Sunday, July 22, 2012

Here and There

(post by Jason) They say that when you write or speak everything you say is biased based on your own previous assumptions and experiences. That's probably true, and it's certainly true when it comes to trying to write objectively about the temperature climatology here in southern Middle Tennessee. If you've lived your whole life in Miami and you enjoyed the experience then you will rightly think that our winters are cold.  But Miami is a long way from Central Ontario where I grew up.  At the end of this post I compare some climate data between middle Tennessee and Central Ontario.  The differences are striking.

Middle Tennessee definitely experiences all four seasons. Typically, winters are cool and wet with lots of rain and very little snow. Winters here are not long and they are not severe. By the calendar, winter here starts between Thanksgiving and Christmas and persists through some or most of February. Winter is by far our most variable season. One day it may be 40 degrees and pouring rain and the next it may just as easily be 65 and sunny. There are several days during each winter month where it is possible to work in shirtsleeves. For gardeners there is something growing and blooming in this part of Middle Tennessee in every winter month.

Spring in this part of the world is delightful and it is a long, pleasant season. Some time in February the cool season grasses begin to green up, the early flowers start to bloom and the sun gains a spring like warmth that persists through March, April and often well into May. Spring days here are usually warm and sunny but spring nights stay surprisingly cool. We often get some late radiational white frosts, often well up into April when daytime temperatures are usually in the middle 70's and sometimes on the cusp of April and May when typical day time temperatures flirt with 80 degrees. That said, it's rare to have a damaging freeze occur later than the last week in March.

Summers here are long, warm and humid. Typical summer conditions persist from mid May through mid to late September and once summer gets here it usually means to stay. Summer is by far our longest and most stable season in terms of temperature. With the exception of a few weeks in July and August it is typically quite pleasant and tolerable.

Fall, like spring, is a long, pleasant transitional season. Some time in late September the humidity will drop and nights will get considerably cooler, though days remain at or over 80 degrees into October. Pleasant weather typically persists through all of October and November. We might wake up to a light white frost in late October or early November but plant killing hard freezes usually wait until nearer Thanksgiving before making an appearance.

I'm kind of a weather statistics freak and thanks to  Environment Canada I was able to look up a hundred years worth of climate data for several climate stations near where I grew up and compare it to our nearest climate station with lengthy temperature records. Here is an extrapolation of the data:

Average hi/lo Temperature in Jan  25/6    
Average hi/lo Temperature in July 79/54  

Average Last frost May 18
Average First frost Sept 23

Days with Minima Below 32 degrees (true freeze) - 172 (Melissa here; basically half the year with days below freezing? I think I would just die.)
Days with Minima Below 36 degrees (ground frost)- 198

Average annual snowfall:  85 inches (Melissa again. 85 inches of snow?  It is official, I would die.)

Compare this with a hundred years worth of data from our nearest TN climate station:

Average hi/lo Temperature in Jan 50/28
Average hi/lo Temperature in July 89/68

Average Last Frost April 5
Average First Frost Oct 27

Days with Minima Below 32 degrees - 74
Days with Minima Below 36 degrees - 89

Average annual snowfall:  2 inches (Melissa one last time.  This is almost more than I can deal with!!)


Grand and Elfin doing their morning routine - staring us down waiting for breakfast

Lightening, Snappy, Thor and Fabrizzio

Hemi resting his head on Thomas

Maisie having some pony time with Cuff Links and Traveller

grey horse club; Gus, George and Asterik

Homer and Moe

Chance, Leo and Levendi

Kennedy, Clayton and Stormy

1 comment:

Bif said...

Certainly interesting. It kind of makes me want to move south...