Much-needed rain closes out a hot two-month start to summer 2022

Today closes out what will go into the record books as the hottest June/July on record in Memphis, ironically with one of the coolest days in the two-month record! Until this past Friday, not a single day since June 11 had failed to reach 90 degrees, and most of them were in the mid 90s or higher. Sixteen days have seen the high reach 100 degrees! Not only will the average temperature (average of all highs and lows) be the hottest on record, so will the average high temperatures, eclipsing 95 degrees for only the third time on record (including 1952 and 1954). 

That heat has been exacerbated by, and with some likely contribution from, the lack of precipitation. Until a wetter pattern started on Friday, total precipitation for the past two months has been more than five inches below the norm of around nine inches. This has resulted in flash drought conditions as shown below. The drought allows the temperatures to be even hotter because there is less moisture fed back into the low atmosphere from the ground, allowing it to heat more than usual. 

A comparison of the drought index from June 14, when summer was starting pretty decent, to this past week, when we were all crying "mercy" following a brutal six weeks of heat. This weekend's rain should help things improve on the drought side when this week's index is released. (U.S. Drought Monitor)

But this weekend has provided a reprieve, as a front finally stalled over the area and moisture from the southwest streamed in, allowing multiple rounds of precipitation to fall over the entire region. While the ground eagerly soaks up the welcome rainfall, the clouds and precip are holding high temperatures below normal on consecutive days for the first time in a month. Muggy conditions, featuring dewpoints in the mid 70s, are keeping morning lows warm, but anything below 80 degrees is likely ruled a win right now!

Looking ahead, the upper level trough that resulted in this welcome pattern shifts to the east to start the week. We'll likely see elevated rain chances into Monday afternoon before high pressure at the surface and upper levels builds back in for the next several days. This pattern will mean a return of more typical summertime conditions. In case you've forgotten what is "expected" in summer, it isn't 100 degrees and parched earth! We're looking at highs in the low to mid 90s, enough humidity to kick heat indices just above 100, lows in the mid 70s, and small thunderstorm chances during the afternoon hours that will probably miss more of you than they will rain on. But we can't rule them out! 

The Sunday morning European model ensemble average of mid-level height anomalies for the coming week. Basically, high pressure aloft centered over the Southwest U.S. will control most of the country this week with slightly above average pressure over the Mid-South contributing to summerlike weather conditions. (WeatherBell)

So while August will be hot, it should start off not-as-hot as we had for much of the month of July, which will be the second hottest July on record behind only the benchmark of 1980.

Erik Proseus
MWN Meteorologist

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Farewell spring, it's been fun...

It has been a wonderful spring so far across the Mid-South, and for many in the Southeast. April was a below average month for temperatures, and that trend has continued into May. In fact, we are 5-7 degrees below average so far for the month of May! With average high temperatures now rising into the 80s, this has given us several weeks of beautiful, pleasant spring weather overall. However, after today, rain chances and cloud cover will decrease, allowing temperatures to quickly rise through the 80s and approach 90 degrees by Saturday. Farewell spring!

This month-to-date (May) high temperature anomaly map for the U.S. shows much of the eastern two-thirds of the country has experienced well below average temperatures for the first half of May. (WeatherBell)

We knew it couldn’t last forever, and sure enough a major pattern shift is coming for us here in the Memphis area. The cool weather was caused by a persistent trough of low pressure over the Mid-South and eastern U.S., which helped to continually funnel cool air down into the south from the northern US and Canada over the last month and a half. The hot weather has been confined to western portions of the country, as a large ridge of high pressure with sinking, hot air has refused to budge for the month of April and into the first half of the month of May. Now, that pattern is finally changing. A trough will dig into the western US, bringing the West Coast and Rocky Mountain region some much needed rain, cooler air, and wildfire relief. 

Unfortunately for us, a large ridge of high pressure looks to build in over the next few days and intensify, ending our very nice spring weather and setting the stage for the arrival of more summer-like weather. With this high pressure center sitting to our south and east, the clockwise flow around the high will pump Gulf moisture directly into the Mid-South, quickly warming our temperatures. Due to the sinking air of the high pressure, rain chances will also diminish, leaving us with lots of hot sunshine and humidity. 

As we go into the latter part of this week, an upper level pattern known as an ‘omega block,’ because the pressure pattern resembles the Greek letter omega, will set up across the United States. This will keep the ridge of high pressure parked over the central and eastern US for at least the next week, if not longer. This is a classic pattern for hot temperatures under the high - a “heat dome” is not a bad way to describe it.

The upper air pattern setting up for this weekend and early next week features an 'omega block' across the country, with high pressure covering most of the eastern half of the nation. (European model, WeatherBell)

The ridge sitting over us for so long will allow temperatures to quickly climb each day, and our first 90 degree days of 2021 are in the forecast for this weekend. In fact, almost every day next week has the potential to reach the 90 degree mark. Luckily, many area pools are beginning to open for the season, and next week is looking like prime time to inaugurate the neighborhood pool for the summer. The center of the high pressure will be to our east, so we should escape the more extreme heat expected for areas like southern GA and northern FL. Some of those areas could approach 100° next week! 

These kind of patterns are notoriously hard to break, and we could be looking at a couple weeks of hot, dry weather. Dry as in lack of precipitation, not in lack of moisture, as there will be continuous southerly flow off the Gulf, keeping our dewpoints high and making for a pretty unpleasant feel outside. Feels-like temperatures will be several degrees higher than actual temps, so find a way to stay cool. Summer weather lovers, your time is coming! 

Another concern for this pattern is the persistent lack of precipitation. With temperatures well above normal and very little cloud cover, evaporation rates will be high, and the nearly 3 inch rainfall surplus for the year could quickly be erased. Models are showing very little in the way of precipitation for the couple weeks. Looking at the European model through next Thursday, only a quarter inch of rain is forecast to fall, with most of that coming today. The GFS model is a little more optimistic on rain chances returning late next week, but that could change as we get a closer in time - definitely something to watch, especially for those with interests in agriculture. 

The European model forecast precipitation from today through the next 10 days. (WeatherBell)

As the heat of summer approaches, it’s a good time to revisit some heat safety tips. Wear sunscreen, especially during the afternoon hours, as UV indexes will be maxed out across the area next week. Stay hydrated, especially if you are planning on being outside in the peak heating of the day, and take plenty of breaks.

If you are planning on working out outside, it would be best to do it in the morning or evening hours. Heat is not something to mess around with, it kills more people each year than hurricanes, floods, earthquakes and tornadoes combined! Stay cool and stay safe Memphis, and get ready - summer is well on the way! 

Christian Bridges

MWN Social Media Intern

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More hot weather... but a (relative) end is in sight!

Two weeks ago in this space, we asked the same question and didn't get an appropriate answer: "when will the heat finally end?" This time we ask with more desperation and urgency!

Never-ending summer brings record heat and drought

 Summer 2019, though it started a little late, seems to never want to end! Relative to normal, September has been particularly brutal, ranking warmest on record and top 3 driest through the 28th.

In addition to the heat, moderate drought conditions have developed rather quickly the past couple of weeks for parts of the metro, according to the U.S. Drought Monitor.

The U.S. Drought Monitor indicates a large portion of TN is now in "Moderate Drought" conditions, including much of the TN portion of the Memphis metro.

The lack of precipitation this month has brought the drought conditions, but also contributed to the record high temperatures due to dry ground, despite increasingly lower sun angles as we head into fall. Officially, just over 0.10" of precipitation has occurred this month, which ranks third driest on record, with no more projected until at least the end of the week.

As we head into the final days of the month and the calendar turns to Halloween month, record high remains in the forecast and 90s are growing supremely tiresome.

So, when does it end?

A few more days of heat

Unfortunately, we'll have to get through another few days of likely record-breaking heat as mid-summer high pressure bakes the parched southeast U.S. We will probably tie or break a couple of daily record highs, and the all-time October high temperature of 95° will get threatened Tuesday and Wednesday. In fact, I have high confidence that we'll set a new monthly record this week.

Normal and record maximum temperatures for the first week of November in Memphis. The all-time record high for October is 95°, which could be broken this week.

By Thursday, the high will start to lose its influence a bit as a strong trough (that has brought winter weather to the northern Rockies this weekend!) shifts east while weakening. That shifting trough should push a cold front into the Mid-South Thursday night or Friday, which should take the top layer off our heat cake as we head into next weekend. Look for temperatures to drop about 10 degrees by Friday into the weekend, with highs in the mid 80s or so. While still above normal (which by the end of the week will be around 80), it will be a welcome shift in the right direction. Rainfall will likely be limited with the front.

A pronounced ridge of high pressure at the mid levels (18,000 feet) dominates the eastern U.S., while a strong trough dominates the west to start the week. By week's end, the ridge flattens (weakens) as the trough pushes over the top of it, resulting in a reduction of the record heat in our area by week's end. Colors are based on the amount of anomaly present in the pressure pattern. (European model via WxBell)

As we head later into the weekend, or early the following week, models are hinting at reinforcements arriving. That could bring higher rain chances and additional likely put a cap on any additional "re-warming." I expect this week will be the last string of ninety degrees days we will see this year.

#TeamMWN staff changes

Over the past couple of weeks, we've had a series of changes in the "intern department" with #TeamMWN. Recall these Mississippi State University meteorology students are the ones that keep our social media channels updated and do occasional blogging and forecasting. I am eternally grateful for the work that the "retiring" interns have done and look forward to the new students showcasing their skills and talents over the coming months.

Those who have departed recently include Ethan Black, who is now a mathematics major at MSU, and Jennifer Lambers, who has just started her first broadcast meteorologist position at WALA FOX10 in Mobile, AL! Congratulations!

Our new interns include:

• Paige Davide - a first-year Meteorology graduate student
• Max Magness - a first-year Meteorology graduate student
• Alexa Santa - a sophomore majoring in Meteorology

Each will bring their own "flavor" to the social media feeds, while serving to keep all of you informed on the latest trends in Memphis and Mid-South weather. (I'm lowering the hammer though if they cannot collectively figure out how to push the summer heat out of here!) In addition, spring addition Caroline Sleeper remains on the team as our "senior-most" intern. She is a Junior in Meteorology at MSU. On their behalf, I say #HailState and Go Bulldogs!

Erik Proseus
MWN Meteorologist

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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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The Summer Swing Begins in Memphis This Week

Are you ready for the summer? Are you ready for the sunshine? We've got warmth and sunshine for much of our week ahead, but some storms could rain on our parade heading into later this week. Let's dig into the details.

A Sunny Start

Sunday has brought abundant sunshine throughout the afternoon for the Memphis area and temperatures running mostly in the mid-80s. Lower humidity helps too, and that pattern is likely to continue into the beginning of the work week. Temps will slide into the mid-60s on Sunday night with partly cloudy skies, before jumping back up to the mid-80s on Monday.

The next chance of showers and storms comes on Monday night as a "reinforcing" cool front pushes through, though any precipitation should be isolated in nature and mostly remain to our north. There will be a likely increase in clouds on Monday ahead of any rain, but overall should be a good day.

Tuesday will see any early clouds decreasing with continued low humidity and warm temperatures. Wednesday continues the pattern of warmth, albeit with slowly rising humidity. It could become a bit more sticky, but temperatures remain in the mid to upper 80s for highs the middle of the week. The sun will remain a prominent feature in the forecast those days, while overnight will see mostly clear skies and lows in the upper 60s to near 70. Be sure to keep yourself and your pets cool in the heat of the summer coming up.

Here are some smart tips on how to keep your pets safe and cool this summer.

Summer Storms Are Coming

As the latter part of the week approaches, there is an increasing chance of pop-up showers and thunderstorms around the metro area. With the heating of the day where temperatures could approach 90 degrees, along with increased humidity, it would not be surprising to see some storms fire up late in the afternoon and into the early evening hours.

Temperatures continue to remain warm through the rest of the week with highs in the upper 80s to near 90. Lows will be on the rise too, with most nights dropping into the lower 70s.

Heading into the weekend, we will be watching an approaching cold front from the west that could bring more widespread rain and thunderstorms just in time for the weekend. Fortunately, this messy weather should clear just ahead of the July 4th holiday coming up.

Be sure to follow along with us on social media for all the latest weather for the Mid-South. Follow @memphisweather1 on Twitter or like us on Facebook. You can also download the MWN app from the Apple or Google Play stores, featuring pinpoint severe weather alerts from StormWatch+.

And one last request - the Commercial Appeal's #MemphisMost contest ends Monday morning at 9am, and we've been nominated for "Most Accurate Forecast" for the first time ever! Please consider casting a vote at www.MemphisMost.com tonight or early Monday. You can even vote once an hour! Thanks much and have a great week!

It's not too late to vote for #MemphisMost 2017! Help us crown the Kings of Memphis at https://t.co/JW4UL2FmaN now until Monday at 9 am! pic.twitter.com/ewi1b2wee1

— Commercial Appeal (@memphisnews) June 22, 2017

Alex Herbst, Meteorologist
MWN Social Media Intern

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Summer 2016 will likely be remembered for unrelenting heat

The summer of 2016 (at least meteorological summer, which consists of June, July, and August) is halfway over, and though not record-breaking, it has certainly been consistently hot!

While Memphis hasn't officially reached 100° yet this summer, perhaps the most notable statistics are related to the unrelenting duration of the heat. We simply haven't caught a break yet this summer! Unfortunately, both the short-term and longer-term forecasts do not offer a lot of hope for those tired of the heat. First, a little more about the heat of the past month and a half...

Summer 2016 Heat Statistics

Last month was the seventh warmest June on record in Memphis as high temperatures averaged nearly four degrees above the long-term average of 88.9° and low temperatures were more than three degrees above the climate average of 70.3°. So far, through the 16th, July has had an average high of 93.2° (1.6° above normal) and an average low of 76.1° (2.3° above normal) for an average temperature for the month that is nearly two degrees above normal.

Speaking of unrelenting, since June 1, the coolest high temperature has been 87°. We are in the midst of a streak of 32 consecutive days with high temperatures at or above 89° that started June 15. In fact, if it weren't for a high of 89° on July 11, that streak would be for temperatures at or above 90°. One additional statistic that speaks to the persistence of the heat is this: since May 24, only four days have had daily average temperatures below normal, and each of those was only 1-2° below normal. Despite all that heat, only two records have been set or tied and both were for warmest daily low temperatures (80° on June 25 and 81° on June 17). I'll say it again, we simply haven't caught a break!

An analysis of the departure from normal temperatures for the past 45 days (since June 2) shows the widespread nature of the warmth across the U.S. with the only below normal temperatures in central TX, along the CA coastline into the Pacific Northwest, along the U.S./Canadian border into New England, and a small portion of the Mid-Atlantic. Graphic courtesy WeatherBell.

Short-Term Forecast

Looking ahead in the short-term, upper level high pressure strengthens across the southern U.S. over the next day or so, then expands northward towards Canada into the Midwest. That means no relief in sight this week from the heat, and in fact, high temperatures on a few days could get near the warmest days so far this year (98° on three days in late June).

The GFS model shows a massive ridge of high pressure at 500mb (or about 18,000') centered over the Plains on Wednesday morning, which is representative of conditions for much of the coming week. Departures from normal conditions are indicated by color shading, with oranges being above normal and blues below normal. The strength of the high pressure indicates suppression of precipitation as weather systems move around the periphery of the high. Graphic courtesy WeatherBell.

The animation below shows the NWS National Blend of Models high temperatures from today through next Saturday. It is easy to see the heat expand as strong high pressure aloft causes the heat at the surface to get more intense. (If the animation doesn't play, click here to view it in a separate window.)

A weak upper-air disturbance will move into the region on Tuesday, perhaps bringing a thunderstorm or two, mainly to west TN, but that should have little effect on the temperatures that day, other than brief cooling for those that receive rain. With high pressure at the surface centered to our east, low level wind will be from the south, and you know what that means - the Gulf of Mexico will be "open for business!"

As moisture streams into the region from the south, expect daily heat indices to be over 100° as highs reach the mid to upper 90s. Some days will see heat indices of 105-110°, necessitating Heat Advisories. Next weekend, a slight weakening of the ridge could mean very low rain chances re-appear. However, if you work outdoors, please take the heat seriously and find time for breaks and drink plenty of water this week. Click here for the detailed week-ahead forecast from MWN, or consult our website or mobile app (links below).

Longer-Term Outlook

As for the long-term, there's actually little hope for the rest of July as that ridge of high pressure will be the dominating force. The NOAA Climate Prediction Center outlook for the past week of July indicates a very strong chance that above normal temperatures continue. Long-range climate models also indicate a likelihood of heat remaining in place to some extent through at least mid-August. It could be interesting to see where the meteorological summer of 2016 ends up when compared to some of the hottest summers on record (as of now, only 1980, 2010, 2011, 2007, and 1954 have been warmer).

NOAA/CPC predicts with high likelihood (nearly 60%) that above normal temperatures will continue from July 24-30. In fact, there is a high likelihood that all of the nation will experience above normal temperatures during this period except the Pacific Northwest.

NOAA/CPC also predicts a better than 50/50 chance that above normal temperatures continue for the first 2 weeks of August across the southern U.S. and west of the Continental Divide.

Stay cool!

Erik Proseus
MWN Meteorologist

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Summertime weather sticks around into September

Though "meteorological summer" ended on August 31, Mother Nature isn't paying any attention to the calendar as summertime conditions continue well into September. We've started off the month with a couple of days in the 90s and, unfortunately, the long-range forecast includes many more as we head into the Labor Day weekend, also the opening weekend of the college football season.

The weather pattern is dominated by an upper level pattern more akin to mid-summer than early fall as a ridge high pressure aloft encompasses much of the eastern, central, and southern U.S. This ridge, as evidenced in the video loop below by the light red/mauve colors, looks to morph a bit over the next 10 days but generally it remains fairly well entrenched across a good part of the U.S. This will mean continued above normal temperatures for at least the next week with very low rain chances.

Video above shows a loop of the next 10 days of upper level [18,000'] heights as forecast by the Wednesday mid-day GFS model. Mauve/light red colors are high pressure, which sticks around for much of the next week or more.

As for the beginning of the Delta Fair this weekend, Labor Day celebrations, and the kickoff to the Memphis Tigers football season on Saturday evening, expect heat to build, resulting in high temperatures in the mid 90s during the afternoons (low 90s at kickoff at Liberty Bowl Memorial Stadium on Saturday) and low to mid 70s for early morning lows from now through early next week.

A couple of days ago I thought a cold front may push through early next week, but that scenario looks to be delayed by at least a few days, so 90°+ weather could last well into next week. Rain chances will be no better than the isolated thunderstorms that happened to form right over the city on Wednesday afternoon. Hang in there though - once this heat breaks, I expect it'll be downhill into autumn! We'll just have to wait a little longer than some of us might like! For the complete MWN Forecast, check out our mobile apps (links below) or click here for our mobile-formatted forecast page.

NOAA total rainfall estimates through Labor Day are very low - almost nothing.

Erik Proseus
MWN Meteorologist

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El Nino ramps up - what it means to Mid-South weather

Climatologists and environmental scientists expected El Nino to appear over the winter of 2014-'15 and, though it never officially did, it appears it was only tardy, not absent. As we head into summer, NOAA has now indicated that a weak but strengthening El Nino is present and could become one of the strongest in quite some time later this year. In fact, NOAA is forecasting a higher than 80% chance that El Nino will continue through the remainder of the calendar year.

Sea surface temperature anomalies (departure from normal - orange to red above normal) increased over the past 3 months in the El Nino region from the west coast of South America into the central Pacific indicating a strengthening El Nino.

The various long-range computer models almost all support a strengthening El Nino this year with some indicating it could become very strong. 

El Nino's effects on winter weather are fairly well documented and understood (though local variations certainly exist and no two El Nino patterns are the same) but the effects in summer tend to be more muted and less predictable. There have also been many fewer instances of a strong summertime El Nino in recent decades, thus there are fewer cases to look back to and draw conclusions from.

So how will this summer's El Nino affect the Mid-South?

Dr. Jeff Masters, who writes on Weather Underground's Wunderblog, recently discussed the same topic and recounted the effects of two similar cases in particular, the summers of 1982 and 1997. Both of these summers were generally cool and wet across a large part of the continental U.S. Both of these summers were slightly below normal temperature-wise in the Mid-South as well.

El Nino also tends to bring wetter than normal conditions to the southern U.S. owing to a persistent subtropical jet stream. Masters indicates that "signals remain positive for widespread summer moisture." In fact, NOAA's June-August climate outlook shows the Mid-South on the eastern periphery of a large area of cool and wet conditions that they believe will dominate the central U.S. So, despite short-term trends that indicate a warmer-than-normal start to June, the summer average could end up a bit cooler (not to the exclusion of some periods of hot weather that we know are in store!).

The June-August temperature trends (left) as forecast by NOAA indicate a better than even chance of cooler than normal temperatures across the central U.S. with the western part of the Mid-South possibly cooler than normal. Precipitation-wise (right image), a large part of the Rockies, central, and southern U.S. could be wetter than normal, including the Mid-South.

It's also worth noting that there tends to be a marked decrease in Atlantic tropical activity during El Nino summers as well, owing to increased storm-destroying wind shear in the favored tropical formation regions. However, that could be partially offset by elevated sea surface temperatures (SSTs) in the Gulf of Mexico and Caribbean. So while the overall pattern could be quiet this year, it only takes one storm to feed on higher than normal SSTs near the U.S. to cause big problems for coastal residents. Tropical outlooks for 2015 that have been issued so far have indicated a below normal season. NOAA's Atlantic basin outlook, released  May 27, calls for a 70% chance of below normal activity due to El Nino. More specifically, NOAA predicts 6-11 named storms, 3-6 hurricanes, and up to 2 major hurricanes.

We'll see how the summer plays out - it will definitely be interesting to monitor!

Erik Proseus
MWN Meteorologist

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A hot weekend, but another round of below normal temps is moving in!

The well below normal temperatures we've experienced for much of the month has resulted in this weekend's "normal" July weather feeling rather uncomfortable. Seems to be pretty easy to acclimate to cooler weather and take for granted the lack of 90 degree days. Then when a couple of days, such as this weekend, send the mercury into the mid 90s with heat indices very near Heat Advisory criteria, we realize just how fortunate we have been!

High pressure ridging into the area at the surface and aloft has resulted in a significant rise in the humidity levels and above normal high temperatures today, which will continue tomorrow. Be sure to take your Memphis summer heat safety precautions again tomorrow! However, the ridge retreats as yet another cold front pushes through, pushed to the Gulf coast by another building upper-level trough over the eastern U.S. This trough will bring below normal temperatures back into the Mid-South for the last week of summer vacation for many youngsters. Though not as cool as the last round, highs in the 80s, lows in the 60s, and dewpoints below average will once again bring a taste of early fall to the area.

The mid-level weather map (18,000') on Tuesday evening features a large trough over the eastern U.S. and huge ridge over the west. This has been the dominant pattern in July, which is very unusual for mid-summer and results in cooler than normal weather under the trough.

The cold front will move through Sunday night, but since most of the dynamics and cooler air aloft stay just to our north, a widespread severe weather outbreak will not occur. In fact, despite the low level moisture ahead of the front, the chances for rain are even fairly slim and confined to the evening hours on Sunday. Because the front will be pushing into a hot and humid airmass though, any storms that do form could bring strong wind gusts and brief heavy rain will also be a threat, in addition to lightning, Sunday evening. The best chances of severe weather will remain well to our north and east, especially in the upper Ohio River Valley where significant severe weather is possible. Here's our complete MWN Forecast for the upcoming week.

Severe weather will be likely in the Upper Ohio Valley, but is unlikely in the Memphis metro, outside of a stray thunderstorm with gusty wind and dangerous lightning.

Looking into early August, NOAA's 8-14 day outlook (covering August 3-9) indicates a high probability of below average temperatures continuing (see below). Note that the darker shades of blue do NOT mean colder, rather a higher probability of below normal temps. Here's to our good fortune from July continuing into August. (By the way, at this point, we also believe that the probability of reaching 100 this summer is very low. It's been 2 years this Wednesday since our last 100 degree reading.)

Temperature outlook for August 3-9 indicating a high probability of below normal temps in the dark blue shaded areas.

Erik Proseus
MWN Meteorologist

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