Greenland Blocking Pattern

This weekend will be cold. High temperatures will be in the lower to middle 30's. This could be the coldest air of the season so far.

We will be tapping in to some of the cold air that has been rooted over southern/central Canada the last couple of days. Air temperatures have dropped to -50° in some spots shutting down airports that normally stay open all year in Canada.

A pattern is setting up that will allow cold "Arctic Outbreaks" to plunge in to the lower 48 states over the next 1-2 weeks. This is due to a Greenland blocking pattern setting up. Yes, I am talking about the Greenland in the northern Atlantic.

Below is a graphic of where the jet stream will be located this weekend. The colors under the jet stream is a representation of temperatures at 850mb or approximately 5,000 feet for Saturday.


Follow the jet stream from the Pacific all the way to just east of Greenland. See how the jet stream rises up over Greenland? That is high pressure in place over Greenland. That is going to cause a traffic jam for weather systems. Due to the ridging taking place over Greenland the jet stream gets backed up and has to go over the country. As it does so, lobes of cold air will get stuck over the Midwest and eastern United States.

Side Note: We are still keeping an eye on the upper-low that could produce snow showers around the area Friday night/Saturday. Temperatures will definately be cold enough for snow. I am a little concerned with with lack of moisture.

Wrinkle Update

Taking a look at some of the computer model data this morning. The wrinkle previously mentioned in an earlier post is still there, but a few more details are starting to emerge.

One model, NOAA's global forecast model, has taken out the wrinkle on last night's run. However, the European model still is hinting at the possibility of "something".

Perhaps I am doing a little bit of "wish-casting" because I love snow. Lets take a look at last night's European run.

Here is the chart for 6pm CT Friday. You are looking at surface pressure along with temperatures at 850mb (roughly 5,000 feet).

The surface is low well south in the Gulf of Mexico. Moisture will be streamed north from the low, but it won't be very much if any at all.

Look back to the west over Idaho, Utah, and Wyoming. See the "dip" in the black lines? This is energy coming together at 500mb (approximately 18,000 feet). This is where I am watching to see if an upper-low develops.

Here is the chart for 6pm CT Saturday. This shows surface pressure and 850mb temperatures.

The surface low has moved across Florida and is now moving out to the Atlantic Ocean. This is taking the moisture with it. Cold air begins to stream in behind the low.

Now lets take a look up at 500mb for the 6pm CT Saturday time frame. We are looking at wind speeds.

I have cut out of hole in the image. This is where the upper level low continues to develop. It is rotating through southwest Missouri at this time. This will provide some energy in the upper levels.

Here is the 850mb temps/surface pressure chart for 6pm CT Sunday.

The surface low is moving up the east coast of the US. Cold air is implanted in the Midwest. Temperatures will probably be in the 30's around southeast Missouri, southern Illinois, western Kentucky, and northwest Tennessee.

Here is the 500mb chart for 6pm CT Sunday.

I cut a hole out in the chart to indicate where the upper-low is located. Right over the Midwest. There will be energy rotating around the upper-low Saturday and Sunday.

The big question now becomes, "Is there any moisture in the atmosphere?". If there is some moisture, the upper-low could kick out some snow showers. However, as we see above, the surface low is on the east coast. The surface low is what we need to kick moisture up our way to interact with the cold air.

With upper-low situations, we often do see snow flurries or light snow showers. However, these don't turn out to be big snow producers for this area.

Again, this is only one model's depiction of what could happen. As I said earlier, the other model that looks out at this range has taken the "wrinkle" out.

At this point, I wouldn't run to Las Vegas and put money on the fact we are getting an accumulating snow for the weekend.

Stay tuned...

The core of the cold air is building over southern Canada. Last night at 10pm CT, the air temperature in Edmonton, Canada was -33°. That was the air temperature, not the wind chill. BRRR! In the above 850mb charts, you can see the cold air spilling down in to the US. One thing is for sure, it is going to be colder this weekend.

What Can You Do?

I am driving home from filling in on the Weekend Breakfast Show this morning and all of a sudden I see it. No! I can't be. Blue skies! ARGH!!!!

Why am I upset about seeing blue skies? I have been forecasting cloudy/overcast skies for today since Saturday morning. When you forecast for cloudy skies and temperatures only rising 6-7 degrees over the course of the day, sunshine is a killer.

So what is a meteorologist supposed to do? Look at the satellite imagery and see what the heck is going on. This morning all satellite imagery was showing overcast skies all the way back to Kansas and western Oklahoma. Where did the clouds go? Well here you go. Take a look at this.

Visible satellite image taken at 11:02pm CT.

Are you kidding me?!?!?!?! The ONLY hole of sunshine in the entire middle portion of the country sits right over the northern half of the viewing area. ACK!

Get Out The Ironing Board - There's a Wrinkle

For all of you snow lovers... The overnight computer models are throwing a wrinkle in the atmosphere for Friday night/Saturday morning.

A couple of the models, the European and NOAA's global forecast model, are developing a small storm in the Midwest that could bring a rain and/or snow mix to the region.

Here is what the models are showing:

First a look at the European weather forecast model. This is a snapshot of 6pm CT Saturday. It develops a surface low over northern Illinois and sucks down the cold air on the backside. This would tend to be more of a rain maker for the area.


Now a look at the GFS model. This is a look at the 850mb chart for 6pm CT Saturday. This model develops the surface low southeast of the area and develops the 850mb low over Memphis, TN. This could be more of an initial rain quickly changing over to snow setup.


It is very common to see storms develop at long range and then see them go away. However, it is interesting to note that two models hint at a developing storm at the same time period.

Is the wrinkle just a glitch in the model runs or are they on to something? Stay tuned...

A White Christmas?

The favorite questions to the weather department lately are:

1. Is it going to snow?
2. Are we going to have a white Christmas?

Answers:
1. Yes, it is going to snow... At some point this winter I think it is a safe bet. :) Oh, you are asking about the short term. I don't see any snow in our future over the next 7 days.

2. We are just now getting to the point where some of the longest long-range computer model forecasts are capturing the Christmas day time frame. As of this writing, the prospects for a white Christmas aren't looking very good. I am not seeing any significant winter storms in the forecast model December 22 through December 28.*

*Keep in mind this is a long range forecast model which doesn't have the ability to detect minute details that could evolve in to a winter storm.

Christmas weather factoids:

White Christmas:

• According to the National Weather Service the historical frequency of a white Christmas is around 15% for southeast Missouri, southern Illinois, and western Kentucky.
• The frequency of a white Christmas for northwest Tennessee and northeast Arkansas is around 6%-7%.
• The frequency of a white Christmas for central Indiana is around 20%-25%.
• The last time the southeast Missouri, southern Illinois, western Kentucky area had a white Christmas was 2004. That is when a record snowstorm hit the region dropping 10" of snow and dropping temperatures as cool as -10° at the Cape Girardeau airport.
  

The average high/low temperature for Christmas:

• Cape Girardeau, MO 42°/26°
  
• Carbondale, IL 41°/23°
  
• Paducah, KY 44°/25°
  

Noon Weather Update

To steal the line from "Good Morning Vietnam" (with a twist)... Its cold! Its dang cold!

The arctic air has arrived on cue. We have been talking about it on-air for several days leading up to its arrival. (So don't say you didn't have a heads up. haha)

*Interesting statistic: Did you know that 53% of the country is sitting under snow today?

At 12pm CT, temperatures around the Midwest range from:

• Cedar Rapids, IA 1°
• Chicago, IL 4°
• Indianapolis, IN 18°
• Mt. Vernon, IL 21°
• St. Louis, MO 23°
• Carbondale, IL 25°
• Farmington, MO 25°
• Cape Girardeau, MO 25°
• Paducah, KY 25°
• Poplar Bluff, MO 27°
• Blytheville, AR 28°

Those are actual air temperatures, not wind chills. Winds had been fairly calm this morning, but in the last 50 minutes the winds have begun to increase from Farmington, MO to Mt. Vernon, IL. Around southeast Missouri and southern Illinois wind chill numbers are down in to the single digits at times.

Now the big question, "When do we start to warm-up?". Take a look at what NOAA's Global Forecast Model is indicating. (see below)


The red line indicates air temperature. The green line indicates the dew point temperature. The green/blue vertical bars are precipitation. The grey blocks are clouds.

A couple of things to note... First, at least for me, take a look at the dew points. They are low. That is what happens with arctic air masses. Cold air doesn't hold moisture very well. That is why we get a lot of "static days" in the winter. When the cold air comes down over the north pole and through Canada it is moisture starved. There is some good news if you have been using lots of hand lotion for dry skin, the humidity should start to increase Saturday evening through Monday.

Now for the temperatures... Follow the red line (right to left). Notice daytime temperatures start to increase as early as Friday. Winds turning out of the west will help us start a slow warm-up. If we had more northerly/northwesterly winds we would continue to stay frigid. The westerly winds will flow over non-snow land whereas northerly/northwesterly winds would flow over a heavy snow pack which would keep the air cold.

If this model is to be believed, we will be in the mid-40's by the weekend and perhaps the 50's by Monday.

Yes, there is some green on the model. The GFS is hinting at rain returning to the area by Saturday evening then another round Sunday night through Monday. When looking at how much the model is pumping out only 0.11" of liquid. That isn't very much.

Before you ask, yes, there is a blue bar on the model. That would indicate snow. However, look at temperatures, you can see there is a big fall off late Monday night and early Tuesday morning. This would be a cold front moving through the area and bringing in cold air on the back side. If there is any moisture left over we could see some snow showers. However, in these scenerios, this rarely works out.

(I should note that the above model depiction is for Cape Girardeau, Missouri. Other locations will vary slightly.)

As I like to say... Stay tuned.

Personally, I like the cold air. It is winter. It is supposed to be cold. I say, "Make it even colder!" I know I am in the minority. haha I would also like to see a couple of big snow storms move through this winter. Hmm... Maybe five 10" snow's would be awesome!

Winter Storm

By now you have probably heard a lot of talk about the storm that is moving through the central United States. Yes, there will be a lot of snow and wind created by the storm, but we won't see the worst of it.

The storm continues (see surface map) to lift northeast through the US. The bulk of the energy is still back in eastern New Mexico. As the energy swings around the intensity of rain/snow will increase.


Winter Storm Warnings/Watches, Blizzard Warnings extend from Utah to Ohio/Michigan. The cold side of the storm will affect millions of people. After the storm passes, colder temperatures will start to move in. That should start to happen starting around mid-morning (5am'ish CT).


The closest snow will get to southeast Missouri, southern Illinois, western Kentucky, and northwest Tennessee will be north/northwest Missouri.

Ahead of the storm warm, moist air continues to lift north/northeast. Temperatures should rise as we go through the evening. This means we will stay all rain tonight.

The rain could be heavy at times this evening (6pm CT - 10pm CT). The latest computer model data is indicating that the rain could be out of the area by midnight tonight.

Wind Advisories are in effect from midnight through 3pm CT Wednesday for southeast Missouri, southern Illinois, and western Kentucky.

Once we get on the back side of the surface low pressure center, winds will turn out of the north/northwest and the speed will start to increase. Latest data show winds of 40mph around 700 feet above the ground. That wind will keep lowering to the surface through Wednesday morning.

I think we will see sustained winds of 25-35 mph with gusts over 40 mph. Wind should be strongest from around 3am CT to 10am CT Wednesday.

Bottom line...

1. Will we get any measurable snow? No
2. Will we get more rain? Yes
3. Will we get a lot of wind? Yes (but it could be worse)

Up, Up, and Away

In case you haven't heard yet, the US Navy Blue Angels announced they will perform at the 2010 Cape Girardeau Air Show.

The Blue Angels is the flight performance demonstration team for the US Navy. During their show, they fly six F/A-18 fighter jets.

The air show will be June 19-20, 2010. Mark your calendar and reserve your hotel room now. They will fill up FAST.

I have to give kudos to Mark Seesing and airport manager Bruce Loy for getting the "Blues" to return to the Cape Air Show for the first time since 1992. It isn't an easy task to get arguably the best flight demonstration in the world to come to your air show.

Two pilots from the Blue Angels visited Cape Girardeau's airport in November for a sight visit.

Here is video of the pilots leaving from the Cape Girardeau airport for their 40 minute flight back to Pensacola, Florida.

Full disclosure: I am a member of the Cape Girardeau Airport Advisory Board.