mid forties, which was the same as most of the eastern US almost to Canada.  That shouldn't happen, there should be a difference that far apart that just wasn't there.  Once the hemisphere cools that changes, but a shorter period for cold to build is yet another reason the coldest nights are warmer.  I would never use one factor in planting, and I think we have to carefully consider plantings for this since we don't know if that wacky pendulum will swing cold for one night in the period that ruins all your hard work. Use the records in your decisions for both heat and cold and hope for the best.

[Jimbean]

There's no graph for Melbourne, but here is Orlando and West Palm Beach

[Jimbean]

Here's the shifting zone map according to that site

[Aceraceae]

8 hours ago, Zeeth said:

I'm kind of interested what the individual data points on the graph means, as it seems to mean something other than low temp for that year (maybe it's average predicted low for each year?). I did some playing with numbers for the Tampa Airport and I do get a similar trend over the time period they measured. 

It looks like it might be every two years is one dot and it's smoothed. 

[Southwesternsol]

9 hours ago, RFun said:

I'd go to weather.gov and look under the "Past Weather" section.  I've found that if you look up 100 years of data, you'll get a better gauge of your area's hardiness.  Otherwise, if you use shorter periods of time (i.e., USDA Hardiness Zone Map), you're going to find it fluctuates back and forth in many areas of the country.  Also, consider things like length of below freezing cold snaps, wind, sheltered spots, backyard microclimates, etc.

Yeah, I just stumbled across it and thought it was a nice visualization. 

[RFun]

18 minutes ago, Southwesternsol said:

Yeah, I just stumbled across it and thought it was a nice visualization. 

It could be an indication of what is to come with those future temperatures.  That's what we don't know yet.

[RedRabbit]

22 hours ago, Zeeth said:

Interesting website. I'm kind of interested what the individual data points on the graph means, as it seems to mean something other than low temp for that year (maybe it's average predicted low for each year?). I did some playing with numbers for the Tampa Airport and I do get a similar trend over the time period they measured. 

 

According to this, Tampa's average low was slightly under 29, and now it's right at 33

 

Using historical data with a simple linear trend, I get just below 28 for 1951 and just above 33 for 2022. Pretty similar.

 

TPA has more data to look through though, so I brought the data out to 1938, and the trend is similar but less noticeable. Starts just below 30 and ends just above 32. 

 

I noticed there's also a data set called "Tampa Area" that uses TPA data for recent data sets but goes back to 1890 (not sure where it's drawing old data from. The trend looks less significant on this one, but from about 30 to about 32:

 

I did notice in all these data sets that the 60s and 80s were abnormally cold and seem to skew things down. I did a chart where got rid of everything between 1960 and 1989 to see what that did. Not sure how useful this is considering this area could see those temps again, but here's that data.

I feel like I can almost see in the graph where they moved the weather station. TPA always reads too high now. 😕

[kinzyjr]

@Zeeth @RedRabbit

I can confirm that the 33F mark is indeed the Average Annual Low over the last 30 years at KTPA in the NOAA data.  It's been well publicized that this station tends to read high, but there is some solace in the fact that over 84 years of data the average still comes up over 30F (10a).  That solace is reduced by the all-time low of 18F in Dec. 1962.

[RFun]

38 minutes ago, kinzyjr said:

@Zeeth @RedRabbit

I can confirm that the 33F mark is indeed the Average Annual Low over the last 30 years at KTPA in the NOAA data.  It's been well publicized that this station tends to read high, but there is some solace in the fact that over 84 years of data the average still comes up over 30F (10a).  That solace is reduced by the all-time low of 18F in Dec. 1962.

I'll take your word for it.  Sounds about right to me.

[kinzyjr]

41 minutes ago, RFun said:

I'll take your word for it.  Sounds about right to me.

Not my word, NOAA's 🙂

The map shown is just NOAA data condensed to a Google Map:

https://www.google.com/maps/d/viewer?mid=1QCS-fTHGPmghnQJ7Q1phu7gSXSD6Rtxq&ll=28.184540444216204%2C-80.22796641685483&z=9

[RFun]

21 minutes ago, kinzyjr said:

Not my word, NOAA's 🙂

The map shown is just NOAA data condensed to a Google Map:

https://www.google.com/maps/d/viewer?mid=1QCS-fTHGPmghnQJ7Q1phu7gSXSD6Rtxq&ll=28.184540444216204%2C-80.22796641685483&z=9

Lol...I tried to tell them it was impossible to map.  I see they still made the attempt. 

[flplantguy]

I wonder what the average is if you take out the odd extremes and use only the "typical" years. For every coldest year the warmest is also removed, all the way back to the first year, ideally pre 1900. Maybe with the extremes removed it paints a different picture of the average on a typical year outside that few hours below say 25 for Tampa. I may have to do the math and see if I have time.

[kinzyjr]

29 minutes ago, flplantguy said:

I wonder what the average is if you take out the odd extremes and use only the "typical" years. For every coldest year the warmest is also removed, all the way back to the first year, ideally pre 1900. Maybe with the extremes removed it paints a different picture of the average on a typical year outside that few hours below say 25 for Tampa. I may have to do the math and see if I have time.

The numbers you'll need are condensed in spreadsheet form here:

https://www.palmtalk.org/forum/topic/66320-florida-freeze-and-weather-station-data/?do=findComment&comment=1064607

Look for spreadsheet 2022_FloridaWeatherAlmanac.xlsx

It will at least save you a little bit of time by giving you the annual low for each year the station of your choice recorded data.

[Xerarch]

2 hours ago, kinzyjr said:

Not my word, NOAA's 🙂

The map shown is just NOAA data condensed to a Google Map:

https://www.google.com/maps/d/viewer?mid=1QCS-fTHGPmghnQJ7Q1phu7gSXSD6Rtxq&ll=28.184540444216204%2C-80.22796641685483&z=9

That's actually pretty cool

[RFun]

50 minutes ago, Xerarch said:

That's actually pretty cool

Not a bad attempt by any means.  Of course, the fine details are always lacking with these.  I'd prefer a 100 year average minimum temperature as a better guide of things.  But, 70 years wouldn't be a bad gauge either.

Edited October 25, 2023 by RFun

[flplantguy]

If we could add all the data from personal weather stations to that map and remove the odd outliers it would fill in gaps, but would still be imperfect for microclimate.  My area needs more stations that's for sure.  Records from a century ago are spotty and from a time when there were no cities and less human activity to create heat islands and baren cold holes where all the trees were removed.  Florida, especially south of I4 (almost an urban heat island "wall" against cold now), has changed a lot since before people made it what it is now.  Once it is all built up (and the natural spaces are destroyed🙄) it will be even more noticable here and other places where cities and water dominate. San Diego is another good example of an area that doesn't see regular freezes now since the city took over and it's now a zone higher than before. I imagine many cities will continue this trend with rural stations slowly reflecting the background warming.  All this means nothing when a natural disaster destroys your yard though; it doesn't have to be a cold event either.

[kinzyjr]

1 hour ago, RFun said:

Not a bad attempt by any means.  Of course, the fine details are always lacking with these.  I'd prefer a 100 year average minimum temperature as a better guide of things.  But, 70 years wouldn't be a bad gauge either.

The 100-year and All-Time (all records for the station) statistics are included on the map and the sheet, although the map uses 50-years for the coloration.  Making a map with the spreadsheet in my response to @flplantguy for 100 years isn't terribly difficult.  Basically, it just involves setting the coloration for the AAL 100 ZONE column instead.  I did a quick check to see how different they were and only 78 of the stations were different out of 368.  I'm sure this is helped by the fact that a bunch of them have less than 100 years of data. 

50 years is actually a really good benchmark as it includes the 1977 freeze where snow was recorded in the northern Bahamas as well as the 1980s; with three 100-150 year freezes in one decade.  Many stations recorded or tied their record lows during those events.

1 hour ago, flplantguy said:

If we could add all the data from personal weather stations to that map and remove the odd outliers it would fill in gaps, but would still be imperfect for microclimate.  My area needs more stations that's for sure.  Records from a century ago are spotty and from a time when there were no cities and less human activity to create heat islands and baren cold holes where all the trees were removed.  Florida, especially south of I4 (almost an urban heat island "wall" against cold now), has changed a lot since before people made it what it is now.  Once it is all built up (and the natural spaces are destroyed🙄) it will be even more noticable here and other places where cities and water dominate. San Diego is another good example of an area that doesn't see regular freezes now since the city took over and it's now a zone higher than before. I imagine many cities will continue this trend with rural stations slowly reflecting the background warming.  All this means nothing when a natural disaster destroys your yard though; it doesn't have to be a cold event either.

The map does include some Weather Underground data for the Lakeland area that I scraped to gauge how much milder downtown was during the winter and where the heat island effect dissipated enough to start concerning growers.  Unfortunately, doing this for one locality without any kind of automation or AI was tough enough as you can't rely on the stations being appropriately sited, even if the property owner has a lot of open space.  In my own case, I don't have a single spot in my yard to record an "official temperature" and what I do record varies as much as 4F depending on where I record it.  The record keeper ends up looking for high-end stations like DVP2 and then visiting their location to verify that the reading is worthy of being included.

As you mentioned, radiational cold events often show stark differences around urban areas, and the January 2022 Florida Freeze Report illustrates this pretty well using Wodyetia bifurcata as the proverbial canary in the coal mine.  Having this data helped to provide the folks who attended the Fall 2022 CFPACS Meeting here a data-driven map of how what they saw inside the heat island and in the Highlands compared to what happens less than 10 miles away.

You mentioned spotty old records, and that is an issue.  Another issue is that the low temperature records used to be taken at 7AM, which is not always as low as it goes.  A useful alternative for our hobby are @Jimbean + @RedRabbit's method of mapping where Roystonea regia and Cocos nucifera that are pre-2010 and pre-1989 exist.

3 hours ago, Xerarch said:

That's actually pretty cool

Thank you.  I've come across some additional data points that I could add to the 2023 edition if I get a chance to publish one, but time has been scarce as hens' teeth lately.  The Zephyrhills Airport (KZPH) was the first site of this nature that I included on a map, and it was informative as to where the climate actually starts changing.  Hopefully the bulk of the other data will be scraped and give me enough time to kick off the SQL jobs that perform the calculations for the spreadsheet.

[Xenon]

2 hours ago, flplantguy said:

If we could add all the data from personal weather stations to that map and remove the odd outliers it would fill in gaps, but would still be imperfect for microclimate.  My area needs more stations that's for sure.  Records from a century ago are spotty and from a time when there were no cities and less human activity to create heat islands and baren cold holes where all the trees were removed.  Florida, especially south of I4 (almost an urban heat island "wall" against cold now), has changed a lot since before people made it what it is now.  Once it is all built up (and the natural spaces are destroyed🙄) it will be even more noticable here and other places where cities and water dominate. San Diego is another good example of an area that doesn't see regular freezes now since the city took over and it's now a zone higher than before. I imagine many cities will continue this trend with rural stations slowly reflecting the background warming.  All this means nothing when a natural disaster destroys your yard though; it doesn't have to be a cold event either.

When the apocalyptic 30+ mph NW wind several day freeze polar express comes, the UHI will be mostly negated and even water moderation is greatly diminished. When it comes, the only saving grace is latitude/delaying the arrival of the front as long as possible. Houston's (population 7.2+ million) heat island insulated against extreme zone busting cold for 30 years and then it all came crashing down in 2021 😅. Dallas (population 7.6+ million) came one degree shy of tying its all time record low despite all of the development. 

 

 

[mnorell]

7 hours ago, flplantguy said:

I wonder what the average is if you take out the odd extremes and use only the "typical" years. For every coldest year the warmest is also removed, all the way back to the first year, ideally pre 1900. Maybe with the extremes removed it paints a different picture of the average on a typical year outside that few hours below say 25 for Tampa. I may have to do the math and see if I have time.

"Typical" temperature is, in statistics, called the "modal" temperature or just the "mode." This is the most commonly occurring temperature in a given circumstance/time-period. Basically, you need to get all the data-points for a given date (or range of dates), graph them in a distribution (such as a bar-chart), then find the most common temperature (highest bar) for that date, or period of days. This is a very valuable data-point, though the other statistic you will want to know (to use along with the mean/average) is your standard deviation. These two numbers will give you a very firm idea of the temperature you are likely to experience on any given day; and also how variable you can expect any day (or month, year, etc.) to be as compared to the average/mean temp. A city like Key West, for example, has a very low standard deviation in winter, since temperatures are moderated by a very large, and generally very warm, bathtub of water that does a lot to modify intruding bodies of anomalous air temperature. On the other hand, an inland location like Kansas City will have a quite high standard deviation in winter since it is subject to highly changeable weather, affected both from the north and the south, in a land-mass-dominated area that has little hope of changing the temperature of mass importations of warm or cold air.

Meteorologists are well aware of these statistical numbers and use them in guiding their forecasts. Unfortunately we mere mortals are generally locked out of such data without shelling out significant $$$ for it. I personally don't know where you can get this information without subscribing to a dedicated data service. It is possible, however, to manually download data from sources such as NOAA's NOWData system, and graph them yourself to get an answer. Tedious but very useful for those of us trying to gamble more intelligently on what we should plant in a given place. Excel has the operands necessary to extract this info but you have to have the large data-set first. If anybody knows where one can download the mode and standard deviation for various locations, I for one would be grateful to know where that might be...

[flplantguy]

I tried the mode for st leo and it's 29.  The average of those same 128 years of data is 27.8, for a difference of just over a degree.  I think that means that the coldest years do schew the data, but only a slight amount and not enough to change the zone at all.  I chose this station for the location out of the heat island and for the long data range.  The thirty year mode used for zones is 28 for the same station so the range is actually pretty stable.

[RedRabbit]

When it comes to climate data and identifying microclimates, I think the screenshots we've taken during cold events are extremely valuable. If you could mesh them all together you'd generate an amazing zone map.  We know it's not perfect though because there are bad stations or missing stations.

I'd like to mention there's one climate model that performs well on cold events. Here's a screenshot of HRRR from January 2022:

 

The only real issue I see with it is it omits Lake Tarpon and maybe under appreciates some UHI aspects, but otherwise the contours really nailed the local zones. I'll be keeping an eye on it going forward, it may be useful for filling in some gaps where we don't have data or our data is bad.

Other models like the Euro and GFS actually don't do particularly well (they seem to think Tampa Bay helps areas to the north, which it doesn't.) 

Edited October 25, 2023 by RedRabbit

[flplantguy]

I noticed those missed the quick fast drop around dawn also.  My low in the area was on the forecast till the last three hours that night, when it did a fast dip down below freezing to upper 20s then back up again.  It damaged some plants, but not even enough to drop leaves, so duration is important too and that's not reflected either.  2018 defoliated and killed back the upper two feet of the Brazilian peppers here; that freeze and this last winter did not and the actual readings were not much different.  These variables are why I pick the lowest model (within reason) and go from there since they can miss the quick dip.  If inland areas get a freeze warning I apply that to my spot also, as I do not think they factored in that part of the county when they created the zone. Last year's frost advisory was a low of 31, so I use the inland warnings now and hope I will overdo it. I was complacent once in 2018 and got lucky nothing major died, so not again.

[RFun]

Certainly, none of these attempts at maps are going to be completely accurate by any means.  And plants couldn't care any less about one's attempts to map temperature "hardiness zones".  Having said that, I will definitely admit that the 50 or 100 year stretches are likely going to be slightly colder because a lot of those earlier years did not have the man made built-up environment as prolific in many areas as it has been in more recent years.  Just an educated guess....

Edited October 26, 2023 by RFun

[SeanK]

On 10/23/2023 at 2:11 PM, Zeeth said:

Interesting website. I'm kind of interested what the individual data points on the graph means, as it seems to mean something other than low temp for that year (maybe it's average predicted low for each year?). I did some playing with numbers for the Tampa Airport and I do get a similar trend over the time period they measured. 

 

According to this, Tampa's average low was slightly under 29, and now it's right at 33

 

Using historical data with a simple linear trend, I get just below 28 for 1951 and just above 33 for 2022. Pretty similar.

 

TPA has more data to look through though, so I brought the data out to 1938, and the trend is similar but less noticeable. Starts just below 30 and ends just above 32. 

 

I noticed there's also a data set called "Tampa Area" that uses TPA data for recent data sets but goes back to 1890 (not sure where it's drawing old data from. The trend looks less significant on this one, but from about 30 to about 32:

 

I did notice in all these data sets that the 60s and 80s were abnormally cold and seem to skew things down. I did a chart where got rid of everything between 1960 and 1989 to see what that did. Not sure how useful this is considering this area could see those temps again, but here's that data.

Seems if we go back to the Eisenhower era, temps were in a higher portion of the cycle.

[Aceraceae]

The '30s to '50s had a lot of heat events and warm years, such as the Dust Bowl, and the 60s to 80s or even the 50s to 90s had a lot of serious cold, depending on location. Look at the mid south using Current Results .com Raleigh NC lowest temperature each year pages for example where 1960 to 1989 had all the record lows compared to later and somewhat before. It'd be interesting to compare a full Wikipedia style climate chart of those two fully separate periods, 1961 to 1990 and 1991 to 2020, to see if the average temps follow the minimums. 1990 had a very warm minimum though so 1961 to 1989 and 1990 to present would be better. 

Edited October 31, 2023 by Aceraceae

[Desert DAC]

On 10/21/2023 at 6:13 PM, Southwesternsol said:

I was doing some web browsing and found an interesting page showing how much hardiness zones have shifted. I'm not sure if this has been posted here before, but I thought it was quite interesting. Closest city to me is Albuquerque, and it lines up with what I've noticed anecdotally. 

 

Overview of the research. https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023

See the graphs showing the changes https://www.climatecentral.org/graphic/shifting-planting-zones-2023?graphicSet=Local+Shifting+Planting+Zones&location=Anniston&lang=en

Yes - -parts of ABQ are indeed showing to be barely zone 8a, though probably a different area than the PRISM maps. I put the monthly and annual coldest temperatures from ABQ going back to the 1890's (rather complete records), then grouped them into both different locations, and into 10, 30 year (what USDA cold hardiness zones use now), and POR (period of record). In fact I did that for Santa Fe (but only to 1970-ish), Las Cruces NMSU, El Paso, Austin TX, and maybe another few places.

Climate Central has a mix of erroneous outlooks and some good information / nice graphics, so I prefer to go to the source - NOAA, the Western Climate Center, including the 1991-2020 normals. Grouping Santa Fe and ABQ as a climate trend as if they are related, is one glaring example of that issue. 

Albuquerque is more like Las Cruces over the year, most any season, or all-time POR, than ABQ is like Santa Fe. Growing season length, extremes or averages, durations of <32F or above 90F, native species or cultivated vegetation that's actually successful, and so on.

Yet each of those three are still in a different climate zone than the other. Bernalillo - Socorro one zone, T or C to Las Cruces or El Paso another zone, Santa Fe to Espanola Valley another, Taos another, and so on. 

Not sure where your Four Corners locale lies as to climate zones, but looking at NOAA it seems like a Farmington, Grand Jct, or at the mildest an Espanola Valley or Santa Fe.

Just needed to clarify that, whenever I see the false equivalency of some people's insistence on a "Santa Fe & Albuquerque", having lived in both, ABQ the longest, and as a former, practicing landscape architect with much practical experience and research. That Climate Central Graph with it's zone 7b to 8a shift should read "Albuquerque-Socorro"!

[Desert DAC]

On 10/31/2023 at 1:10 AM, Aceraceae said:

The '30s to '50s had a lot of heat events and warm years, such as the Dust Bowl, and the 60s to 80s or even the 50s to 90s had a lot of serious cold, depending on location. Look at the mid south using Current Results .com Raleigh NC lowest temperature each year pages for example where 1960 to 1989 had all the record lows compared to later and somewhat before. It'd be interesting to compare a full Wikipedia style climate chart of those two fully separate periods, 1961 to 1990 and 1991 to 2020, to see if the average temps follow the minimums. 1990 had a very warm minimum though so 1961 to 1989 and 1990 to present would be better. 

The comparison breakdown you describe really helped me to understand different periods here (desert southwest. I entered monthly extreme low temperatures into an Excel spreadsheet, then summarized each 10 year to 30 year to 130+ year (period-of-record) timeframe. It revealed so much.

Turns out the 1950's were the longest period of hottest / driest weather in 130 years where I am. The 1960's and 1970's were about the coldest period (where some like to start graphing for their reasons), and the mid 1990's and 2023-24 the hottest ever summers...June through October. 

[CascadiaPalms]

Portland Oregon was pushed to a 9a zone in the last update.