FINAL UPDATE: 11:55 a.m. Thu 21 March 2013
If you look over the maps I posted (scroll down) going back through three day's worth of model data, you will see they are very consistent in bringing a chilly high-pressure zone down from northern Canada. A freeze is likely on both sides of the Red Monday-Tuesday morning. Normal cold spots may reach the low to mid 20s while upper 20s to around 30 will be more common.
It will be cold long enough to cause freeze damage to plants so make preparations now to protect them. Don't forget about your four-legged friends too! Here's the map from the GFS model which shows the large high pressure making for a windy and chilly Sunday:
Stay warm! - Steve
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UPDATE: Wed 20 March 2013
There's really no change to the forecast for a cold beginning to next week with a fairly high probability of a freeze Monday or Tuesday morning.

This map shows a similar result as the past few days' worth of model output: windy and chilly Sunday, with a freeze possible March 25th , 26th, or both.
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Update: Mon 18 March 2013
The models have slowed a bit on the evolution of the cold air, but the bottom line remains the same: there will be a freeze threat March 24-26 as a Canadian air mass settles over the southern Plains.
The timing of this event depends of how fast low pressure moves away from Texoma Fri-Sat; stay tuned for an update Wednesday and see maps below for a graphical overview
Low pressure provides lift and offers promising rain chances for Texoma Thu-Fri.....
The low deepens and moves eastward....and Canadian high pressure presses southward around its western side. This makes for a freeze threat March 24-26.
Take Care,
Steve LaNore
Chief Meteorologist
News 12
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.....March 15 post.....
Every year in March, Texoma gardeners and farmers monitor the weather patterns and wonder when the last freeze or frost might take place.
The average “last freeze” dates range from mid March in Sherman to April 1 in Antlers and Ada.
It looks like we will have a threat for a late-March freeze as Canadian high pressure builds southward March 21-22. The coldest air would probably be in place on the 23rd or 24th as to a morning freeze or frost.
A lot of factors come into play such as cloud cover, the depth of the cold air and the strength of the high (discussion continues below map).
However, our two most commonly used computer models agree on the timing and coldness of the air, so there looks to be the potential for at least some frost…and possibly a freeze. March 23 or 24.
So we have the luxury of time to watch it and I will post an update on Monday.
Hope you have a great St. Patrick’s Day weekend!
Take Care,
Steve LaNore
Chief Meteorologist
News 12
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