UPDATE: Mon 14 March 2011
A light freeze (or at least some frost) is possible for Tuesday morning. A milder pattern resumes beyond then into the weekend. Are we through with frost and freeze potential after Tuesday? I'm not ready to say that yet; especially while we're in a transitional pattern. One more frost or freeze is certainly possible later this month.
Remember that the average last freeze dates for Texoma are March 15-24 south of the Red and March 25-31 north.
UPDATE: Mon 7 March 2011 / 5:20p.m.
Well I’m starting to get the e-mails again with the question, “when is the last freeze expected?”
A look at the long-term data gives us March 15-April 1 as the date range during which half of the years have had their last spring freeze and half of the years have not (the definition of average applied to this case). Most of southern Oklahoma has its last spring freeze from March 25-31 while in north Texas the freeze threat ends within the period March 15-24 (discussion continues below map):
Records for late freezes extend well into April, and in fact several of the records seen below are for freezes into early May.
Record late freezes at selected cities (records not available for all locations):
A light freeze event is possible Sunday (March 6th) behind the next frontal system. Then, the models are all depicting a somewhat colder air mass moving southward from northern Canada and into Texoma March 9th.
This event presents threat of a hard freeze behind the front, with lows in the 20s area wide March 10-11. This is still a way off, but it looks probable based on model continuity and agreement with each other.
So, what about the last spring freeze? La Nina springs tend to have later freezes than average due to drier air masses in place. Given this, a freeze threat into early April is expected for the spring of 2011.
If you just want to go with the averages and forget about La Nina, odds are you’ll see a few more freezes through late March.