Monday Afternoon Discussion

The cold front has pushed completely south of the area, and the results have been spectacular weather for July. Dewpoints in the mid 50s (very dry for this time of year) and light northerly winds have made for a beautiful and low humidity day. But enough about now, what about the week ahead?

Essentially the weather will be the same. Sunny, dry, and gradually warming up.


The 12z GFS model run showing 2m temps and surfaces winds valid at 1 am Wednesday morning shows high pressure over the Ozarks, giving us clear skies and still relatively dry air. Bertha continues to meander through the Atlantic, pestering Bermuda with high surf and occasional rain squalls. The main precipitation area will be confined to Florida (sea breeze thunderstorms) and the Upper Midwest/Plains (where the jet stream is). Bertha will wander around before finally pulling north-northeast and away from Bermuda.

Looking into the GFS crystal ball:


This is the 500mb chart of the 12z GFS valid at 7 pm Tuesday, July 29. A trough is centered across the East and Northeast. That X centered near Sikeston ad the MO/IN/KY border is an impulse of energy riding the flow aloft. If we look at the surface features...


We see a typical summertime pattern with scattered thunderstorms across the Southeast, with the disturbance aloft enhancing rains in the afternoon hours. At the surface, the general flow will be from the south, so moisture would certainly be in place. For us, we would be on the back side of the trough, limiting our rain chances. But again, with the flow at the surface coming out of the tropics (see all those winds from the Atlantic/Gulf moving west and then north?), we can expect the summertime storms in the afternoon hours.

Tomorrow, weather across "The Pond" as the British Open starts Thursday.

Early Evening Radar

Saturday Afternoon Map Discussion

The two H's have dominated the weather here in the Mid-South lately. HOT and HUMID. Dewpoints in the low to mid 70s are putting the heat index in the 100-105 range for today. Having been outside today, I can tell you it is definitely humid. That humidity will lead to rainfall as we head overnight and into tomorrow.



Above is the 12z NAM model valid at 10am, and it clearly shows the cold front moving through the region. Expect some heavy rainfall out of this frontal passage - on the order of one half to one and a half inches. Much drier air will push into the area, and overnight lows at the beginning of the week may dip down into the upper 50s in some locations. The humidity will slowly creep back up throughout the week, so the air will feel more and more sticky as the week goes on.

That's all for now. Crystal ball discussion later.

Wednesday Afternoon Radar and Map Discussion

Let's first take a look at the radar at 3:56 CDT:

Let's take a look at the weather for tomorrow, courtesy the 12z NAM model run valud at 1 pm Thursday afternoon:

I've drawn in three items of note. First, the monsoon season is underway across the desert Southwest. That's evident with the surge of moisture. The cold front producing activity here today will continue to sag through the area tomorrow, keeping rain chances in the forecast. A second front is taking shape across the Midwest. That will move in over the weekend. With the old front hanging around and the new front set to move in, expect scattered to isolated thunderstorms the remainder of the week.

That's all for now. More later.

Summer Storms and Outflow Boundaries at Work

Check out the two radar images below (courtesy Wunderground):


Now look at the radar 8 minutes later:


Notice how quickly the storms in Fayette County grew along that outflow boundary.

More information on outflow boundaries can be found here.

Model discussion tomorrow.

Saturday Evening Radar Update

Some people have seen quite a bit of rain the past couple days. That is a good thing as it has been dry recently. Expect more of the same tomorrow, though the overall coverage should be smaller than today. We'll dive into some model runs tomorrow.

Saturday Mid-morning Radar

Expect isolated thunderstorms to continue to pop up across the area as the heating of the day kicks in, and any outflow boundaries in the area may activate. Today will not be a wash-out.

Fourth of July Midday Update

Will it rain today?

July 4th Morning Update

The radar and notes provided pretty much tell the story. Have a great day today, and if dark skies move in, head inside and let the storms pass. Lightning is not something to mess with.

Wednesday Evening Map Discussion

Zzzzz... that's been the weather so far this week. That continued today, where highs ranged from upper 80s to low 90s. Changes are on the way though, as a cold front again will begin to slide into the area.

Here's a look at the 18z NAM model valid at 7 pm July 4th:

I've drawn in the location of the cold front with a gray/grayish purple line to our north. This will be close enough to kick off mainly afternoon and early evening thunderstorms. At this time, there will no widespread severe weather, but there will be locally heavy rain and frequent lightning. Keep an eye to the sky as your festivities get going in the afternoon. When you hear the thunder, it's time to move indoors.

The second item I've circled is a blob of tropical moisture in the western Gulf of Mexico and Bay of Campeche. We'll have to keep an eye on that to see if it moves inland, which would lead to more numerous showers and thunderstorms.

Next update comes tomorrow evening.

Friday Afternoon Map Discussion

Hot and humid. That’s the weather for today. Mostly sunny skies will allow for 92-94 degrees for the high.That’s the weather now. How about this weekend?

12z NAM model valid at 4 pm Saturday:
(*Model maps courtesy wunderground.com*)


It looks like the front has increased in forward speed a little bit from yesterday’s models. The big low pressure over the Minnesota/Wisconsin/UP of Michigan border will drag down cooler air behind the front. It looks like we will not see much rain tomorrow afternoon, but with humidity in place and a lifting mechanism nearby (the front), expect summer pop-up storms to be more frequent.

12z NAM model valid at 1 am Sunday morning:


Showers and thunderstorms will weaken slightly overnight without daytime heating. Still, with the front moving into the Mid-South, showers and thundershowers will take place. One small note, the GFS is slightly slower with the frontal passage than the NAM. Does this mean Sunday will be a washout? No, but storms may hang around longer than the NAM would indicate.

12z NAM model valid 1 pm Sunday:


The front is moving into central Mississippi at this time. The GFS hangs the front back across north Mississippi. A slower solution would keep rain chances in our forecast through midday, while the faster solution the NAM currently has would clear things out by mid-morning.Early next week: Calm weather with slightly below average temperatures. We’ll be in a northwesterly flow aloft. If enough moisture returns, any ripple of energy in that flow could trigger scattered/isolated storms.

That’s all for now. Have a great weekend!

Thursday Afternoon Map Discussion

I thought for today we would take a look at the progression of model runs valid for the same date and time and see how they change as new data comes in. Each model is valid at 7 pm Friday evening.

Let’s start with the 18z GFS from June 25:


This places the front from roughly Kansas City to Chicago, curving back into Canada. A lot of moisture is in place across the Southeast from the high pressure brining in a southerly flow. The heaviest rain looks be across central Alabama and the Kansas/Missouri border.

Now here’s the 0z GFS from June 26:


Its precipitation coverage is significantly less than the 18z run. It still has moisture present across much of the Southeast, but the heaviest rainfall now is over the Florida panhandle. The front is in the same area as the previous run.Now the 6z GFS from today:Again even less precipitation than the 0z run. The heaviest rain continue to remain along the Gulf Coast states. The front remains across the Midwest.

Finally, the 12z run from today:


A big bulls-eye of rain over the big bend in Florida. The front again sits in the same region. Scattered/isolated showers and thunderstorms will be expected around the Mid-South.

While we’re looking at models, check out the 12z run valid at 1 am Sunday morning:


A very strong complex of thunderstorms is ready to blast through the Mid-South, dumping up to 5 inches of rain. Now the GFS tends to overdo precipitation amounts, but at this point, severe weather potential needs to be monitored all along the front. Late Saturday night into Sunday morning appears to be our best chance at significant rain. Until then however, the pop-up summer storms are possible anywhere across the area.

The next update (hopefully) comes tomorrow afternoon.

Wednesday Afternoon Map Discussion

Good afternoon once again weather geeks. We’re continuing with the hot and humid weather this afternoon. Mid 90s with heat index values nearing 100. It will be hot. But enough about the now? What about the rest of the week?

12z NAM model valid for 7 pm Thursday evening:

There are a few things to notice here. First, there is a surge of moisture in the Gulf of Mexico coming north that will help increase coverage of rain in the Southeast by the weekend. There is no tropical worries with this, just moisture pulled north from tropical waves not expected to develop. While not a drought-busting event, this could provide some very beneficial rains. Second, a complex of thunderstorms looks to be moving across Iowa, where it is NOT welcome. That complex will be a precursor to the third item of interest – the trough set to dig in across the eastern half of the nation. Elsewhere, the model shows the garden variety summer pop-up storms across the Southeast. Let’s move forward to the weekend.

Again the 12z NAM model valid at 7 pm Saturday evening:

Low pressure is centered over the Minnesota/Wisconsin/Canadian borders. The cold front stretches from Michigan to Texas. Ahead of that front showers and thunderstorms will develop and push eastward. That tropical moisture looks to be enhancing the activity over Alabama and points northward as it gets funneled up ahead of the front. Saturday will be our best chance of rain in the Mid-South. Beyond, the front does not bring a significant drop in temperatures but perhaps lower humidity values.

Crystal ball land: No graphics today. The 12z GFS has a dry Fourth of July. The long-range does indicate the Bermuda high anchoring in, which would lead to a southerly flow and isolated/scattered afternoon thunderstorms.

Same place, same time, new post tomorrow.

Tuesday Afternoon Map Discussion

A return to heat and humidity is underway across the area as the trough across the East lifts out to the Atlantic. This will allow the Bermuda high to build in. Expect highs of around 94 through the week. I would post what the models say for this week, but they all look the same.

By Friday, a trough will move into the Upper Midwest and drag a cold front with it. Let’s check out what the models have to say:


The 12z GFS 500 mb chart valid at 1 pm Saturday, and it’s pretty easy to tell where the action is – right over the Midwest. One would expect a line of showers and thunderstorms to trail from Michigan to Oklahoma.


And that is exactly what we see. This squall line should make it into the Mid-South sometime on Sunday. Timing will need to be resolved by later model runs. For now, Sunday appears to be the best chance for rain.

Now for the GFS crystal ball:


And again, the GFS goes back to a wet solution for July 4 morning. Again, take this with lots of salt. Tomorrow’s run may be completely different.

That’s all for today. Another update tomorrow.

Monday Afternoon Map Discussion

Welcome back to the Mid-South Weather Blog. I apologize for the lack of posting yesterday, but when the weather is this nice, you have to take advantage of it. Today has been a bit on the cloudy side with some peaks of sunshine breaking through as a disturbance riding the jet stream moves through the area. Any rain was mostly limited to the northern parts of Arkansas and the areas along the Tennessee River. Still, with enough surface heating and old outflow boundaries meandering around, isolated thunderstorms will still be possible. Where are we going from here? Let's check out the models.

12z run of the GFS valid at 7 p.m. Tuesday evening:

The first thing to notice is the trough in the east lifting to the north and breaking down with a general westerly flow across the northern half of the country. A ridge of high pressure builds into the area (which is shoving those westerlies north). With this ridge in place, we can expect warmer weather with highs in the low to mid 90s through the week.

Here's a look at the surface map for this same time frame:

That ridge of high pressure is evident at the surface as well by the southerly winds bringing in moisture off the Gulf. While it may look like some rain is possible, it will be the isolated pop-up shower or storm - a staple of summer in the Mid-South. Expect this to continue through Friday.

Now let's take a look at the GFS 12z valid 7 p.m. Friday night:

Change may be on the horizon as the ridge begins to break down, and a trough and associated cold front begin to drop through the Midwest. This is the best chance at widespread rain for the area as the front moves southeast. This is four to five days out, so timing will certainly will be an issue, but it looks the weekend could be wet some of the time.

Now for a quick peek into the GFS crystal ball for Friday morning, July 4:

A big trough anchored over the eastern half of the U.S. with the Mid-South at the base of it? That could mean a very wet holiday weekend.

Until then, enjoy the week!

Mid-day Q & A

First comment and question on the blog received today from David S:

could this be around the time where the flooding up north gets to us? i know it all crystal balls...but could we have super heavy rain...and an incredibly high crest? does the pyramid float?

I think a lot of people downstream along the Mississippi River will be wondering the same thing. We saw the combination of a wet spring and snow melt this year help the Mississippi River climb above flood stage in the Mid-South. This time around I'm not so sure. The National Weather Service recently put out a statement on their website addressing this question. The short version is that the river will remain below flood stage here in Memphis as the water moves downstream, with only the northern counties in TN experience any real effects. Could additional rain up north raise the levels higher? Absolutely. But I would guess that we would need a lot of rain here to get the Pyramid floating.

Interestingly enough, the GFS crystal ball continues to show something happening over the area around the 4th of July weekend:

This is actually for Sunday 1 p.m. on the 6th courtesy the 6z run. That's still a large thunderstorm complex over Arkansas.


Saturday the 5th could also be a very wet day across the Mid-South. I'll need to check out later runs to see if this same activity appears again. (Note: The 6z and 18z GFS model runs are usually not as reliable as the 0z and 12z.)

So to answer the question in as few words as possible, I think the river will probably stay below flood stage in Memphis, barring some terrible disaster to the north (a lot more rain) or here (tropical system stalling out over the Mid-South).

For more information on the computer models, you can go here. I'll try to find some more useful links and get them up on the right side of the page. There will probably be another update this evening.

Early Saturday Morning Edition

The storms approaching Shelby County last night really fizzled as the 10:00 hour came. Loss of daytime heating can do that. The official rainfall total from Memphis International was 0.17" of rain. Still the rain is a good thing. Even though we are well ahead for the year thanks to a wet March-May, it has been dry of late. Alright, where are we going from here? Let's dive in to the model runs:


This is the 6z GFS 500mb and vorticity map valid for 7:00 this evening. The heat is still on over the Southwest, as the ridge has built well into Canada at this time. The trough moving into British Columbia will help to flatten out the ridge into next week. The trough across the northeast appears to weakened somewhat. The northwest flow aloft continues. Coupled with a front sagging into the Southeast and humidity levels typical for summer, expect scattered showers and thunderstorms to be the weather story from Jackson (MS) to Birmingham to Atlanta.


And sure enough, there's the area of rain for today. Some good rain could fall over the Carolinas (a blessing at this point). Our temperatures will reach 84-86 today. It could be cooler depending on cloud cover, but mid 80s with a northerly breeze will make for a pleasant June day. Sunday will be more of the same, maybe a few degrees warmer, but nothing too oppressively hot.



Monday morning will feature more of the same for the Southeast. We might see a few showers in the morning, but other than that it looks dry to start the work week.

That's all for now. Updates later today, and more peeks into the GFS crystal ball, where snowstorms in the winter are the rule rather than the exception.

Friday Night Storms

It may be a rough hour to hour and a half for Shelby County as these two storms move through the county. Besides these storms, the rest of the area will remain quiet. Keep an eye out for these storms. I'm sure you can hear the thunder for those in Shelby County.

Friday Afternoon Radar

Courtesy wunderground.com, here is a look at the radar out of Memphis:

Not much activity in and around the immediate metro area, but showers and thunderstorms are to our north and south. Expect more areas of development as the front works its way through the area, but storms should remain below severe limits.

How does Saturday look? Here's the 12z GFS model run depicting the weather for 1 p.m. Saturday:


This model run is trying to keep a fairly broad area of showers and thundershowers across West Tennessee. Based on the activity today, I do not see a widespread area of rain. Scattered rains will be the rule rather than exception. The ridge continues over the Southwest, and the trough in the Northeast. The passage of the cold front overnight into the morning will mainly result in slightly drier air. The Tennessee Valley and points east hope to receive a much-needed 0.75" to 1" of rain as the model indicates.

Peeking into the GFS crystal ball for a future forecast, here is the map of Friday morning, July 4:


If you believe this model, we're in store for the mother of all Fourth of July fireworks display with a massive thunderstorm complex about to blast into the area dumping 3-4" of rain. Take this with an entire shaker of salt. The crystal ball often is very foggy.

Thursday Evening Map Discussion

Partly to mostly sunny skies dominate the weather across the Mid-South today with slightly warmer temperatures as the southerly flow returns to the area. As of 4 p.m. Memphis International Airport reported 86 degrees, which happens to be our high for the day, too. We'll be heading toward a low of 67 degrees tonight with partly cloudy skies. Now let's take a look at tomorrow...






Here is a look at the 18z NAM model run showing the weather for 1 p.m. Friday afternoon. You can clearly see the blob of precipitation across central Missouri. Also notice over northern Louisiana another batch of precipitation. Two systems will bring us chances for rain. A shortwave/piece of energy riding the NW flow aloft will move into the area enhancing lift and increasing rain chances. At the same time, a warm front will begin lifting north toward the Mid-South. The increase in moisture and approaching shortwave will kick off showers and thunderstorms. Fortunately, it appears the risk of severe weather will not be great. SPC only has us in the general thunderstorm area, but there will be some stronger storms possible.











Let's take a look at 1 p.m. Saturday courtesy the 18z GFS model run.





The majority of the rainfall should begin clearing out of West Tennessee and NE Arkansas as the cold front slides through the area. Northerly winds will keep the temperatures in the mid 80s for most locations. Much needed rainfall looks probable for the Carolinas, where the drought still continues. Iowa and the flooded Midwest continues to see dry weather, but with rivers still cresting, the catastrophic flooding continues.

I'll have an update Friday afternoon on the weekend and a look into future with the GFS crystal ball.

Thursday Forecast

Here is a look at the 18z GFS run (computer model) depicting the weather for 1:00 pm Thursday.







The hottest temperatures will remain firmly entrenched across the Southwest and Mexico. Much of the Southeast continues with the northwest flow aloft, and with the passage of a weak cold front earlier in the week, we have a northerly flow at the surface. Those will slowly shift to the south tonight as the front falls apart. As you can see, tomorrow will be dry across the Mid-South. Tropical moisture is being pulled northward into Florida. Some much-needed rain will fall there. Elsewhere, clusters of showers and thunderstorms will develop and ride south/southeast along that northwest flow aloft from Wyoming into Texas.

Here for the Mid-South, we'll continue with typical June highs in the mid to uppers 80s for Thursday. We'll wake up to 65-68 degrees in the morning. All in all, it will be another pleasant, slightly less humid day across the area.

Later posts will focus on rain chances for the weekend.

Welcome

Welcome to the Mid-South weather blog - a place to check in on what's happening in the world of weather in the Mid-South area. I'm not exactly sure where this blog will wind up going, but I hope you'll check in with us from time to time. The weather is always interesting, so this blog will always be, too.