Monday Severe Weather Possibilities

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10 PM Thursday Update... I just crunched the numbers for March and it still looks like we'll end up as the warmest March ever in Little Rock by average high temperature and average monthly temperature.  As far as average low temperature is concerned, we'll come in 2nd only behind 1907. 

The numbers are really incredible.  Based on forecast temperatures Friday and Saturday,  we'll end up with an average high temperature this month of 76.06 degrees.  This surpasses the previous warmest March in history by 2.66 degrees (2007- 73.40 degrees).  I'm projecting the average monthly temperature will be 64.27 degrees which surpasses the previous record of 63.06 degrees in 1907.  We're living through weather history right now!


But as they say in the commercials, "BUT WAIT, THERE'S MORE".  The total rain for the month of March is 8.05''.  If we receive only .02'' of rainfall by Saturday night, we'll break into the top 10 wettest March's in Little Rock history.

For information on the possibility for severe weather next Monday, look below.  There's model disagreement, so nothing is certain at this point.
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Several days ago, I posted about the possibilities for some rough weather next week and the models continue to show that.  Meteorologist Barry Brandt always says you can count on some sort of severe weather in Arkansas around the first week in April.  Not because he wants it, but it's almost like mother nature has her own internal clock when it comes to these things.

While it's Thursday, there is soooo much that can change, but I think it would be wise to start getting the word out now that everyone needs to stay weather aware through the weekend about Monday.   Here are a few maps below.

According to the GFS run last night, there will be plenty of instability Monday afternoon.  The amount of CAPE, Convective Available Potential Energy, is more than enough for severe weather with amounts more than 2000 joules per kilogram

Notice the black closed line in OK.  This is the surface area of low pressure.  The little black lines all over the place are wind barbs which point to the direction from which the wind is coming from at the surface.  In Arkansas, it's all south and southeast.  As these winds can "back" in front of the surface low, that indicates a potential for storms to rotate and a tornado threat could become a possibility.  The warm red colors indicate temperatures.  There will be warm air in place and moisture data says plenty of fuel from the Gulf of Mexico will be present.

At the 5000 foot level winds are out of the southwest.  This brings a "turning" of the wind with height.  This shear is part of what makes tornadoes possible

This is the storm at 500mb.  This is a potent low which is takes on a negative tilt.  This bundled piece of energy over Oklahoma will provide the spark to ignite the storms with an environment in place which is conducive to some very rough weather.  THAT'S IF THIS MODEL VERIFIES. REMEMBER, MUCH CAN CHANGE AND I HOPE IT DOES, BUT THIS IS CLIMATOLOGICALLY THE FAVORED TIME OF YEAR FOR THIS TO HAPPEN SO STAY TUNED!!!!!!!!!!!!!!!!!

Changes On The Horizon?

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What a week this is so far and there's more to enjoy!  I wouldn't know though.  Andria and I are in the middle of remodeling our master bedroom and bathroom.  I've got all the windows open so I can enjoy the fresh air, but there's no getting around it, it's work!  I can only do so much as a "handy man". I can paint, install a few things, etc. but professionals are going to have to come in and do the rest.  It's really not a big job, but enough to update it!  I don't think the walls have been painted since the house was built and a new coat is making all the difference.  Blake wants to help and points out if I miss a spot.

Back to the weather.  As I said in the previous post, this week will feature near record breaking warmth with Wednesday and Thursday the most likely days in Little Rock to establish new daily record high temperatures.  By the end of the month, March 2012 will go down as one of the warmest ever in Little Rock weather history by average high, low, and monthly temperature.

Next week looks very different and active with details still to be sorted out.  Meteorologist Barry Brandt has always said that you can usually count on some sort of severe weather the first few days of April.  He's not wishing for it, it's just the reality of living and Arkansas and the time of year.  I think it's very possible to deal with some rough weather next week followed by a cool down.  The models are hinting at some chilly air trying to get back into the pattern.  When I say chilly,  I'm comparing it to where we have been.  While it's in the long range, I think it's possible to see average or slightly below average temperatures for a day or two.  What we are experiencing right now is "off the charts" warm!

Check out the maps below...

This is the overnight run of the GFS at 500 mb indicating a strong area of low pressure closing off just west of the state.  This would bring bring rain and storms next Monday and Tuesday.  Remember, DON'T TRUST THE DETAILS, but look at where the weather pattern is heading.  The ridge of high pressure in control this week will be replaced with the influences of a trough of low pressure.... UNSETTLED.

This is the Monday evening run of the GFS at 500 mb showing a potent low in the plains with a negative tilt to it.  This means the axis of the trough is oriented from southeast to northwest.  This vigorous area of low pressure would bring a round of rain and thunderstorms with it.  AGAIN, DON'T TRUST THE DETAILS!!!!!!!!  JUST NOTICE THERE IS CONSISTENCY WITH A STORM SYSTEM TO OUR WEST.  HOW IT AFFECTS OUR WEATHER IS NOT KNOWN YET!

This is the overnight run of the European model showing a blocking pattern setting up.  This is the 500 mb pattern.  Notice the trough off the west coast, then a ridge over the western United States into Canada and then a strong trough over the central United States.  This would bring much cooler air into the state if it verifies by the middle of next week.  HOWEVER, THE EUROPEAN MODEL HAS BEEN ERRATIC IN THE LONG RANGE, BUT LET'S WATCH IT!!!!!!

Record Breaking March!

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It looks like winter contest #1, which I extended until the end of March, will not have a winner.  I'll keep the prizes and give them away in the summer contest.  Stay tuned for that.

As we mentioned here on the Arkansas Weather Blog a couple of weeks ago, this month could be record breaking.  With only a few days left, it looks very likely March 2012 will easily make it into the record books!

I keep getting asked if that means we'll have a very hot summer.  Actually, there's no connection between the weather now and what could happen down the road.  For those of you who read this blog regularly, I don't like long range forecasting.  I have seen more wrong than right.  With that said, weather patterns can easily change.  For instance, look at the winter of 2010-2011.  We had record breaking cold and snow, then the following summer we experienced record heat.  Remember early last August when Little Rock soared to a record breaking 114 degrees and Fort Smith put together a record breaking stretch of 100 degree + temperatures?

I have seen some long range forecasts for the summer months which indicate it will actually be a cooler and wetter summer than the past 2.  Take that with a grain of salt though and hope that actually happens.

This week will feature more warm weather and records will be challenged.  Here's a list...


Monday 85 (1907)
Tuesday 87 (1895)
Wednesday 86 (1907)
Thursday 85 (1974)
Friday 86 (1963)
Saturday 91 (1974)

Here are a few graphics showing where we stand in terms of a record March and what I'm projecting by the end of the week.

If March ended Sunday, this would be the warmest March in Little Rock weather history in terms of average daily high temperature.  Records date back to the 1870s.  I see no reason why that should change with more warm weather in the forecast.

If the month ended Sunday, it would be the 5th warmest in terms of average daily low temperature.  Since readings will be above average all week long.  I'm projecting we'll finish 2nd in this category.

If March ended Sunday, it would be the 2nd warmest March on record in terms of average monthly temperature.  This is combination of the average high and low.  Based on our forecast through the end of the month, I think we'll likely end up as the warmest March on record by average monthly temperature.

Hail, Cold Air Funnels, Total Rain, and Record Warmth!

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Think the weather is boring?  Think again.  There's still so much going on with our weather, it's hard to come up with a title for this post!

Let's start out with what will happen later today.  The cut-off low will move through the area sparking off showers and thunderstorms.  This is basically a pocket of very cold air aloft which is very conducive to the development of showers and thunderstorms.  This is the type of situation which is favorable for the production of hail with the super cold air above our heads.  The most likely locations will be western and northern Arkansas.

Also, there has been a lot of talk about "cold air funnels".   These are usually harmless and very rarely make it to the ground, but can cause some to get nervous.  When a closed, cold core system like the one we have traverses overhead, it's something to watch!  Basically, with plenty of spin associated with the upper low, an updraft into the cold air aloft can begin to spin and the formation of a condensation funnel can appear.  These usually occur well above the ground, but are visible.  It will be interesting to see if any form.

Here's a visible explanation.

From the National Weather Service in Ohio.  Some of these cold air funnels will be possible close to the upper low in western and northern Arkansas

Now onto the total rainfall amounts.  The much talked about rainfall gradient was amazing to see.  While Little Rock and Pulaski county saw close to 5'' of rain, just 40 to 50 miles east on interstate 40, there wasn't much at all.  The north/south oriented, slow boundary kept the rainfall from moving east for a long time.

Doppler radar estimates show central and western Arkansas receiving 3-6''.  Look at eastern Arkansas.  Only 1-2'' fell.  That's pretty amazing to see!

These are official 48 hour amounts ending Thursday morning around 6 AM.  These are NWS official rain gauges.  Little Rock received 5.09'', but Searcy only got 1.55''.  Amazing!!!!

Despite the rain and cooler temperatures, Little Rock is well on its way to a record breaking March.  With plenty of warm weather in the forecast next week, this is ALMOST a done deal.  We will more than likely end the month in the top 10 warmest March's in Little Rock weather history which dates back to the 1870s.

By average high temperature, as of Wednesday, that number is 74.48 degrees.  That means if the month ended today, it would be the warmest March by average high in weather history for "The Rock"

By average low temperature, as of Wednesday, the number is 50.81 degrees.  The makes this month the 6th warmest by average low temperature.  Here's a list of the top 5.
1) 1907 - 54.00 degrees
2) 1921 - 52.23 degrees
3) 1908 - 51.52 degrees
4) 1910 - 51.32 degrees
5) 1938 - 50.87 degrees

By average monthly temperature, as of Wednesday, the number is 62.64 degrees making it the 2nd warmest in Little Rock history.  Number 1 on the list is 1907 (63.1 degrees).  I think it's entirely possible to be number 1 in this category by the time the month is over.  I'll keep you updated!

Flash Flooding Wednesday and What's Ahead

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12:30 PM Wednesday Update...  The National Weather Service says it was straight line winds that caused the damage Tuesday in Morrilton.  Those winds were estimated at 80 mph.  This is just another example why severe thunderstorms need to be taken seriously as they can cause damage just like weak tornado.  In 2011, severe thunderstorm winds killed 7 people in Arkansas.

I'm still watching for the possibility for some strong and maybe severe thunderstorms late Thursday as the area of low pressure aloft makes a move to the east.  SPC does not have a slight risk out yet, but I think they might.  This cold pocket of air aloft will be supportive for some hail producing thunderstorms especially in western and northwestern Arkansas late Thursday.  I don't think it will be widespread, but it's something to keep an eye on.

I have flooding and damage pictures on my facebook page if you want to check that out.

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I think the forecast has worked out quite well so far.  As of Wednesday morning, amounts are ranging around 4-5 inches in many locations. I talked several times about the rainfall gradient being sharp and it truly is.  You can see in the map below.  I think the rain will continue today into Thursday morning for the state with an additional 1-2'' possible.  The rain which is oriented from the south to the north will become oriented from the southeast to the northwest tonight and Thursday as it makes its slow push to the east.  This is due to the circulation around the upper low.  I'll explain below.  A quick look at the long range models next week shows well above average temperatures and mostly dry conditions.  This will lead to the end of the month and I still think it will end up as one of the warmest March's in Little Rock weather history.

Also, there was some severe weather across the state Tuesday.  Mostly thunderstorm wind damage.  However, there was 1 tornado reported in northwest Arkansas Monday night which brings the state total this year to 8.  Average is 33.

Amazing rainfall gradient where central and western Arkansas has received 3-5''.  If one travels just a little down interstate 40, it has barely rained... YET!

This is the NAM simulated radar late this afternoon into the early evening.  Notice the circulation around the low which is centered in Oklahoma.  The rain band across Arkansas is more oriented from the northwest to the southeast and pushing out of central Arkansas.

The overnight run of the NAM is developing some thunderstorms with the upper low as it makes a move to the east.  This is valid Thursday evening around 10 PM.  Some of those storms could contain heavy rain and I wouldn't be surprised to see some hail out of that.  Not set in stone, but I'm watching it!

A Wall of Water Advances Eastward

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I saw a tweet from meteorologist Barry Brandt calling the rain in eastern Oklahoma and western Arkansas, "a wall of water."  I think that's a great description of what's heading our way later today into Wednesday.

When I went to bed last night, the rain was barely into western Arkansas.  When I woke up, it had moved only about 25 miles to the east.   This extremely slow movement and copious amounts of moisture due to the cut-off low is causing the flash flooding in eastern Oklahoma.  As of Tuesday morning, rainfall amounts are around 3-6'' with isolated higher amounts with several roads closed in eastern portions of the Sooner state.  This will make very, very slow progress to the east today.  While showers will be scattered around today, the heavier and steady rain will start in central Arkansas late in the day into Wednesday.  A flash flood watch is in effect for most of western, central, and southern Arkansas.  This includes the Little Rock metro area.

I've said it once and I'll say it again and again, the hilly terrain of western Arkansas will cause rapid runoff into streams and rivers.  Spring break campers and hikers need to be alert or rearrange their plans!

There will be a risk for severe weather as well.  This threat is low compared to the flooding aspect.  However, some storms may contain hail and gusty winds.  An isolated, brief tornado can't be ruled out.

HPC shows rainfall amounts exceeding 5'' for most of the western half of the state.  The sharp rainfall gradient continues to look like a reality.  Eastern and northeastern Arkansas will see lesser amounts.

Remember, this is only a model, but it shows LR receiving 3.4''

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Most of central, western, and southern Arkansas is under a slight risk for severe weather.  The main threat will be wind and hail.  A brief, isolated tornado can't be ruled out.

The significant river flood outlook shows most of the rivers and streams in Arkansas could experience flooding.  It's either likely or possible according to this source.

Complex Storm System Brings Flooding/Severe Threat

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6:50 PM Monday update... Not much has changed with my thinking on how this unfolds.  The rain is already coming down across eastern Oklahoma with numerous reports of flooding.  I still think this area of rain will slowly creep to the east and will not arrive in central Arkansas until Tuesday afternoon or evening.  There could be a few showers here and there, but the bulk of the heavy rain will wait until that time.  Western Arkansas continues to be the target for the flooding rainfall starting tonight into Tuesday.  I have read some reports that a few campsites have been temporarily closed anticipating the flooding threat.  I think that was a very smart move.  As the WeatherNinja and I have been talking about, the campers and hikers really need to pay attention to the weather or just plan a trip some other time.

Here are a few of the latest maps from Monday afternoon.

The afternoon run of the NAM shows the highest amounts of rain for western Arkansas with a very sharp gradient the further east one goes.  It's really amazing to see how strong it is.  While some places could receive more than 5'', just 50-100 miles to the east may only get an inch or two.

The afternoon run of the GFS shows heavy rainfall all the way into central Arkansas.  If this looks like it could verify, the NWS would more than likely extend flash flood watches to the east.

HPC's latest rainfall forecast indicates more than 5'' across a large area of western, central, into southwestern Arkansas.  This is total rainfall through the entire event.

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To say this storm system is complex with uncertainties is an understatement!!!! As you know by reading this blog, "cut-off" lows are tricky to predict and it's important we get this as right as possible when it comes to forecasting due to the potential for very high amounts of rainfall.  These lows wobble around when they are cut off and the models handle them poorly.  The one thing we are confident in right now is the high risk for flash flooding across northeast Texas, eastern Oklahoma, into western Arkansas.

Remember, we talked about the rainfall gradient?  The data continues to show there will be a very significant one across the state. This means there will be a very noticeable difference in rainfall amounts over a very short distance from west to east.

While we could get a few showers in central Arkansas today and Tuesday, the heavy and steady rain may WAIT until late Tuesday into Wednesday morning in the metro.  The timing and and placement of these storm systems are tricky so this can change.

There's also the severe element that I'll watch.  Early Monday morning, the Storm Prediction Center placed a very small portion of western Arkansas under a moderate risk for severe weather.  The main threat will be hail and wind, but an isolated tornado will be possible.  The main threat to the remainder of western Arkansas will be heavy rain.

This is spring break.  Please get the word out to anyone spending it outdoors in western Arkansas that they need a NOAA weather radio or maybe even rearrange their plans.  Late this week into the following week, we'll watch rivers rise as water drains out of eastern Oklahoma into Arkansas.  It will be interesting to watch the Arkansas River here in Little Rock and downstream.

Check out the maps below to see all the complexities with the data.

This is the overnight run of the GFS.  Look at the 5''+ amounts across the western half of the state through Thursday.  Also, notice the very sharp rainfall gradient.  The GFS shows it over central and eastern Arkansas while other models have it further west.  The higher elevations of western Arkansas will get the brunt of the rain meaning runoff will be high into creeks, rivers, and streams.  Campers and hikers beware!

The NAM out to Thursday shows the highest rainfall amounts further west over western Arkansas and eastern Oklahoma.  Totals, according to this model, will decrease significantly according to this model so you see the uncertainties.

Our own model, Futurecast, also shows the complexities and uncertainties.  The one thing all the models agree on are the high rainfall amounts across western Arkansas.  This shows 5-7'' in that area of the state.  However, look how much they drop off the further east.  REMEMBER, THESE ARE MODELS AND NOT FORECASTS!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The SPC has placed a very small portion of western Arkansas under a moderate risk for severe weather.  This includes towns like Mena and DeQueen.  The main threat will be hail and wind, but an isolated tornado can't be ruled out later Monday into early Tuesday morning.

This is courtesy of the National Weather Service office in North Little Rock.  This is their thinking right now which is in line with some of the model data I posted above.  Here's a link to their site.  http://www.srh.noaa.gov/lzk/

Spring Break Soaker Update

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There are still some uncertainties when it comes to the forecast as this intense area of low pressure slowly inches towards Arkansas.  As you know, this will be "cut-off" from the main jet stream flow.   How much rain falls if a function of where this low tracks and at what speed.  The data over the past 24 hours has trended towards slowing down the storm system and cutting it off further to the south and west.  This trend continues to show a high chance for very heavy rainfall, especially for western Arkansas.  The slow movement to the storm system means it will take awhile for central Arkansas to see the rainfall.  The heavy rains should reach our portion of the state either Tuesday afternoon or even as late as Tuesday evening.  As this low moves to the east, the rainfall amounts will lessen as you head towards the Mississippi River.  While amounts could be significant there, it won't be as much as western areas of the Natural State.  There will be a very noticeable rainfall gradient across the state.  This means the amounts will change greatly in a short distance as one travels from west to east.  Where this gradient sets up is dependent upon the track and speed of the storm system.

Because the rainfall will occur over the hilly terrain of western Arkansas, rapid runoff into streams and rivers could be significant.  Since it's spring break, please get the word out to campers and hikers they need to be weather aware or rearrange their plans.  One other item that needs to be discussed is the downstream effect of heavy rainfall along the Arkansas River.  Much of this will fall in eastern Oklahoma into western Arkansas causing the river to rise eventually.

Check out the maps below.

HPC is forecasting amounts near 8'' along the Oklahoma/Arkansas border.  Notice, there is a very strong rainfall gradient.   This means there will be  a large rainfall difference from west to east.  Where this gradient sets up is dependent upon the track and speed of the storm system.

This is just showing you the 5 day rainfall map above with contours.  Notice the sharp rainfall gradient from west to east.

The NAM simulated radar valid late Tuesday at 7 PM.  According to this one piece of data, the heavy and steady rain is just entering the metro area.  Again, this is only one piece of data and the timing can change.  Eastern areas of the state may have to wait until later Tuesday night and Wednesday for the rain.

Through 7 PM Tuesday, the accumulated rainfall will be highest according to the NAM across OK, TX, and far western Arkansas.

By Wednesday at 7 PM, the GFS shows a dry slot pushing in from the southwest.  That's what you see in the purple.  The blue areas contain the highest moisture.  With the counterclockwise rotation around the system, which is located over Texas, it's entraining a punch of dry air.

By Thursday 1 PM, the dry punch is affecting most of western Arkansas with the rainfall across eastern portions of the state where you see the higher moisture values in blue.  The storm is centered over TX and OK, but should lift to the north and east.  Rainfall will be decreasing at this point!

Spring Breakers Deal With A BIG Wet Weather Maker!

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We're all going to have to deal with this, but I really want to communicate the message to anyone who has outdoor plans that this could turn into a serious situation.  Thanks to the WeatherNinja for pointing this out to me Saturday.  There will be many campers, hikers, etc across the state that need to have a NOAA weather radio or even consider other plans.  It appears the heaviest rain will fall across western Arkansas which as you know is a very hilly area of the state.  This will contribute to more runoff into streams and rivers causing a possible rapid rise in water levels.

As we have talked about here on the Arkansas Weather Blog for more than a week now, this intense storm system means business.  It will be a very slow mover as it cuts off from the main jet stream flow.  This slow movement will produce copious amounts of rain over the same areas over a 2 day period.  We are hoping this system speeds up and limits the amount of rainfall, but these cut off lows are often difficult to pinpoint the exact track and speed. Even at this time, there are still disagreements with various models as to where the axis of heaviest rainfall will set up.

There will also be a severe element to this storm system, but I think the flooding threat is much higher.  The Storm Prediction Center has placed portions of Arkansas under a slight risk for severe weather and I'll explain below.

We are not expecting this rainfall to start until Monday night into Tuesday and Wednesday.  Remember, turn on your NOAA weather radios and/or sign up for WeatherCall 7.

Below are a few maps explaining the situation.  I'll keep you updated!

The NAM model is much slower and shows total precipitation amounts more than 5'' in some sections of western Arkansas.  Notice the very sharp gradient between the heavy rain and lighter amounts.  This is the only model I have seen doing this, but it's worth watching.  If you believe the NAM, rain won't really start in central Arkansas until Tuesday afternoon.

This is the midday Saturday run of the GFS showing the axis of heaviest rainfall across eastern Oklahoma into western Arkansas.   However, this shows several inches in central and eastern Arkansas as well.  So you see there are some disagreements in the short range at this point.

The late Saturday run of the GFS shows the axis further to the east with 5'' + across the majority of Arkansas.  The GFS is having a tough time with each run pinpointing how much rain will fall.  Like I have said, it's not a matter of if it will rain, but how much?

The next run of the GFS Sunday morning shows the axis back over eastern Oklahoma into western Arkansas with a sharp gradient across central sections.  Lighter amounts are forecast the further east you go, but it could still be significant.  Once you have examined all the data, you can clearly see the consistency of heavy rainfall for western Arkansas.  That's the area that concerns me.

This is the official guidance from HPC showing 8'' + for western Arkansas over the next 5 days.

The Storm Prediction Center has outlined the western half of Arkansas, including Little Rock, for a slight risk of severe weather late Monday into Tuesday.  The main threat will be hail and wind.

The threat continues into Tuesday, especially for portions of central and southern Arkansas.  Remember, it's only slight.  The area is much smaller with hail and wind the main threat.  As I said above, I really think heavy rainfall will be the bigger story.  I'll keep you updated!

Possible BIG Rain Event Next Week

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12:45 PM Saturday Update... I have been in the process of reviewing the latest model data and I still have some uncertainties next week.  First of all, I axis of heaviest rainfall isn't set in stone, but it appears eastern Oklahoma into western Arkansas will see the most.  The HPC says 7'' will be possible in this location.  Do I buy that? While it's completely within the realm of possibilities, I'm a bit skeptical.  Again, this all depends on the speed of the system.  If it takes a slow approach, yes, that amount will be possible.   If it speeds up, those amounts will not be realized.  This is a not a matter of "if it will rain?", but "how much will it rain?"  At this point, I think it's safe to say western Arkansas could see 3-6''.  As we get closer, we'll nail down the details.

One other aspect to the system will be the severe weather potential.  It's there, but I think the potential for heavy rain and flooding will be higher especially since the rain will fall across hilly terrain.

As this area of low pressure aloft cuts off and meanders through the mid south Wednesday and Thursday, there will be a pocket of very cold air aloft.  I'm also going to watch for the potential for widely scattered thunderstorms if any surface heating can take place.  In this situation, these storms would produce hail. Right now, the models show very little in the way of instability, but it's something worth watching.  There's so much on the table to watch with a system like this and I'll do that for you right here on the Arkansas Weather Blog.
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As you know, I have been keeping an eye on an incredibly strong area of low pressure aloft which will affect the plains into the mid south next week.  While severe weather will be possible, the bigger threat may end up being very heavy rainfall.  The specifics can't be answered yet as this is still in the long range, but I think it would be wise to start talking about it now especially in light of what was released from the National Weather Service recently.  While, it's too early to predict the severity of the rainfall, keep in mind Arkansas ranked #1 in the nation for flash flood fatalities in 2011.  The National Weather Service has run a campaign over the years called, "Turn Around, Don't Drown."  Many of those fatalities were due to drivers trying to cross flooded roads.

Many uncertainties still exist as this event unfolds next week.  We still don't know where exactly the axis of heaviest rain will set up and how fast the system will move.  Obviously, the slower the system, the heavier the rainfall amounts will be.  As intense as this storm will be, there's an equally intense area of high pressure in front of it which should make it a slow mover.  We really need this to speed up and keep the heavy rainfall to a minimum.  Only time will tell as the models get a better handle on the situation.

The next four maps are from consecutive runs of the GFS showing how difficult it is at this point to predict where the heaviest rain will occur.

The 00Z run of the GFS  from Friday shows the axis of heaviest rain across eastern Oklahoma with amounts more than 5 inches.  The amounts decrease the further east you go.

The 06Z Friday run continues to show the axis of heaviest rainfall across eastern Oklahoma, but increase amounts over Arkansas.  IF this verifies, we're talking about 3-5 inches.

The next run of the GFS (12Z) shows the axis of heaviest rainfall now over extreme eastern Oklahoma into western Arkansas.  If this verifies, we're talking about amounts in excess of 5'' in a hilly area of the state.

The 18Z Friday run of the GFS now shows more of eastern Oklahoma and much of Arkansas with 5'' or more of rainfall next week.  Now you see the forecasting problems and this is just 1 days worth of model information from the Global Forecasting System.  Like I said above, knowing where this axis sets up is uncertain.  Also, if the speed is faster, the amounts will be less.  If the low moves slower, the amounts could be more.

The official forecast from HPC shows 5'' or more from northeast Texas into western Arkansas.

You're looking at the 500 mb pattern from the NAM late Sunday.  Notice the area of low pressure moving through the western United States.  The high dominating our weather will ease to the east.

This is the GFS early Wednesday morning.  Notice the area of low pressure aloft is cut off over Oklahoma.  When this happens, they can become very difficult to predict.  As along as it stays west of the state, we will have the threat for heavy rainfall and thunderstorms.  Again, we hope it speeds up.