Tuesday, November 20, 2012

Mild to Wild


Think this weather is boring?  Hold on tight!  The pattern is just about to undergo major amplification which will lead to a very unsettled weather pattern starting next week.  It's really nothing unusual, but considering last winter was so mild and the weather this fall has been fairly tranquil, this pattern change will get your attention. 

As I write this, it's 74 degrees in Little Rock and the record high today is 79 set in 1990.  There's a very good chance we'll have a major swing in the other direction next week.

Also, keep this in mind... the lowest temperature last winter in Little Rock was 20 degrees on the morning of February 12th.  I'm NOT saying that's in the forecast right now, but it's something to watch.  Remember, I don't trust the details on long range models, but I do see a pattern developing which has real potential to deliver arctic air into the country, even Arkansas.

Many want to know what the chances for winter weather will be.  Right now, it's absolutely impossible to say that's even remotely possible.  However, meteorological winter begins December 1st and it's not unusual for something like that to happen.  Wouldn't that be a shock and extreme compared to what we're experiencing right now.

First thing, I fully expect this unseasonably mild weather to end late Thursday night into Friday morning with a strong front.  This will bring temperatures back to reality Friday and into the weekend.  Then there's more down the road.  Here are a few of the charts I'm looking at and why I'm getting pumped up about the colder pattern.  

If you're new to the weather blog, welcome.  I'm a HUGE winter weather lover and you're going to want to keep checking back for in depth weather analysis all winter long.  It's going to be fun!

This is the European valid next Tuesday morning.  Notice the closed black line in Indiana.  That's the center of low pressure with a front trailing into Arkansas.  This is another push of very chilly air moving into Arkansas.  Across the northern plains and into Canada, there's a vast cold pool of air to tap into.
Again, don't get bogged down with specifics, but here is the European model valid next Wednesday morning.  Cold high pressure located across South Dakota is bring a cold easterly wind into Arkansas.  There's also a weak area of low pressure to our west over the Texas panhandle.  This would possibly bring clouds and a cold rain to Arkansas eventually.
This is the GFS valid next Tuesday morning.  It shows the low pressure area just east of Arkansas and the front already through the state with colder air oozing into the state.

I just wanted to show you the upper level 500 mb pattern next Tuesday AM from the GFS model. You can clearly see how amplified the pattern is.  There's a huge ridge of high pressure located over Alaska.  This can and should deliver plenty of cold air southward.  Look at the vortex spinning in central Canada!  This is definitely an active pattern for much of the country east of the Rockies.

So there you have it.  Right now, I think it's safe to say the front Thursday night and Friday morning brings us back to reality.  Another cold front moves through in the Monday to Tuesday time frame.  After that, questions remain such as: how long will the cold air stay in place, does it quickly move off to the east, are there any waves of moisture further down the road.  Those questions can never be answered until we get closer to that time range.


Mitchell McDill said...

One of your fellow meteorologists said in his winter outlook not to expect any big snow events this year! I think that is a contradiction though because although the overall pattern may not favor conditions for much snow short term weather could create an event which could bring a lot of snow/sleet/ice. And the short term events are not forseeable this far ahead. Please advise all your meteorologists to keep a positive outlook for some winter wx. this year!

Anonymous said...

I dont see any snow events for ark or the mid-south to at least mid to late feb... By that time it will be hard to stick around for more then 1 day... My official winter outlook for Ark an the mid- south is on par with last winter... I see a winter with below average rainfall and a top 20 of all time record months for dec an jan... Feb will be slightly below average but not by much... I see the biggest snowfall occuring in the feb 17 to the feb 27 range of 4.3 inches in Carrol county... I see little Rock recieving a trace of snow for the entire winter.. I see a early spring on the way.....

Jason H said...

Hello all! Havent had much time to get on the blog so I thought I would stop by and give my December Outlook. Ive said many times that I dont believe in ANY outlook or forecast past 7-10 days.....ANY! Just like the experts, I do it out of fun ;-). With that being said I will give my expert outlook all Winter on the blog. Here is my December-

December 1-10 Temps mostly at or above avg. Precip above avg with heavy rain/storms possible 2nd-3rd and again 9th or 10th. No frozen precip.

December 11-20 Temps above normal. Precip above normal with 2-3 rounds of rain/storms. Light frozen precip for Northern Arkansas around 12th-14th.

December 21-31 Temps at or below normal. Precip around or slightly above avg. Watch out for our first REAL cold blast and wintry storm from dates 25th-30th.

Had fun and Ill be back for my Jan outlook......Hope snow!


NOAA Winter Guidance