Sunday, November 27, 2016

Cyber Monday Storm details - video forecast update

Cyber Monday will bring the threat of very heavy rain and potential severe weather to the area. In this video forecast discussion, we break down the timing and threats and then get into some detail on the meteorology of the event, concluding with the week-ahead forecast. You can get the gist of the necessary information in the first 6 minutes, but stick around for the "nitty gritty!"

If the embedded video doesn't work, you can watch on YouTube here.

Here are a couple of the graphics used during the video for those that want a brief overview.

NWS WPC forecast rainfall amounts through 6pm Monday. The metro can expect 2" of rain with some areas seeing up to 3".

The severe weather outlook from the Storm Prediction Center shows a Slight Risk (category 2/5) from Memphis south and a Marginal Risk (category 1 threat) for west TN and north AR.

Be sure to download our mobile app for the latest information, including MWN StormView Radar, our human-powered forecast, current conditions, social media feeds (continuously updated and linked below) and optional StormWatch+ severe weather notifications for your specific location(s) of interest!

Erik Proseus
MWN Meteorologist

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Saturday, November 26, 2016

Cyber Monday storm to bring heavy rain, strong wind

I hope everyone has had a great Thanksgiving weekend! It's been a cool, but not atypical, weather weekend with cloudy skies on Thursday and most of Friday and sun re-appearing today. Temperatures have peaked in the mid 50s the past couple days.

Sunday will see a return of high cloud cover ahead of the next storm system that is the main subject of this blog. Temperatures Sunday will start chilly - in the 30s - but climb to the mid 60s as south wind brings in warmer air.

On Sunday night, we'll begin to see the early stages of a major weather system that will traverse the Mid-South on Monday. Clouds thicken and lower and south wind increases further overnight with scattered showers moving into the metro before dawn Monday. The morning rush hour will likely be wet and breezy with temperatures in the mid 50s. This pattern continues through the morning hours with temperatures rusing into the low to mid 60s as dewpoints (humidity) continues to increase as Gulf moisture moves into the region on gusty south wind.

Forecast radar valid Monday at 6am showing showers over the region with heavier rainfall entering western AR, which will serve as the "main course" later in the day. All graphics courtesy
Monday afternoon and early evening will be the timeframe of greatest impact. A couple of factors will be key: 1) wind in all levels of the atmosphere will increase markedly as the day goes on, and 2) atmospheric moisture content will be very high (likely in the 90th percentile for this time of year). These factors will contribute to torrential rainfall rates and strong, gusty wind above 30 mph, especially after lunch into the evening rush hour. Though some thunder is possible, atmospheric instability is actually very low with this system, despite impressive atmospheric dynamics. High rainfall rates could actually help drag some of the wind from a screaming low level jet stream (up to 65-75 knots [75-85 mph] at 5,000 feet) down to the surface, which could result in some severe level gusts without thunderstorms actually occurring. In addition to the strong surface and low level wind, a very strong upper level jet stream of 150 kts (>170 mph) will be over the area, helping to increase the overall strength of the system. From an atmospheric moisture perspective, precipitable water values (a measure of the amount of liquid water in a column of air) near 1.50", or near record territory for this time of year in the Mid-South, will contribute to high rain rates and precipitation totals that could easily exceed 2" in most areas of the metro from early Monday morning through evening.

At 3pm Monday, the NAM (North American) model shows weak low pressure in eastern AR with surface wind in the 25-30 mph range (pinks) on its eastern side over the metro.

A little higher up, 3pm wind at 850mb (about 4,300') is forecast to be approaching 75 knots, or 85 mph, which are extreme values. Some of that wind could be "drug" to the surface by intense rainfall, resulting in severe wind gusts. 

Higher yet, at the jetstream level (200 mb or about 39,000'), Monday afternoon wind is forecast to be near 175 mph. This is about as strong as the jet stream wind gets in the winter time in this part of the country and will aid the overall system strength by creating divergent wind at this level, which acts like a vacuum cleaner, "sucking" the lower level air into the upper levels. 

Precipitable water (PW) values near 1.50" are in the 90th percentile for this time of year. PW represents the amount of  moisture in a column of air and values this high are supportive of high rainfall rates.

The Global Forecast System GFS/American) model forecasts 2.80" of total rainfall on Monday with a swath of very heavy rain across the Mid-South. Though 6-9" of rain are needed to completely alleviate the severe drought conditions in place, this would certainly help the situation!

The National Weather Service Weather Prediction Center forecast calls for over 2" of rain through Monday over the metro. (WxBell)

 To recap, the key takeaways for Monday are:

  1. Expect increasing rain intensity and wind values peak in the late afternoon hours.
  2. A few wind gusts to severe strength (60 mph) are possible due to very strong wind fields aloft.
  3. Total rainfall of 2"+ is expected with some areas of ponding likely, especially around afternoon rush hour. Flash flooding is possible, despite recent drought, due to rainfall intensity.
  4. Hail and tornado probabilities are low, but not zero.
  5. Plan for a wet commute in the morning and possibly hazardous weather for the afternoon commute.
By late Monday evening, we expect the system to pass, wind to let up a fair amount, and rain to stop. Exact timing can still change and will be updated as necessary. Stay tuned to the MWN mobile app and our social media feeds for the latest information.

Erik Proseus
MWN Meteorologist

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Thursday, November 24, 2016

Weather 102: Why is our cloud cover staying in place so long?

Thought I'd do a quick explainer on why it was cloudy all day today after forecasts yesterday indicated we might see some afternoon sun, and why I think we could have a repeat for most of tomorrow.

A forecast sounding is basically a cross-section of the atmosphere from top to bottom over a certain location. The high-resolution Rapid Refresh (RAP) model sounding valid at 4pm Friday (below) is very similar to what the atmosphere has looked like today and will continue to look like through most of tomorrow.

A layer of high moisture content air (greater than 95% relative humidity) exists in the lowest couple thousand feet above the ground. This moisture is "trapped" below a temperature inversion, meaning temperature increases with height above it. That inversion effectively places a "lid" on the air below it as increasing temperatures with height create sinking air. Cool air from the north is advecting, or moving, in below the inversion, keeping it cool in the lowest couple thousand feet. If you were to fly out of Memphis today or tomorrow, about 60 seconds after take off, you would be above the clouds and it would be sunny - they're not very thick!

Until the low level air can warm up, breaking the inversion, or the moisture can diminish due to drier air moving in, the clouds remain in place. On Friday night, and to a greater extent on Saturday, we will see the low level wind increase and much drier air arrive in the low levels, allowing the clouds to break up and resulting in a mostly sunny day for Saturday as high pressure builds overhead. Check out latest forecast via the MWN mobile app.

First glance at possible severe weather

Looking ahead, we'll be watching the Monday-Tuesday timeframe very carefully. Longe range global models are still in disagreement on the details, but it appears that the next major weather system will move through the Mid-South. Heavy rain (potentially a couple inches) and possible severe weather are both in the cards sometime between Monday afternoon and Tuesday afternoon as low pressure moves very close, if not through, the Mid-South and the atmospheric wind field really cranks up.

Check in throughout the weekend for updates on our social media feeds. Last Friday's storm served as a wake up call that we are in the midst of secondary severe weather season. After a relatively boring few months, the pattern has definitely shifted to "more active" mode!

Hope everyone had a great Thanksgiving! We are grateful to all of you for your support throughout the year and wish you all a great holiday season!

Erik Proseus
MWN Meteorologist

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Monday, November 21, 2016

Recapping Friday's storms, plus our Thanksgiving Week forecast

Happy Thanksgiving week!  I know many of you a are traveling, and if not, perhaps others are traveling to see you. There's also a big football game at the Liberty Bowl on Friday morning with the host Memphis Tigers taking on the Goliath-slayers, the Houston Cougars, on national TV. We'll get to all that in a minute. But first...

Secondary severe weather season

A strong storm system moved through the metro late Friday afternoon during rush hour. Though we were expecting thunderstorms and perhaps a few strong wind gusts of 40 mph or so, one cluster of cells in particular picked up steam as it entered Memphis proper and moved northeast into the Bartlett, Lakeland, and Arlington areas of Shelby County. The storm hit with a vengeance at MWN in Bartlett at 5:18pm with estimated wind gusts of 60 mph, wind-driven hail around the size of nickels, and torrential rainfall. Shortly thereafter, a Severe Thunderstorm Warning was issued for northeast Shelby County and points northeast of there. Trees were snapped and well over 25,000 MLGW customers lost power, some for as long as 15 hours. In addition, there was a large home that burned in Bartlett, possibly the result of a lightning strike (though not confirmed as of this writing).

This storm system should serve as a reminder that November to early December is secondary severe weather season in the Mid-South due to strong weather systems sporting large temperature gradients moving through. Severe weather this time of year is NOT rare! (Ask the folks of Germantown about their Thanksgiving weekend tornado of 1994.) Even in a drought, a large change in airmasses is still a trigger that can produce severe weather with the right storm ingredients in place. This storm system didn't care about our severe drought. We're fortunate it wasn't worse.

The impact graphic we posted late Friday morning advising of the potential for strong wind. The storm hit in the middle of our window of potential impact. Storms were just stronger than forecast. A  Marginal Risk of severe weather indicates that the potential exists for a few severe storms, which is exactly what happened.

Thanksgiving week forecast

With the arrival of last Friday's cold front, we shifted to an atmospheric pattern more conducive to repetitive wether systems moving through the region than very warm and dry conditions under high pressure anchored over the southeast U.S. The high has broken down and the jet stream has shifted south, meaning that systems moving along the jet will be more likely to move through the middle of the country than the far norther reaches along the Canadian border. This, in turn, means more rain chances and also cooler temperatures.

The next cold front to affect the region will approach on Tuesday night, tapping into a stream of Gulf moisture and bringing high rain chances. The front will be fairly slow moving and thus rain chances will be more prolonged than Friday's system. In fact, rain chances begin late Tuesday evening and continue well into the day Wednesday. The period of heaviest rain will be after midnight through dawn Wednesday with scattered showers continuing Wednesday, as the cold front doesn't move through until mid-day Wednesday.

The upper level weather pattern valid Wednesday morning at 6am shows "ripples" in the overall flow, indicative of multiple weather systems moving along the jet stream (pink colors). The orange dashes indicate the position of an upper level trough moving east and behind a surface cold front moving into the Mid-South. (
Severe weather is not expected as the dynamics of this system are not overly impressive, though some rumbles of thunder are entirely possible, especially early Wednesday morning. Rainfall totals should end up in the 1/2"-1" range across the entire area - a welcome prolonged rain that should help the severe drought conditions a bit more.

NWS forecast precipitation totals for the next weather system arriving Tuesday night. A good steady rain should produce about 3/4" of rain. (WxBell)
Travel conditions for Wednesday look to be inclement from the Great Lakes south through the OhioValley into the Mid-South to the western Gullf Coast. Air travel through Chicago, Detroit, Indianapolis,and Houston could be affected, while the east coast and Atlanta look good. Regionally, for those driving within a few hours of Memphis, expect scattered showers with the best chance of dry weather heading west out of Memphis. The Plains, from Canada to Texas also look good, including Dallas.

Forecast rainfal amounts Tuesday night through Wednesday shows where inclement weather could affect travel the day before Thanksgiving. (NWS)
By Turkey Day, the sun will be back out with weak high pressure in control and temperatures near seasonal levels - around 60° for the high after a cool start to the day. It should be great weather for eating too much, then walking it off later in the day! Thanksgiving Day travel should be much better than the day before. If you have an interest in what to expect for the Macy's Thanksgiving Day Parade in NYC, temperatures will be near 40° with cloudy skies, light wind, and a chance of light showers.

Heading into Friday, another weak low pressure system moves by well to our north, but it appears to not have a moisture feed this far south. Plan on another seasonal day for Black Friday with the mercury in the 40s for early morning shoppers and in the 50s for the kickoff of Memphis vs. Houston at 11am at the Liberty Bowl. The high tops out near 60° once again. (Go Tigers!)

Friday morning's surface map, according to the American GFS model shows a dry cold front moving through the Mid-South followed by high pressure that moves into the region by Saturday from the Southern Plains. (WxBell)
Very similar conditions are expected Saturday as we'll be between weather systems once again. Sunday through the early half of next week also looks unsettled with more rain chances and perhaps a few strong storms depending on the model solution one buys into. Certainly a much more active pattern than we have seen in a long time! Stay tuned for details on any severe weather chances as we're now in tune with the possibility that it could happen this time of year! As always, you can get our latest thinking, plus radar, the MWN Forecast, and more in our mobile apps.

Erik Proseus
MWN Meteorologist

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Thursday, November 17, 2016

Game-changer! GOES-R weather satellite takes to the sky

A "game-changer" in the realm of earth observing systems, GOES-R is the first in a new generation of weather satellites. It heads to space on Saturday afternoon at 4:42pm CST aboard an ATLAS V rocket launching from Cape Canveral, FL. (Interstingly, the launch was delayed as Hurricane Matthew moved up the Florida east coast last month while the satellite sat in storage near the launch pad!)

The GOES-R instruments. The ABI is the "camera" that takes pictures of Earth. The GLM detects in-cloud and cloud-to-ground lightning. The other four sensors will provide a complete picture of space weather hazards that could affect daily life on Earth, such as radiation hazards, power grid fluctuations, and interference to communications. (NASA)

What is a geostationary satellite?

GOES-R is a geostationary weather satellite, meaning that it will continually hover over one spot over the equator as the earth rotates below. That point, yet to be determined, will be 22,240 miles above the Earth's surface. The National Oceanic and Atmospheric Administration's geostationary satellites are assigned letters sequentially prior to launch, then are renamed with a number once in orbit. GOES-R will become GOES-16 once it is in orbit. Additional satellites of the same series (GOES-S, -T, and -U) will be launched in the coming few years and become GOES-17, -18, and -19.

Why do we not know where exactly it will be positioned once in orbit? 

NOAA maintains a suite of three satellites that monitor the western hemisphere, with particular emphasis on North America and the United States. These include GOES-East (technically GOES-13), which monitors the eastern U.S. and western Atlantic; GOES-West (a.k.a. GOES-15), which keeps watch over the western U.S. and eastern Pacific; and an on-orbit spare (GOES-14) that can be utilized if a problem develops with a primary satellite and is used to provide additional scans of South America.

The current views provided by GOES-East and GOES-West. GOES-R will eventually replace one of these satellites once testing is complete. This is expected to take well into 2017. (NOAA)

GOES-R (actually GOES-16) will be placed into a temporary orbit nearly over Memphis at 89.5° west longitude for several months in order to make sure everything is working properly. We will start to see the first images from the brand new satellite while it is still in a test phase around February 1. Then, in about a year, it will become "operational" and take over as GOES-East or GOES-West, depending on which of the current satellites is in most need of being replaced. (My bet is on GOES-East, as it's nearing the end of its planned operational life cycle.)

So why is GOES-R a game-changer?

The GOES-R Series (GOES-R, S, T and U - the next 4 satellites to launch) represents the first major technological advancement in geostationary observations since 1994. The satellites will carry a suite of instruments to improve monitoring of both near-Earth and space weather. As compared to the current GOES satellites, the GOES-R imager (basically the satellite's camera that takes pictures of Earth) will scan five times faster with four times the image resolution (providing much greater clarity of the imagery) and three times the number of channels (16 different "visualizasations" of the Earth as opposed to the current five). GOES-R can provide images as frequently as every 30-60 seconds over severe weather events and scan the entire Western Hemisphere at a much-higher resolution than we get right now, and do it in just 5 minutes! Lockheed Martin, the builder of GOES-R, said that the satellite will transmit more data in the first six months of operation than was provided in the 45 year history of all previous GOES weather satellites!

What else will GOES-R do?

Besides seeing clouds from space in multiple channels, GOES-R will also produce products that can estimate rainfall rates (which is particularly useful in mountainous or low-population regions where radar and rain gauges are not as reliable), estimate hurricane intensity, determine whether clouds are made of ice or liquid water (which is important in the aviation industry), detect aerosols that lead to poor air quality, track volcanic ash (also a major hazard to aviation and currently not well-detected), and pick out forest fires and determine snow cover more accurately.

The "cloud top phase" product, as shown above, helps meteorologists determine whether the cloud tops are liquid, ice, or some variation of the two and can be used both day and night. (
In addition, GOES-R will carry the first operational lightning detector (the GLM, or geostationary lightning mapper) flown in geostationary orbit which will measure both in-cloud and cloud-to-ground lightning, rather than relying on ground-based sensors. Used in combination with radar, other satellite data, and surface observations, lightning information from GOES-R has great potential to increase prepartion time ahead of severe thunderstorms and tornadoes as "jumps" in total lightning often precede a garden-variety thunderstorm's transition to a severe storm.

GOES-R will also host a suite of instruments to significantly improve detection of approaching space weather hazards. The satellites will provide advanced imaging of the sun and detection of solar eruptions for earlier warning of disruption to ground-based power utilities, communication, and navigation systems.

Preparing for the next generation of satellite data

For meteorologists to utilize the new imagery, not only will advanced training be required to understand and properly use all of the new products, but ground systems to ingest the gargantuan amount of data that will be transmitted from the satellite is a significant challenge. The pipes will get full quickly! That's why, at least initially, only certain entities like NOAA and the National Weather Service and some research institutions will get all of the available data from GOES-R. The rest of us will likely not see EVERY image that the satellite beams down, but we'll still have access to much more data, at a much higher resolution, than ever before.

As you can see, GOES-R really is a game-changer for the weather enterprise. It has been said that this leap forward in satellite technology will be like going from black and white TV to HD in one fell swoop. I can tell you that there hasn't been this much excitement in the weather community probably since Doppler radar first came on the scene 25-30 years ago!

Erik Proseus
MWN Meteorologist

Reference material provided by NOAA/NASA at Visit the link for much more information on GOES-R.

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80s to 30s - welcome to fall in Memphis!

Temperatures this afternoon are above 80°, but it appears the record of 84° will stand for another year (at least). As a reminder, the average high for the week before Thanksgiving is about 20° cooler at 62°! The pattern does a major flip over the next 36 hours however. Look upstream at what's behind the cold front coming our way...

Northern Plains radar at 2:45pm CST Thursday. (Intellicast)
Yes, that's snow, and it's spreading across the northern plains and towards Minnesota over the next 24 hours. A sure of sign much colder air behind the front! The air remains warm and mixed by south wind overnight as lows likely won't drop much below 60°. Then we'll have one more warm day Friday as a pre-frontal airmass remains over the region with temperatures rising into the mid 70s on a gusty south wind. A few showers could pop up by early afternoon.

By mid-afternoon Friday, the cold front approaches from the northwest and rain chances increase. In fact, a few thunderstorms are likely as well. The best chance of rain will be after 3pm with the front crossing the metro around the rush hour Friday evening. A few storms could produce gusty wind, but overall severe weather is unlikely. The western half of the metro is in a Marginal Risk of severe weather (category 1 of 5), which is the best chance we've had in a few months, but still quite low. The primary threat, mainly to our west in AR, will be a stray thunderstorm-induced strong wind gust.

Once the front passes, rain will continue, probably steadily for a couple of hours in the evening, as temperatures begin their freefall through the 60s and 50s. By midnight, I expect rain to have moved east and cold air to continue to move in. Dewpoints fall from the lower 60s late Friday afternoon to around 30° by Saturday at dawn with lows Saturday morning near 40°. Friday evening will just be plain wet, windy, and getting colder. If you have plans, adjust as necessary. The rain will be a welcome sight though as the metro is now officially classified as being in "severe drought."

The weekend looks good, just MUCH colder. I anticipate highs in the mid 50s with a low Sunday morning near freezing in the city and likely into the 20s in outlying, rural areas with light wind. Early next week features slightly warming temperatures (60s) with another very cold morning Monday, then some moderation. It'll definitely feel more like November! A system mid-week next week could disrupt some travel plans, especially across the middle of the country, but by Thanksgiving we should be cool and dry in the metro once again. Check details in the forecast via the MWN website or mobile app (links below). We'll have more on next week later this weekend.

Erik Proseus
MWN Meteorologist

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Sunday, November 13, 2016

October 2016 Climate Data for Memphis, TN

October Recap

Hot weather, compared to average, continued from the summer deep into fall as October's average temperature bested the previous warmest ever by 0.5 of a degree. In addition, October continued a dry streak as most locations in the metro saw the majority of the month's rain on a single day. "Moderate drought" conditions covered the entire metro by the middle of the month. There was no severe weather, once again, in October.

Ranking of warmest Octobers on record in Memphis, with October 2016 easily moving into the top spot.

Memphis International Airport, Memphis, TN

Average temperature: 70.7 degrees (6.6 degrees above average)
Average high temperature: 81.9 degrees (7.5 degrees above average)
Average low temperature: 59.5 degrees (5.7 degrees above average)
Warmest temperature: 92 degrees (7th)
Coolest temperature: 44 degrees (22nd)
Records set or tied: Daily high temperature records were tied on the 29th (85 degrees) and 31st (87 degrees).
Comments: This month was the warmest October on record in Memphis at 70.7 degrees, beating the previous record of 70.2 degrees set in 1941. For the year, the average temperature is 68.8 degrees, which is the second warmest January-October period on record and just 0.2 degrees short of the warmest year on record to this point (2012).

Monthly total: 1.22" (2.76" below average)
Days with measurable precipitation: 5 (2.5 days below normal)
Wettest 24-hour period: 1.11" (14th)
Records set or tied: None
Comments: Despite a very dry month with most precipitation occurring on a single day, through the first nine months of 2016, Memphis International Airport has recorded 51.70" of precipitation, or 9.25" above average (122%). Dry weather for the past 60+ days though has resulted in drought conditions expanding and worsening across the metro.

Peak wind: North/30 mph (20th)
Average wind: 6.5 mph
Average relative humidity: 63%
Average sky cover: 40%

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

Cirrus Weather Solutions /, Bartlett, TN

Average temperature: 67.4 degrees
Average high temperature: 82.5 degrees
Average low temperature: 54.7 degrees
Warmest temperature: 92.6 degrees (7th)
Coolest temperature: 37.2 degrees (22nd)
Comments: None.

Monthly total: 1.32" (automated rain gauge), 1.31" (manual CoCoRaHS rain gauge)
Days with measurable precipitation: 4
Wettest date: 1.13" (14th) (via automated gauge)
Comments: None

Peak wind: West/18mph (9th)
Average relative humidity: 76%
Average barometric pressure: 30.11 in. Hg

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

MWN Forecast Accuracy

MWN average temperature error: 1.53 degrees
MWN forecast temperatures within 2 degrees of actual: 80%
MWN average dewpoint error: 2.16 degrees
MWN forecast dewpoints within 2 degrees of actual: 68%

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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It's a bird! It's a plane! No, it's Supermoon!

If you think there seem to be a lot of supermoons lately, you are right. But in the case of tonight, none have been more "super." Due to its historical significance and perfect viewing conditions, we rate this one a "must see!"

The October 2016 supermoon, as photographed by ANDe Demetriou of Gemini Multimedia

What is a supermoon?

Full moons vary in size because the Moon's orbit is not a circle, it's an ellipse. One side of the Moon's orbit, called "perigee," is 50,000 km closer to Earth than the other side, "apogee." This Monday's "supermoon" becomes full about 2 hours away from perigee, a coincidence that makes it as much as 14% bigger and 30% brighter than lesser moons we have seen in the past.
In other words, the full moon, which is naturally the largest visually due to full illumination, will also be near its closest point of approach to Earth while full.

Why is tonight special?

The last 3 full moons of 2016 are all "supermoons" as they all occur at or very near the moon's perigee. However, because the moon's orbit varies slightly, this perigee is closer than October's or December's - so the moon is even closer than the other supermoons to end 2016. In fact, it's within just 85 miles of the closest it can possibly come to Earth! This will be the "super-est" of moons since 1948, or 68 years ago, and it won't be this close again for another 18 years!

When should I go take a look?

Anytime during the moon's passage tonight will be great, but consider times nearest moonrise and moonset (see pertinent times below), when the moon already appears large due to the moon illusion which makes it appear bigger when near the horizon than when overhead. In addition, the actual time of the full moon is 7:52am Monday, so viewing it closer to Monday morning's moonset time will make for a fuller moon than this evening (though the actual difference is almost imperceptible). If you miss it tonight or tomorrow morning, Monday evening will afford another good opportunity as the moon will still be nearly full and skies should still be mostly clear.

Pertinent times to consider (all times in Central Standard)

Sunday evening moonrise: 4:42pm
Sunday evening sunset: 4:56pm
Monday morning moonset: 6:24am
Monday morning sunrise: 6:34am
Time of actual full moon: 7:52am
Monday evening moonrise: 5:30pm

More information can be found in this article on ANd be sure to share any pics you take of the Supermoon with us! I'm looking forward to checking out the "Superest of the Supermoons" tonight as well!

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

Thursday, November 10, 2016

Fall is here! Details on the forecast, drought, and frost/freeze dates

Fall is definitely here! Lows in the urban core this morning were just above 40°, but most areas outside the city were in the upper 30s while the coolest areas dropped into the mid 30s. On the northern outskirts of Bartlett, MWN recorded a low of 35° and we saw our first frost of the year on patchy spots on the grass and sheltered rooftops. More on that in a minute, but first...

The next few days...

Very nice fall weather continues today and Veteran's Day with highs near 70° and plenty of sunshine. A weak cold front moves through Friday night and helps to reinforce the cooler and drier air. Saturday's temperatures start in the mid 40s and only climb to about 62° with a northeast breeze. If you're going to the Memphis Tigers football game Saturday evening, you'll want to prepare for cool temperatures with a kickoff temperature in the mid 50s, falling to near 50° during the game.

Drought status

A bit of rain on Tuesday barely put a dent in the ongoing drought conditions. The map below shows the percentage of normal precipitation over the past 60 days. The Memphis area is near 25% of normal. Areas to our southeast are even worse. In fact, today Birmingham set an all-time "no rain" record. It's been 53 days since their last measurable rainfall!

The current drought conditions for the Mid-South are shown below. The drought intensity in the metro is unchanged for the past few weeks, continuing in "moderate drought" conditions. The lack of rainfall and recent warm weather will likely have a muting effect on (and delay) the fall colors in the trees. Burn bans continue in MS with some firer restrictions in west TN.

Remainder of November

Looking ahead, the long-range forecast through Thanksgiving shows pleasant temperatures that remain above normal through much of the next week, followed by a fairly significant frontal system late next week that should cool us down again heading into Thanksiving week. (Average highs this time of year are in the mid 60s and lows in the mid 40s. By Thanksgiving, we should be seeing highs near 60°.) The official MWN Forecast can be found anytime in our mobile apps or on our website.

First frost/freeze data

An additional note on first frost and first freeze conditions. Memphis International Airport's average first occurrence of 32° is this Saturday, November 12. At the Agricenter it is November 7. We'll definitely be late this year as above average temperatures continue. (For the record, the latest "first freeze" at the airport is December 11.)

Frost is a little more tricky as temperatures, wind, and moisture all play into whether frost forms. A breezy morning with a low of 33° won't produce frost, but a low-lying area with no wind and clear sky could see frost in the upper 30s. The National Weather Service uses 36° as a proxy for "first frost," which is reasonable. The average first frost at Memphis International is November 2, while at the Agricenter it is October 25.

More frost, freeze and snow records can be found on

Veteran's Day appreciation

Finally, a word of thanks to all of those who have served this country in the armed forces, whether in peace time or war, and those who continue to serve. We appreciate your sacrifices and those that your families make on a daily basis and will support you in whatever way we are able! In fact, be sure you're following us on Facebook or Twitter (links below) as we'll be giving away free MWN apps to our friends that are active duty or retired service members, as well as first responders, on Friday as a small token of our appreciation! Thank you and God bless!

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