Sunday, September 17, 2017

Summer's last gasp... how long does it last?

I think we all got used to below normal temperatures from late July through August and into early September! In fact, according to our climate summary, August was the coolest in 13 years! However, summer decided to make one last stand once the remnants of Irma moved out earlier this week.


While temperatures the past few days are not that much above mid-September averages, the humidity factor has caught some folks off guard with the Muggy Meter registering dewpoint values not far off mid-summer norms.


While heat indices in the mid 90s wouldn't be considered awful in the dog days of summer, by mid-September, I think we're all pretty much over it...

Looking ahead, this warm pattern continues throughout the upcoming week, with only slight abatement in the high temperatures as we head towards next weekend. Rain chances increase a bit by mid-week due to a weakness in the upper level high pressure that is currently controlling our area, but no cold fronts are expected that would bring lasting relief from the heat.


Overall, it appears we may be stuck in a warmer than normal overall pattern (though not necessarily as warm as the next several days) right through the end of the month. The long-range upper level pattern favored by climate models indicate a return to cooler than average weather by around the first of October.

As the sticky-ness lingers and temperatures remain very warm, know that the end is in sight as autumn officially begins this Friday at 3:02pm! Pleasant fall days are not too far away, especially since we've gotten a sneak preview recently!

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

August 2017 Climate Data for Memphis, TN

August Climate Recap

July temperatures were slightly above normal, but August returned to cooler than average weather for the third out of the previous four months. By the end of the month, only six of the previous 35 days had recorded an average temperature above normal, resulting in the coolest August in 13 years! I didn't hear any Mid-Southerners complaining about below average temperatures during the dog days of summer.

After running below normal for most of 2017, precipitation spiked above normal thanks mostly to the remnants of former Major Hurricane Harvey moving over the Mid-South on the 31st. Precipitation officially totaled 4.04" that day, which was the second wettest August day on record and also well over an inch more than Memphis typically averages for the entire month. Combined with previous heavy rain events that included three other days with more than an inch of rain, the month ended with over 9" of rain, the fourth wettest August on record. The remnants of Harvey resulted in areas of flash flooding, as well as many strong wind reports (including a severe wind gust of 60 mph at Memphis International Airport) and over 40,000 MLGW customers without power. Tornado Warnings were also issued mainly across the eastern metro as brief rotating cells resulted from Harvey. Tornadoes actually touched down well east of the metro (see map below). Additional scattered severe storms occurred on the 11th with a few reports of strong wind.

Severe weather reports across the region on August 31, associated with the remnants of Harvey. Thunderstorms in outer bands of the system resulted in tornadoes in northeast MS, northwest AL, and middle TN. Flash flooding reports were common closer to Memphis, as well as a handful of severe wind reports. (Graphic courtesy: Iowa State University).

Memphis International Airport, Memphis, TN


Temperature
Average temperature: 79.4 degrees (2.6 degrees below average)
Average high temperature: 87.5 degrees (3.8 degrees below average)
Average low temperature: 71.3 degrees (1.4 degrees below average)
Warmest temperature: 95 degrees (20th, 21st)
Coolest temperature: 65 degrees (24th)
Heating Degrees Days: 0 (0 above average)
Cooling Degree Days: 455 (72 below average)
Records set or tied: None
Comments: Eight days recorded temperatures at or above 90 degrees, which is xxx less than an average July. Year to date, the average temperature of xx.x° remains the second warmest on record behind 2012.

Precipitation
Monthly total: 9.29" (6.41" above average)
Days with measurable precipitation: 13 (6.2 days above average)
Wettest 24-hour period: 4.04" (31st)
Snowfall: None
Records set or tied: Remnants of Major Hurricane Harvey resulted in a daily record rainfall total of 4.04" on August 31st. That day was also the second wettest August day on record.
Comments: Year to date, precipitation has totaled 36.66" or 104% of normal, the first time year-to-date precipitation has been above normal since early February.

Miscellaneous
Peak wind: North-northeast/60 mph (31st) (effects of Tropical Depression Harvey)
Average wind: 6.9 mph
Average relative humidity: 74%
Average sky cover: 60%

Click here for a daily statistical recap for Memphis International Airport.

Cirrus Weather Solutions / MemphisWeather.net, Bartlett, TN


Temperature
Average temperature: 77.1 degrees
Average high temperature: 87.7 degrees
Average low temperature: 68.4 degrees
Warmest temperature: 95.2 degrees (20th)
Coolest temperature: 58.2 degrees (24th)
Comments: None

Precipitation
Monthly total: 7.13" (automated rain gauge), 7.79" (manual CoCoRaHS rain gauge)
Days with measurable precipitation: 9
Wettest date: 4.19" (31st) (via automated gauge)
Snowfall: None
Comments: No measurable rain fell from the 18th-30th, a span of nearly two weeks.

Miscellaneous
Peak wind: North/30 mph (31st)
Average relative humidity: 83%
Average barometric pressure: 29.99 in. Hg
Comments: None

Click here for a daily statistical recap for Bartlett, TN.

MWN Forecast Accuracy

MWN average temperature error: 1.48 degrees
MWN forecast temperatures within 2 degrees of actual: 82%
MWN average dewpoint error: 2.04 degrees
MWN forecast dewpoints within 2 degrees of actual: 70%

MWN's forecasts extend out five periods (2.5 days, or roughly 60 hours). Historical accuracy statistics can be found here.

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Sunday, September 10, 2017

More tropical remnants will pay a visit to the Mid-South

Following a frontal system that moved through Tuesday, the week has been phenomenal with well below average temperatures, sunny skies, and low humidity. Since July 27, we have had only 6 days with a daily average temperature above normal, so the summer has definitely ended in a cool way! I'm glad to have fall weather in the Mid-South - probably my favorite season!

Looking ahead to this week, it appears that the second consecutive major U.S. hurricane to make landfall, Harvey then Irma, will have remnants that affect the Mid-South. While Monday looks decent with still a good deal of sunshine and temperatures that peak in the upper 70s, the wind will be a more breezy at 10-20 mph with gusts as high as 30 mph.

As the remnants of Irma move into eastern Alabama on Monday night as a tropical storm, clouds and rain chances increase in the Mid-South, as does the wind. Rain becomes likely after midnight Monday night and continues Tuesday. The strongest wind will likely occur early Tuesday as we feel sustained north wind of up to 20 mph and gusts of 30 mph as Irma runs into high pressure to our north, increasing the pressure gradient and resulting in gusty wind. During the day, as the remnants move closer in tropical depression form, wind could actually lessen a bit as the storm itself weakens further and the center draws closer and the influence of the high to our north weakens a bit. As the ultimate track, and decay rate, of Irma becomes a little more clear Monday, the forecast may need adjusting a bit. It's possible that we could see a bit stronger wind, but overall I do not expect the rain rates or the wind produced by Harvey a couple weeks earlier. Tuesday's temperatures are likely to remain in the 60s, so it'll be a cool, wet, breezy day.

The latest forecast track from the National Hurricane Center for Irma.

Wednesday will see Irma's remnants dying out, but lingering showers in the area and less wind. It will also be another fairly cool day as temperatures likely only make it to about 70 degrees with cloud cover lingering. Rainfall totals in the Memphis area currently look to be in the 1.5-3" range (starting before sunrise Tuesday through the Wednesday showers).

Forecast rainfall amounts as of early Sunday afternoon from Irma's remnants. 2-3" of rain could fall between early Tuesday and Wednesday afternoon in the Mid-South.

Conditions improve heading towards the weekend as what's left of Irma's remnant low move east of the area, some sunshine returns and temperatures rebound back to 80+. Slight rain chances Thursday and Friday can't be ruled out. It appears that decent weather will occur for Friday night football, Cooper Young Fest, and Live at the Garden's closing concert, as well as Saturday's Memphis-UCLA football game - finally one not affected by a tropical cyclone!

We'll post the latest on Hurricane Irma and the effects on the southeast U.S. and Memphis area on our social media feeds. Also stay up to date with local conditions and forecast information via the MWN mobile app, available in your app store. All links are below.

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Monday, September 4, 2017

Our first autumn cold front nears, plus a look at Irma's potential track

Have you grown tired of the off and on summertime heat across the Mid-South? Are you ready for the fall-like weather to return to the Memphis area for September? If so, then we have some great news. Mother Nature is listening to your complaints. Fall will be back for the area this week.

The Trough of Change

As many head out to celebrate the Labor Day holiday, the weather is setting up for a big change in the next 48 hours. An upper level trough digging in from the Rocky Mountains will bring in rain and cooler air, beginning with a chance of a few showers on Monday afternoon. Those showers become more numerous heading into Tuesday, as the cold front associated with this trough pushes closer to Memphis. Highs on Labor Day will hit the upper 80s, with lows on Monday night dropping to the low 70s.

The trough moving in from the Rocky Mountains will help shove the cold front south into the Memphis area, bringing rain and cooler temperatures with it. (NOAA/NWS)
Tuesday marks the beginning of the cooler temperatures, with plenty of clouds and rain and a few thunderstorms likely. Definitely have your rain jacket and umbrella ready when heading to work or back to school, with highs only reaching the upper 70s. This comes as the cold front bringing all the rain pushes through the region early on Tuesday. Showers will begin to decrease Tuesday evening as the front digs deeper into Mississippi, with lows Wednesday morning in the upper 50s (yes, you read that right).

Throwing It Back to the 70s

It may feel like it's been a while since we've talked about highs only hitting the 70s in the Mid-South, but September feels like the right time for some summertime relief! Once the cold front pushes out of our area on Tuesday night and the upper level trough moves over the area, conditions will clear out with cooler temperatures too. Wednesday begins the new cool trend, with mostly sunny skies and highs only reaching the mid 70s. Lows will drop down to the mid 50s.

Friday's high temperatures will be in the mid 70s across the Mid-South, closer to our lows this past week than our recent highs.
The cooler trend continues into the late week, as Thursday and Friday continue with sunny skies and highs in the mid 70s. Lows once again drop into the 50s, something we haven't seen in several months! Temperatures will begin to warm a bit by the weekend as the upper trough lifts out, however highs will still be comfortable on Saturday (in the upper 70s) and Sunday (near 80). Sunny skies will continue too.

Could fall finally be here? Or will summer crank back up one last time in September? Keep checking our MWN human-powered forecast for the latest weather around the Memphis area, which you can also find on our MWN Weather App. Be sure to also follow us on Facebook and Twitter for all the great weather updates and fun facts.



Alex Herbst, Meteorologist
MWN Social Media Intern

Checking in on Irma

After one major U.S. landfall with Harvey ended the 12-year drought of U.S. major landfalls, it is becoming increasingly possible that we could have two of these in a month. Hurricane Irma is a category 3 major storm as it approaches the Caribbean Islands. Over the course of the next few days, it will take on a west-northwest track, likely moving it just north of the main island chain in the Caribbean, including Puerto Rico and Hispaniola. All of the islands in that chain could see tropical storm to hurricane conditions as Irma actually strengthens more.

The latest official track for Hurricane Irma. The MWN Tropical Page has the latest details.



The end of the week into the weekend is the tricky part of the forecast, though we’re getting within range of making some predictions that could be considered educated and distinctly possible, rather than just guesses or “hype-casts.” Irma is expected to remain a major (category 3+) hurricane until it makes landfall. Where that landfall happens is still TBD.

At the risk of getting “weather nerdy” on you, there is a major trough (that Alex talked about above) that will move into the northeast U.S. and have a direct influence on the track of Irma. At some point, Irma is likely to make a right (northward) turn towards that trough. Earlier it appeared that that might occur before it reached the Florida peninsula, pulling Irma north along the east coast. It now appears that the trough could lift north before Irma is able to start turning towards it, resulting in a later turn and a northward motion that could take it directly into south Florida. If it turns even later, it could go up the west side of Florida in the Gulf.

Multiple computer models provide a fairly consistent track for Irma until it nears Florida. However.... (see below)

...the American GFS computer model's ensemble system (basically, the model being run multiple times with different initial and forecast parameters) shows the true picture. There are potentially many options yet for Irma including landfalls from the Carolinas to the Florida panhandle. The European model (not shown) still also shows the potential for a narrow miss of the east coast with an earlier turn north. (WxBell)

We don’t know yet when that will happen, but NOAA and the NWS are starting a massive atmospheric data gathering surge to try and sample the upper levels as best as possible to help the forecasters, and computer models, more accurately predict Irma’s motion. If you have friends or family in Florida or along the southeast U.S. coast up to the Carolinas, they need to start preparing now for the possibility of a strong storm this weekend as forecasters work to more accurately predict the eventual track.


You’ll find much more information on the tropics on the MWN Tropical Page.

Erik Proseus, Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Wednesday, August 30, 2017

What to expect from Harvey in the Mid-South on Thursday

The remnants of former Hurricane Harvey will move right over the Mid-South on Thursday and Thursday night. This 7-minute video will describe the impacts expected. Slides used are included below for those unable to view the video.








Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Tuesday, August 29, 2017

Harvey pays a visit to the Mid-South

After watching Harvey decimate a large portion of southeast TX, the storm has finally started shifting northeast. In its sights... the Mid-South. Fortunately nothing like what occurred in Houston and surrounding areas will occur here, but we'll definitely feel the effects. Let's get into it.


A Flash Flood Watch will go into effect Wednesday afternoon and continue into Friday. The initial feed band of showers and a few thunderstorms will arrive Wednesday morning, though it won't be the main event. However, as with any rain originating from a tropical system, downpours are likely. By afternoon, we'll be in a pattern favoring scattered showers and thunderstorms, though it won't be a washout.

Rain chances will go up dramatically Wednesday night, especially as we approach Thursday morning. Heavy rain chances go up and the wind will start to pick up a bit, increasing to about 15 mph from the east. Thursday is "Washout Day" as the heaviest of the rain on the north side of the storm moves over the region. A couple of inches of rain are likely Thursday with very heavy rainfall rates in convective bands that sweep through. Wind will increase during the day and become gusty to 25-30 mph. Flash flooding becomes more likely in areas prone to ponding and flooding, especially in the concrete jungle.

The American GFS model shows precipitation moving into the Mid-South Wednesday with heavy rain Wednesday night into Thursday evening. This model, along with several others, predict dry conditions on Friday. (WxBell)

By Thursday night, as the Memphis Tigers open their season at the Liberty Bowl against Louisiana-Monroe at 8pm, rain will still be falling but models are starting to indicate that the rain may be tapering as the evening goes on, as low pressure from Harvey moves near or just east of the metro. As the vast majority of the heavy rain will be north and west of the low, once the low passes by to our north, rain chances drop quickly. So besides rooting for the Tigers, we need to root for a faster motion of the low! Wind will shift to the north but remain gusty to 30+ mph Thursday evening. The other potentially good news is that the primary threat from isolated spin-up tornadoes is east of the low, therefore that threat appears to be minimized in the metro.

The National Hurricane Center estimated rainfall from Harvey through Friday evening. A heavy band of 6"+ is forecast to set up from the metro northeast into western KY. (NHC)

The GFS model's predicted total rainfall through Friday evening shows the same band of heavier rain as NHC with 3-5" across the metro. (WxBell)

As far as preparation, plan ahead for significant rainfall Wednesday night through Thursday night with the potential for flash flooding and urban flooding. Make sure storm drains are cleared tomorrow around your home. Also you will want to secure lightweight objects outdoors that could blow around in 30-35 mph wind.

Looking ahead, with the faster motion of Harvey, we look to be drying out heading into the holiday weekend! In fact, Friday could end up being dry but breezy with comfortable temperatures. The Labor Day weekend looks great weather-wise with highs in the 80s and dry conditions. The next chance of rain arrives Tuesday with another frontal system reinforcing the below average temperatures we've experienced for most of August.

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Friday, August 25, 2017

Is summer over? And will Harvey visit the Mid-South?

While the summer was not overly hot, it seems a lot of folks are still ready to put it to bed earlier than it's ready to go. Kind of like a middle schooler and her parents. (I know, trust me...)

Yet here we are with a week left in August, knowing that we've historically had some hot Septembers, basking in early fall weather featuring low humidity, not-too-hot highs in the mid 80s, and very comfortable mornings in the 60s. Of course, that begs the questions - "Is summer over?" "Have we seen our last 90° day?"

Well, our forecast has no 90°+ highs through the end of August. And the week 2 outlook from NOAA for the first week in September (below) gives us a high chance of below normal temperatures. Indeed, even the long-range model outlooks show a decent chance of below, or perhaps near, average temperatures into the middle of September.

The 8-14 day temperature outlook from NOAA shows a good chance (nearly 50%) that we will experience below average temperatures for the first week of September. (NOAA)

By the time we get to mid-September, average temperatures are about where they are right now - in the mid 80s in the afternoon and mid 60s in the morning. In other words, the "expected" trend here is for roughly this temperature patter to continue for the foreseeable future. Does that mean we won't reach 90° again? No. But as we get towards early fall, the likelihood of dewpoints that cause a 90° day to feel like 100° is also not that high.

In other words, even if we get a "warm" day that sees a high temperature that starts with 9, it probably will be just that - a pretty warm day, but not a sweltering one.  A couple of facts: record high temperatures at or above 90° have occurred into mid-October, and the average last 90° day is September 19. We aren't there yet!

What about Harvey?

Nationally, all weather eyes are trained on the Texas coast as Hurricane Harvey. With wind speeds bumping category 3 strength and minimum pressure, expected storm surge, and forecast rainfall on a category 4-5 level, it's worth your attention.

Exploding from a Tropical Depression Wednesday night to a category 2 storm last night, Harvey is ready to make its presence known over southern and eastern Texas and at least the west half of Louisiana. Projected rainfall amounts are ark-worthy, which I find particularly disturbing for Texas, where sometimes everything does seem bigger. I fear the images we see from the Lone Star State this weekend, and continuing into early next week, will be unconscionable. The battering that the coastline and near-shore areas take from 100+ mph wind and storm surge that is higher than any person alive is tall could somehow be overshadowed by the two to three FEET of rain that falls across parts of the region.

Forecast rainfall over the next week from Harvey. Houston metro is included in the 20"+ area, resulting in a total of over 5 million people forecast to receive 20" of rain. (NHC)

As hard as it is to predict, lives will unfortunately be lost. And in case you wonder, meteorologists can gawk at the data all day, but those with a heart don't root for the weather, we root for the people and we think about them when using words like these to describe likely impacts:


I'll leave the reporting and forecasting for those areas to our south to other experts in those areas. However, this will be a long-lived, high-impact system. It will take days to move out of the central Gulf Coast region, which makes the forecast for Memphis and surrounding areas that much more difficult. For more information, visit the MWN Tropical Page.

The forecast track of Harvey valid at 1pm Friday. Notice after landfall that it barely moves through early next week. (NHC)
That said, the most reliable medium-range forecast models that we employ do, in fact, move the remnants to the northeast. We will see high clouds over the area this weekend, but dry conditions continuing with moderately low humidity and highs in the 85-88° range. By early next week, a front will drop into the area, but with limited moisture to work with, rain chances will be spotty. Scattered showers and perhaps a few thunderstorms are possible early in the week. By mid-week, things become a bit more uncertain depending on the ultimate track of Harvey's remnants. For now, I'm including elevated rain chances for the mid/late week period. There is a potential for very heavy rain if the remnants move close by. Too soon to tell...



Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Monday, August 21, 2017

Meteorologist perspectives on #Eclipse2017, and what happened "out east"

Some may call it overrated.

Others a let down.

Others still, a case of bad luck.

A rain cloud in the wrong place at the wrong time.

For many of us that saw it though, it was awe-inspiring and beautiful, even if the partial eclipse was, well, partially eclipsed...

And if you didn't see the actual eclipse, maybe you saw something that you might've overlooked on "just another day." Like this for example...

Iridescence in the clouds as the sun was eclipsed, despite not seeing the eclipse itself. Photo credit: @memphisjq
With a vantage point on the roof of a roughly 50-foot tall building in south Memphis, I was able to avoid the early storms that built over southeast Shelby County, in turn harassing potential viewers in northeast and central Shelby County. While the cumulus field occasionally obscured the view, it also produced pictures like that shown below, which I was able to take, and view, with the naked eye, thanks to the filter provided by the clouds.


Occasionally a clear view provided for a phenomenal perspective of a celestial confluence that won't occur again for nearly 7 years (a brief lull compared to the recent history of such occurrences).

I didn't have professional photographic equipment, and wouldn't have known how to operate it if I did, but I was creative enough to put the eclipse glass against the lens of my fairly-advanced smartphone camera, point it at the subject matter, zoom in, then quickly tap the eclipsed sun to focus and just as quickly tap the shutter button for a quick pic. I got one "decent" shot, shown below.


While my own photographic evidence doesn't nearly stand up to the stunning imagery I have seen shared on social media (some of which I have shared with you on my Facebook and Twitter feeds), it will help me memorialize the event and reinforce my own observations of the first coast-to-coast total eclipse in nearly a century.

What does a meteorologist say "awe" at during an event of this magnitude, without having personally witnessed totality, but something very close?

The progression of the moon across the sun's face over time.

The hard-to-miss dimming of the surroundings that could not be attributed simply to passing clouds.

The passing clouds that seemed to create another inspiring moment each time they parted.

Watching a brand new satellite system, GOES-16, capture the darkness that swept across the nation over a couple of hours, each image frame only 5 minutes apart.

And when light blossoms behind the passing shadow on said satellite loop, realizing that the cumulus clouds built previously by the heat of that same sun have been snuffed out and dissipated after being robbed of their heat source for less than an hour.

Also, images produced by NASA of a space-borne laboratory and living quarters for six brave souls, dwarfed by the object that provides life to this planet, as it it turn is blocked by a moon that is 1/400th its size.

And honestly, seeing all of the excitement and wonder you shared in your pictures and knowing that, for one day anyway, the "awe" was back in science for adults and children alike.
After seeing and hearing about the experience in "totality" however, I have decided to make it my mission to be in an even more awe-inspiring position on April 8, 2024...




So what about the forecast? Why did those in eastern Shelby County get "robbed?"

Well, I must say that our forecast going into the day (which had really not changed to any degree since late last week) was not that far off from a big picture perspective. Overall, conditions were partly cloudy as predicted. And the 20% rain chance that was also predicted materialized, to some folks detriment.

What I didn't catch onto this morning, but there were hints of in morning weather model data, was how quickly the muggy atmosphere would heat up. With a heat index of 103° at the airport by 10am, it was quickly becoming obvious that the combination of heat and atmospheric moisture would result in convective clouds (cumulus - those puffy ones) forming earlier than originally anticipated. I expected some cumulus, but I didn't expect the large build-ups that would produce rain as early as noon. Once those towering cumulus built, there were some who were going to end up with an obscured view of the sky. I had expected that to occur between 1-2pm, not by noon.

I have to give credit where it's due though, even though picking out one model from the bunch to be "the model of choice" is sometimes hard, especially when all the others disagree. The high-resolution North American Model (NAM) from overnight Sunday night was onto something. I even tweeted it early this morning.

However, even it was just a bit late. (How crazy is it that I even stated that it better not "occur an hour earlier." Perhaps a jinx?) The placement of that predicted cell in Shelby County within an hour of it occurring on a 12-hour forecast is an example of just how good these high-resolution models are getting. And sure enough, if I had completely bought into that particular model run, I could've told those in eastern Shelby County when you woke up this morning to find a place a few miles to your east or west for best viewing. But alas.... pinpointing cell placement and cloud cover in a very small region like a handful of counties is still harder than the southern snow forecast.

So, though I can't tell you how much rain you will get and when the next couple of days, I CAN tell you with a high level of confidence that you will find the weather much more PLEASANT beginning Thursday and continuing into the weekend. I for one and looking forward to 60s again in the mornings and low humidity 80s in the afternoons!

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Saturday, August 19, 2017

Eclipse forecast and viewing details, and an early taste of fall?

I've got some good news and some great news in the forecast... but first the forecast you're most interested in - the eclipse forecast, which is our good news!

So, are we gonna see the eclipse?

The short answer: yes!

An upper level ridge of high pressure will exercise its influence on the forecast through early next week, including Monday. What does that mean? Summer-like conditions. Heat and humidity this weekend will continue into Monday as heat indices peak in the 102-105° range each afternoon. I can't rule out a few stray thunderstorms, but not everyone will see rain. Most of these showers or thunderstorms don't really get started until 2pm or later.

So for Monday I expect partly cloudy skies (those white puffy clouds that only temporarily block the sun) and mainly dry conditions. It will be HOT with temperatures near 90° at 1:23pm Monday and a heat index above 100°. Plan accordingly.



I wrote a complete "Viewing Guide" to the eclipse that I encourage you to read if you haven't. Since then I've seen some misinformation about a few things related to eclipse viewing. My Facebook post from yesterday addresses those:



Viewing Safety

So to be clear, you only need to wear eclipse glasses when you are wanting to view the sun directly. You don't need them when you're outside on Monday for normal activities (though sunglasses will probably be in order like any other summer day!). And here in the Mid-South you should NOT look at the sun Monday (or any other day for that matter) without eclipse glasses! The only time that you can view an eclipse without eclipse glasses is during totality, and that won't happen here.

I understand that Pink Palace and American Paper Optics in Bartlett are the only places left that have NASA-approved glasses and are selling them this weekend. Prepare to pay $3-5 a pair for them and also prepare for long lines! If you can't get glasses, there are a couple of "old-school" ways to view the eclipse. My friend Ryan Vaughan of KAIT-TV in Jonesboro shows how to make a viewer out of a cereal box and meteorologist Brad Panovich explains how to use two pieces or cardboard or stiff paper to make an eclipse projector. Also, here's a really good video tip on taking pictures of the sun with a zoom lens and no filter!


Now the great news... 

A cold front will move through this coming Wednesday and it's a doozy! Unlike the fronts of the past couple weeks that provided some short-term relief but returned north and put us back in the soup, this one looks to have some staying power. Look for an increase in thunderstorm coverage a bit on Tuesday as the front gets closer, then a high chance of thunderstorms on Wednesday as it moves through. Once the front clears though, we'll see a significant drop in the humidity levels on Thursday and temperatures that also respond by falling into the mid 80s for highs, with lows that could get down to 60° outside the city by the end of the week and into next weekend.


In fact, the week 2 outlook from NOAA that I posted yesterday shows a good chance of below normal temperatures for the end of August and beginning of September! Could this be the end of 100° heat indices for this summer? I'm not quite ready to go there yet, as we can get some hot days in September, but I do think we'll be getting out first taste of early fall by the end of the week. In honor of the now-recovering Rick Flair, can I get a...


The most recent forecast details and additional cool eclipse tips will be posted on our social media feeds listed below, and you can always get the latest forecast info on our website, mobile web, and mobile app, also linked below.

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Sunday, August 13, 2017

Summer takes another break, but makes a comeback this week

It's been kind of a strange summer. Certainly not overly hot other than a brief stint in mid-late July. In fact, since July 28, we've now had 16 consecutive days of below average daily temperatures and that will be extended at least three more days as we head into mid-August!


You can thank a series of fronts over the past couple of weeks that have moved over and through the metro for the additional cloud cover, periods of acceptable humidity levels, and scattered rainfall. That trend will continue as we head into the work and school week. The closest front is to our south but it is very weak, so wind direction is variable to southeasterly. As your Sunday progresses, a mesoscale convective vortex (MCV), or remnant weak low pressure left behind by a previous thunderstorm complex, will move across the Mid-South from the west as upper level flow pushes it east-northeast. This will bring a good chance of rain to the area later this afternoon and into the nighttime hours.

Simulated radar from the HRRR model through the early morning hours on Monday shows a large slug of moisture moving across the metro later this afternoon and into the early nighttime hours. You'll notice the distinct "spin" in the area of potential thunderstorms on the back side of the rain area. That is the low pressure system driving the precip, what we call a mesoscale convective vortex (MCV). (WxBell) 

A few thunderstorms are possible, mainly south of the city where a Marginal Risk (level 1/5) of severe weather exists. I do not expect to see any strong storms in the metro. Rainfall totals could rise to a half-inch to inch in some spots by Monday morning.

A low-end severe weather risk exists for the far southern portions of the metro today. I expect no severe weather for most of the metro and only a low chance of thunder north of the MS/TN state line.

The week ahead

In the wake of the rain today and tonight, Monday looks to be drier though a chance of storms is in the offing, mainly south of the city. Though humidity will be back in the "muggy" category, temperatures remain mild with highs in the mid 80s due to only partly sunny skies.

Additional scattered showers and thunderstorms will be possible nearly each day throughout the week and into next weekend, although not everyone will see rain every day. In fact, rain chances diminish some mid-week as upper level high pressure begins to build to our south and push north a bit. That will squash rain chances a bit, leaving a few possible in the heat of the day.

Speaking of heat, it's making a comeback under this high as well. We'll be back above 90° by Wednesday with dewpoints getting closer to the "miserable" range as they near 75°. That'll mean heat indices back above 100° and overnight lows that get no lower than the mid 70s. The mugginess could subside a bit by next weekend as the pattern shifts just a bit, but typical summer weather will continue right into the weekend.

Forecast temperatures for the next 10 days from the National Weather Service "National Blend of Models" (NBM), which averages today multiple models to depict the best possible forecast using them all. (WxBell)

Eclipse Forecast

I know everyone's keen interest is on the eclipse forecast a week from tomorrow, August 21. Eight days out can still be a crap shoot as far as cloud forecasts, but the overall pattern doesn't necessarily bode well. Of course, a couple hours of partly cloudy skies is all we need, but it doesn't appear Eclipse Day will be a bright sunny day dominated by high pressure at all levels. Stay tuned and cross those fingers!! Starting tomorrow, eclipse day will be in the extended range forecast on your MWN app!

For more on viewing the eclipse in the Memphis area, see our Viewing Guide if you haven't already!


Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook, Twitter, and Google+
Visit MemphisWeather.net on the web or m.memphisweather.net on your mobile phone.
Download our iPhone or Android apps, featuring StormWatch+ severe weather alerts!
MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder