Central Florida winter approaching, some averages for Orlando

[palmsOrl]

With the cool season approaching and a record number of super-marginal stuff in the ground (and in pots destined to be planted out in spring), I decided to compile some official low temperature data for the Orlando area, so I feel I can:

A. Be more prepared for and anticipate the cold weather that our area can and has experienced.

B.  Identify the worst case scenario type winter and also what a typical winter should be in our area.  Has a typical winter for the Orlando area become warmer than it used to simply due to all of the development the area has experienced? 

C. Establish from the data just how much the urban heat island effect has expanded our choice of more cold sensitive palms.  How much has the worst case scenario improved over time?

I will start with an average annual minimum temperature from the Orlando Executive Airport (well inside the Orlando urban heat island) from the 27 years of reliable data available (1988-2015): The average over this period has been 32.32F

The Orlando International Airport (probably best representing the Orlando area as a whole) during the same period ('88-'15) has had an annual average low of 31.11F, while the average when all reliable data ('53-'15) is included is 29.62F.

Data from Sanford International Airport is a bit less reliable as many days report the low only from when hourly reports are noted (often from 8:00am-8:00pm), so I suspect the historical data from this station is skewed toward the high side.  The city is 25-30 miles north of Orlando and averages are significantly lower than those of Orlando during the cool season.  Bearing this in mind, the average lowest temp from (1988-2015) for the Sanford station is 30.81F

I have more to add about all this (and will do so as the thread continues) but with all of the climate/USDA zone discussion debate on here for the past several years I had been meaning to do this to see what the actual data showed about the area's recent climate.

[Ed in Houston]

On 10/19/2015, 11:06:02, palmsOrl said:

With the cool season approaching and a record number of super-marginal stuff in the ground (and in pots destined to be planted out in spring), I decided to compile some official low temperature data for the Orlando area, so I feel I can:

A. Be more prepared for and anticipate the cold weather that our area can and has experienced.

B.  Identify the worst case scenario type winter and also what a typical winter should be in our area.  Has a typical winter for the Orlando area become warmer than it used to simply due to all of the development the area has experienced? 

C. Establish from the data just how much the urban heat island effect has expanded our choice of more cold sensitive palms.  How much has the worst case scenario improved over time?

I will start with an average annual minimum temperature from the Orlando Executive Airport (well inside the Orlando urban heat island) from the 27 years of reliable data available (1988-2015): The average over this period has been 32.32F

The Orlando International Airport (probably best representing the Orlando area as a whole) during the same period ('88-'15) has had an annual average low of 31.11F, while the average when all reliable data ('53-'15) is included is 29.62F.

Data from Sanford International Airport is a bit less reliable as many days report the low only from when hourly reports are noted (often from 8:00am-8:00pm), so I suspect the historical data from this station is skewed toward the high side.  The city is 25-30 miles north of Orlando and averages are significantly lower than those of Orlando during the cool season.  Bearing this in mind, the average lowest temp from (1988-2015) for the Sanford station is 30.81F

I have more to add about all this (and will do so as the thread continues) but with all of the climate/USDA zone discussion debate on here for the past several years I had been meaning to do this to see what the actual data showed about the area's recent climate.

November data for Houston Hobby Airport.

Average high was 74.2

Average low was 57.1

November was 2.5 degrees above normal (1981-2010 used as baseline).

Ed in Houston

 

 

 

 

 

[Bill H2DB]

I added this to the Daytona -history thread , but more appropriate here?

 

December in Orlando by Bill H, on Flickr

[Eric in Orlando]

18 in 1984. That was a horrible winter, 1894-95. Severe freeze in Dec then another whopper in Feb 1985. It totally wiped out the citrus industry in north FL and pushed it all down to central FL. But even in central FL it was devastated and took years before it was replanted. The trees were severely damaged in Dec. 1984 but survived. Jan. 1985 had mostly mild weather so they started growing back but then another super freeze hit in Feb. It came quick. From what I have read Orlando went from a high of 85 to a low of 17 in the same day.

[palmsOrl]

Bill, thank you for posting the Orlando data in the same format.  The average Orlando highs for the end of December are more what I would expect in mid-January.

Eric, that would absolutely be a record temperature variation for our location if official.  I assume it was 85 in the late morning or early afternoon on day, then 17F by sunrise the next day.  That would blacken even the live oak canopies!  I believe rural areas in general around Orlando are capable of seeing even mid-teens once a century or so (or every 200 years certainly).

Edited December 7, 2015 by palmsOrl

[Eric in Orlando]

It would have been an incredible drop. Reports from back then said it sounded like shotgun blasts all night in the groves. The sap in the trees froze and expanded causing the bark to explode.

I know a couple growers who told me they recorded around 14-15F in the Dec. 1989 freeze. The were up in the Plymouth-Sorrento area. They even had around 17-18F during the 2009-10 winter. There are some cold, cold pockets in that area. Its very hilly so you can end up in a very bad cold drainage spot.

 

 

 

 

[Mr. Coconut Palm]

Wow!  You guys have had it almost as rough as here in Texas.  '83 and '89 were brutal with teens even in Brownsville, and in '89 it got down to 17F at South Padre Island (a normal 10B coconut growing climate)!  But I think back then, South Padre was barely 10A and Brownsville was at the high end of 9B.  Now, 10A extends all the way up the coast to North Padre Island, Port Aransas, Flour Bluff, and the East end of Ocean Dr. in Corpus Christi.  Galveston has been a 10A climate for many years, but a low end very cool 10A winter climate as opposed to the milder 10A climates we have here to the South.  Almost all the Rio Grande Valley now from McAllen and Edinburg to Harlingen and Brownsville are 10A, with South Padre now 10B.  Anyway, the all time record low here in Corpus Christi was 11F and in Brownsville 12F, but these are very rare once in 150 to 200+ year events.

[SubTropicRay]

Central Florida freeze season opens tomorrow (Dec 10) and runs through February 20th.  96% of all widespread central Florida freezes occurred between these dates.  More importantly, no widespread freezes outside of these dates have occurred since 1980.  By coincidence, the AO could go negative by months end meaning a potentially cool start to January.     

[palmsOrl]

It appears we have some chillier weather on tap for this coming weekend.  Yesterday evening, the NWS had us getting down to 42F on Saturday but they have now revised the temperatures up so our lowest forecast low is 47F.  This winter may end up being a breeze for all the zone pushers around here, though it is way too early to come to any conclusions.  So far, each cool/cold weather "milestone" is coming both much later than expected and is milder than expected.  Even the real tender stuff can handle a couple nights in the upper 40s, so no dragging around blankets and heaters yet.  Historically, Orlando has been as low as the low 20s in mid-December.  I used to wish for the cold weather (as some of you may remember seeing in my posts), but I am now so heavily invested in tropicals at this point that I am happy to see such mild conditions stretch into our coolest months of the year (and into our freeze season).  Here's hoping we don't go below 45F until January!

[Zeeth]

I'm happy about our warm weather so far, but I keep reminding myself that it's not winter yet. I'm too busy and too far from my garden to protect anything if the real cold does come, so I'm going to let nature take it's course. My original purpose for my large coconut collection was to see if I could find a coconut that is cold hardier than the Malayans commonly available here, so I guess it's time to see how long they last unprotected in my somewhat marginal location 2 miles from the Gulf. 

[Ed in Houston]

After 14 days into December, Houston is 4 degrees above normal for the month. Coldest forecast till xmas is 42F. Hoping for a mild winter so the newly planted  Pinanga coronata var. 'kuhlii' has a chance to make it through the winter. It is planted in the warmest part of the garden against the S.E wall of the house under the canopy of a 25 foot grapefruit tree. That spot runs about 3 degrees higher than the rest of the yard during radiational  freezes.

 

Ed in Houston