Severe Weather Awareness 2018: Tornado Safety

The El Reno, OK EF-3 tornado of May 31, 2013, taken from about one mile away by storm chaser Nick Hellums.

Tornadoes are violent columns of rotating air that are produced by severe thunderstorms.  Weak tornadoes produce wind of  65-85 mph, while the strongest (such as the Moore, OK tornado of May 2013), produce wind well over 200 mph and can be a mile wide or larger (the El Reno, OK tornado of May 2013 is the widest on record at 2.6 miles!). Not all severe thunderstorms produce tornadoes, only a small fraction do, but people should be alert for the possibility if and when a Severe Thunderstorm Warning is issued and take action when a Tornado Warning is issued for their location.

Tornado safety rules include:

• At home or in small buildings, go to the basement or storm shelter, or to a windowless interior room such as a closet or bathroom on the lowest level.  Get under something sturdy such as a table or heavy bed.
• Abandon mobile homes and vehicles for a sturdy structure. If there is no such structure nearby, lie flat in a ditch, ravine, gully, culvert, or a low spot with your arms and hands shielding your head, staying mindful of possible flooding as well.
• In large buildings such as at school, shopping centers, hospitals, or factories/warehouses, go to the predesignated shelter area. Interior hallways on the lowest floor are best. Stay out of areas with high roofs or large roof spans, as they typically offer little to no protection from tornadic wind due to weakly supported roofs.
• At school, children should follow the safety procedures established by school officials. These should include avoidance of areas with high roof spans and glass exposed to the exterior of the school. Children should crouch down next to a wall or under desks or tables and cover the head and neck with their hands.
• At all times, avoid windows or large panes of glass.
• If outside and sturdy structures are not available, try to drive to the nearest sturdy structure for shelter.  If one is not available, lie down in an area that is lower than surrounding areas (ditch or ravine if possible) with arms/hands shielding your head (being mindful of potential flash flooding).
• When taking cover, have shoes on, photo ID on your person, cell phone (preferably charged in advance) with you, and crouch down and protect the back of your neck with your arms and hands.

A Tornado Watch, typically issued for a large area such as several counties, means that conditions are favorable for the development of severe thunderstorms that can produce tornadoes. Stay tuned to NOAA Weather Radio, commercial TV or radio, and other trusted sources for warnings and watch the sky for the possibility of developing severe weather.  Have your plan ready should a warning be issued and be ready to exercise that plan on a moment's notice.

A Tornado Warning, typically issued for a small area in the path of a storm, means that Doppler Radar has indicated the likelihood of a tornado or a tornado has been sighted by spotters or law enforcement.  If you are in the path of the storm (sometimes called "in the polygon" due to the shape of the warnings that are drawn by the NWS), immediately find shelter using the rules above.

A Tornado Emergency is not a warning type, but is issued (usually following the original Tornado Warning) when a large and destructive tornado has been confirmed and is moving into a populated area.  The risk of destruction and fatalities is high and an elevated call-to-action is required.  Everyone in the storm's path should immediately take action.

Storm Shelters

MWN recommends Take Cover Storm Shelters to keep Mid-South residents safe in the path of the storm. We have become very familiar with Take Cover's high-quality products, as well as their outstanding customer service, and have no reservations about endorsing this fantastic company. You can learn more about Take Cover Shelters and their in-ground shelters, which are installed in a concrete slab such as a garage floor, at their website or on Facebook. Be sure to mention MemphisWeather.net when you contact Jessica!

StormWatch+ Alerts

In addition, a personal warning device that only alerts you if YOUR location is in the path of a dangerous storm is a MUST. We encourage you to add StormWatch+ to your MemphisWeather.net app. It will wake you up at night for the most dangerous situations and allow you to customize exactly what locations you want to be alerted for and what types of alerts to receive, as well as when you don't want to be bothered.  The MWN mobile app is available for iPhone and Android devices.

For more information and interesting statistics on Mid-South tornadoes, see this recent study and this comprehensive overview produced by NWS-Memphis. Graphics below published in the second link listed.

Mid-South tornadoes by month. The primary season is spring, but a secondary season exists in the fall. Tornadoes can occur in any month however. Courtesy NWS-Memphis.

Mid-South tornadoes by hour of the day. Most tornadoes occur in the late afternoon to early evening, though they can occur at any time of day. In fact, 46% of Mid-South tornadoes occur at night, which contributes to a high death rate. Courtesy NWS-Memphis.

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Severe Weather Awareness 2018: Lightning Safety

Severe Weather Awareness Week continues with a look at how to stay safe when lightning is nearby.

• Any lightning safety plan should incorporate the 30/30 rule. The 30/30 rule states people should seek shelter if the flash to bang delay/length of time in seconds between a lightning flash and its subsequent thunder is 30 seconds or less and that they remain under cover until 30 minutes after the final clap of thunder.
• Move inside a well constructed house, a large building, or an all metal vehicle. Stay away from electrical appliances and do not use a corded telephone (mobile and cordless phones are OK).
• If you are in a boat, get off the water and into a substantial building, or at least into an enclosed and all-metal vehicle with the windows up. If you're caught in an open metal boat, lie down in the boat with cushions between you and the metal sides and bottom.
• If you are caught outdoors, get down to avoid being the highest point for a lightning discharge. If you're caught in a flat open field or your feel your hail standing on end, crouch down and cover your head with your hands. That way, only your feet will touch the ground.
• Move away from motorcycles, scooters, golf carts, bicycles, tractors, and other metal farm equipment. Avoid wire fences, clothes lines, metal pipes, drains, railroad tracks, and other metallic objects.
• Avoid lone trees and the tallest trees. If caught in the woods, pick a small grove of trees as your shelter, and stand at least 5 feet from the trunk of the nearest tree to avoid flying bark if the tree is struck.
• Avoid standing in a small isolated shed or other small ungrounded structure in other areas.
• If in a group of people in an open area, spread out before you kneel down.

For most weather providers (especially the small fish like us), lightning data is one piece of weather information that can be hard to come by (especially in real-time). There are only a couple of providers of commercial lightning data in the U.S., which makes re-distributing the data cost-prohibitive for all but the largest commercial vendors. That is why you won't find lightning data on MWN.

The colors of the echoes on radar indicate the relative severity of the storm. On StormView Radar, anything colored orange, red, or pink has a fairly high likelihood of containing lightning. As we nowcast on Facebook and Twitter, we'll also be sure to let you know if a storm is electrified so that you may adjust your plans as necessary to maintain your safety.

Photo credit: Brian Anderson

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Recap of Saturday's severe weather, and more rain??

Given the first Enhanced Risk outlook for Memphis since May 27 (you recall the Memorial Day weekend Tom Lee Storm right?), we fared pretty well. Some of our neighbors not far to the north were not so lucky.

Sequence of events

A Tornado Watch was issued at 3:20pm - our first since August 31, 2017 - as a line of storms moved across Arkansas towards the metro. The most potent airmass would end up being just north of our area where Tornado Warnings were issued from northeast AR across northwest TN. Locally, Severe Thunderstorm Warnings were issued as far south as the I-40 corridor with straight-line wind generally peaking in the 40-50 mph range as the line moved through between 7-8pm, resulting in some scattered power outages but no major damage. By 8:30pm, the majority of the metro was receiving just rain, as the line continued pushing east.

Unfortunately, severe storms dropped at least a couple of tornadoes in northeast AR, the Missouri Bootheel, and northwest TN, including an EF-1 that affected Keiser and Osceola, AR and an EF-2 that struck Malden, MO.

Exclusive video - Keiser, Arkansas (Mississippi county) tornado. #ARWX pic.twitter.com/YkCOgNqeWH

— Todd Yakoubian (@KATVToddYak) February 25, 2018

Images of the Rodeway INN in Osceola Arkansas @3onyourside @NWSMemphis pic.twitter.com/q3MddtfJo2

— Ian Ripple (@Ripple1026) February 25, 2018

Judging the forecast

Below you can see the severe weather outlook issued at 8am Saturday morning by the Storm Prediction Center, overlaid by the preliminary severe weather reports for the day. Overall, this was an excellent forecast with nearly all of the reports within the Slight (yellow) or Enhanced (orange) Risk areas. You can make out a southwest-to-northeast "path" of the damaging storms across AR to areas just north of the I-40 corridor into central KY.

Our Friday morning forecast indicated the timing of the storms would be between 8pm-1am Saturday night. That was adjusted Saturday morning to between 6-10pm, indicating the primary threat would be damaging wind and flooding, followed by a low risk of tornadoes. Overall, I feel that worked out quite well.

Map showing the Saturday 8am severe weather outlook (color fill) overlaid by the severe weather reports received by Monday evening. (NOAA/SPC)

Looking ahead - more flooding?

While severe weather drew the most attention Saturday, precipitation that totaled 4-5" in the metro and nearly a foot in portions of central AR resulted in high rivers and tributaries and some instances of urban and flash flooding. River flood warnings continue across the region with the Mississippi River itself forecast to cross flood stage by this weekend and remain there for a couple of weeks, cresting about 2.5' above flood stage at Memphis.

Analysis of precipitation that occurred over the past week, ending Monday morning, February 26. Roughly 4-5" of rain fell in the metro in the past week. (NWS / WxBell)

The next system arrives Tuesday night and continues through Thursday morning and promises to be another soaker. There appear to be two periods of potentially heavy rainfall - one Tuesday overnight and another Wednesday evening into the overnight hours. During the day Wednesday, rain chances remain high but amounts should be more manageable. By mid-day Thursday, I'm expecting another 2-4" of rain, locally higher, to have fallen across the area, which should push us over the all-time February rainfall record of 11.14". We're currently about 1.5" shy of that record. Flood Watches are again posted for this time period and rivers will only continue to climb as water simply can't soak in anymore and will run off into drainage areas and then local creeks and streams that feed the rivers.

Once the system departs Thursday, sunny skies are on tap once again heading into the weekend. Could this be the first Saturday in nearly 2 months to be dry and sunny??

Severe Weather Awareness Week

This week is also Tennessee Severe Weather Awareness Week (SWAW), so be sure to check out our SWAW webpage with new weather topics being added daily, as well as our social media feeds where we are giving away free MWN apps and NOAA weather radios this week! In fact, find our pinned post on Facebook and enter to win one of those Midland radios on Tuesday night! We're also running a sale on StormWatch+ in the MWN mobile app - only $5.99! That's a ONE-TIME fee for peace of mind in the form of personalized notifications when hazardous weather threatens. Learn more by clicking here.

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

Severe Weather Awareness 2018: Flooding and Flash Floods

Floods and flash floods occur every year in the Mid South. River flooding occurs seasonally when winter or spring rains or torrential rains associated with tropical storms fill river basins with too much water too quickly. Flash floods occur suddenly, usually occurring within hours of excessive localized rainfall. These flash floods can become raging torrents which rip through river beds, urban streets, or valleys sweeping everything before them.

When a Flash Flood Warning is issued for your area, or the moment you first realize that a flash flood is imminent, act quickly to save yourself. You may only have seconds.

A Flood Watch means it is possible that heavy rains will cause flooding in the specified area. Stay alert to the weather, and think about what you would do if water begins to rise or if you receive a warning. Watch for development.

Sometimes, an Urban and Small Stream Flood Advisory (or Flood Advisory) is issued for urban areas when excessive rain from thunderstorms begins flooding low-lying areas, small streams, and areas prone to excessive runoff on roadways.

Be especially cautious when driving heavy rain and avoid areas where water is known to pool or flood during heavy rain. It only takes two feet of moving water to sweep your vehicle away, including pickups and SUVs and six inches of moving water to sweep a person off their feet.  Nearly half of all flood fatalities involve vehicles.

Flash Flood Safety rules

• Get out of areas subject to flooding. This included dips, low spots, valleys, stream banks, and flood plains.
• Avoid already flooded and high velocity flow areas. Do not attempt to cross a flowing stream on foot where water is above your ankles.
• If driving, know the depth of water in a dip before crossing. The road bed may not be intact under the water. Don't drive into a pool of water or where water is flowing. Water up to the bumper will likely stall a car.
• If the vehicle stalls, abandon it immediately and seek higher ground. Rapidly rising water may engulf the vehicle and its occupants and sweep them away.
• Be especially cautious at night when it is harder to recognize flood dangers. Heavy rain events frequently occur at night!
• Do not camp or park your vehicle along streams or drainage areas particularly during threatening conditions.
• Turn around, Don't Drown!

MemphisWeather.net has the information you need during potential and ongoing floods and flash floods via the MWN Flood Center, which includes current radar and estimated precipitation totals, precipitation forecasts (amounts and timing), and river levels and forecasts. In addition, StormWatch+, available via the MemphisWeather.net mobile apps for Android and iPhone, will alert you if you are in, or drive into, an area that is under a Flash Flood Warning.

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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

Severe Weather Awareness 2018: SKYWARN Spotters and Social Media Reporting

Though severe weather often occurs within a defined "season" in the spring to early summer (plus a secondary "season" in the fall), as we saw on February 24, 2018, severe storms can strike during any month of the year at any time of the day or night. When severe thunderstorms threaten, the National Weather Service calls SKYWARN volunteers into action. SKYWARN volunteers are the eyes and ears of the National Weather Service, providing instant reports of severe weather, including hail, high winds, and dangerous cloud formations.

SKYWARN spotters keep a close eye on the sky anytime severe thunderstorms approach. Many communities deploy spotters around the edge of the city and use their early reports of impending hazardous weather to warn the community. Some spotters relay reports from their home or business while other more adventurous volunteers brave the elements and try to get as close to the storm as possible.

Ham radio operators collecting storm reports from SKYWARN storm spotters in the field. Picture courtesy NWS.

Who are these SKYWARN volunteers? A large number of SKYWARN storm spotters in the Mid-South are Amateur Radio Operators, commonly known as HAMs. These public service minded individuals make ideal storm spotters since they have the ability to communicate their reports. They are willing to be trained and they have a real interest in helping the National Weather Service, and their local communities prepare for severe weather. Amateur Radio operators are on call 24 hours a day, 365 days a year, even thought they receive no compensation of any kind for their hard work.

Many other groups participate in the SKYWARN program, including law enforcement agencies, fire departments, utility companies, rescue squads, and the news media. Individual citizens are also trained as spotters, and are asked to relay their reports to the National Weather Service. Spotters are a vital link in the warning process, and it is important to have as many trained spotters in each county as possible.

How can you get involved?  You can attend a storm spotter training class in person or online to become a trained spotter. Each session is free, lasts about 90 minutes and covers basics of thunderstorm development, fundamentals of storm structure, identifying potential severe weather features and (more importantly perhaps) severe weather look-a-likes, what and how to report, and basic severe weather safety. Online options include watching a training session that was conducted by the National Weather Service in Memphis or an online spotter training course that is available with a free registration.

Want to attend in person? We highly recommend it! A schedule of upcoming classes in the Mid-South can be found here. In the Memphis area, a class taught by NWS-Memphis will take place on Tuesday, March 27, at 7:00pm at Lord of Life Lutheran Church on Poplar Pike in East Memphis. All current SKYWARN volunteers should attend as a refresher, while new volunteers are strongly encouraged to attend and learn how to be a spotter, what to look for, and how to report. The classes are free and open to the public, including teens and older elementary children who enjoy attending with their parents. You can learn more about the SKYWARN program from the NWS here.

In addition to being a trained spotter, Memphians can use their social media accounts to report severe weather to the National Weather Service (@NWSMemphis) or to us (@memphisweather1)! We make sure that any and all severe weather reports we receive are sent on to the NWS. The best reports include a geo-tagged tweet and picture of the severe weather event (storm damage, hail, funnel/tornado, or even winter weather), as well as short description.

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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!

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Meteorologist Erik Proseus is an NWA Digital Seal Holder

Morning update on today's severe weather timing and threats

Here is the latest information as of 10:30am Saturday on our severe weather threat for today.

Synopsis

A developing low pressure area will move across Missouri and into the Ohio Valley, dragging a cold front through the Mid-South. Ahead of the front, the atmosphere is destabilizing due to warm, moist air. Temperatures are expected to peak in the mid 70s this afternoon with dewpoints in unfamiliar territory for February - the mid to upper 60s. This means there is plenty of moisture available to feed storms and more than enough instability to cause storm to grow quickly once they are lifted by the approaching front. In addition, strong turning wind from the surface to the mid levels of the atmosphere will allow large storms to rotate, resulting in some supercells.

Timing

As the atmosphere charges up, scattered showers and a few thunderstorms are likely throughout the day. I expect the most widespread coverage to be north of I-40, and perhaps the metro, by mid-afternoon, though we already have some hit-and-miss activity on radar as I type. By this evening, an organized broken to solid line of strong to severe storms is expected to reach the western edge of the metro by about 6pm, moving across the metropolitan area between 6-10pm. There is still minor uncertainty in this timing, but expect storms sometime in that window.

The mid-morning (10am) run of the high-res HRRR model valid at 8pm tonight shows the line of storms extending through west TN across the metro and down the Mississippi River to our south. We have fairly high confidence in this scenario occurring within an hour either side of this time, although scattered storms will be possible all day. (WxBell)

Threats

Flash flooding: Moderate. Any storms that form today will be capable of very heavy downpours due to the high dewpoints at the surface and abundant moisture aloft. Flash flooding is possible during and after any storm, but especially this evening when torrential rain is expected with the line. Total rainfall amounts will be highly variable by location but prepare for over an inch tonight and additional during the day if you experience additional storms.

Damaging wind: Moderate. Particularly with evening storms, wind gusts could easily reach severe limits (58+ mph). Due to the saturated ground, it won't take as much wind to topple large trees. Falling trees will result in power outages. Plan ahead for that possibility. It is also worth mentioning that by late this afternoon and evening, wind outside of storms will also gust to 30+ mph from the south. Tie down anything outside that you don't want to donate to your northern neighbors.

The probability of  damaging wind within 25 miles of a point in the metro is 30%. This is the highest threat we face today, besides possible flash flooding. (SPC)

Tornadoes: Moderate-low. It's been some time since we've had a credible tornado threat. Today is one of those events. The wind shear in the atmosphere this evening will be supportive of rotating supercells that are capable of producing a few tornadoes. Southern and eastern AR into west TN is the prime area where this could occur. I own't call it "likely" that one occurs, but it's possible and you need to prepare for it. SPC gives us a 10% chance that one will occur within 25 miles of you - low, but well above the "normal storm baseline." In addition, they indicate that a strong tornado or two are also possible.

The probability of a tornado within 25 miles of a point in the metro is 10%. The black hatched area indicates where there is a 10% chance of a strong tornado within 25 miles. We are not expecting an outbreak of tornadoes, but a couple are expected somewhere in the yellow area. (SPC)

Hail: Low. The hail threat is low as there isn't a great deal of super-cold air aloft to cause it to form. Certainly any storm will be capable of small (pea to dime size) hail, but the threat of large hail is lower than the other threats today.

The probability of large hail is 5% in the western metro, lower elsewhere. Hail is a low-end threat with this event. (SPC)

Preparation

Having a plan ready to put into action and preparing as best you can ahead of time is key. Below are some safety tips to review, particularly since it has been several months since we've had a threat of severe storms. Where will you be this evening and what is the sheltering plan for that location if it becomes necessary to do so? Storms will be moving quickly from west to east - so know the counties to your west if they are mentioned relative to severe storms. In Shelby County, those are Crittenden, Cross, and St. Francis.

I expect a Tornado Watch to be issued this afternoon through the evening hours. Remember a WATCH means to prepare - severe weather parameters are coming together. A WARNING means to take action - a severe storm is imminent.

Charge your phones and other necessary "distraction" or "information" devices. Tidy up outdoors if able - clear debris from storm drains, bring in loose objects, make sure the pets are taken care of.

If you haven't already, download the MemphisWeather.net mobile app for the latest info from us. Our Twitter feed has a chronological timeline which will be continuously updated, and you don't have to have a Twitter account to just read it! Within the app, we also highly recommend you activate StormWatch+ for a small one-time charge so that you can get warnings pushed to you, but only if YOUR set location is within the warned area. You select the location(s) and warning types you want to receive! Remember that tornado sirens for Memphis and Shelby County sound all at once for any tornado warning in Shelby County. (Bartlett, Collierville, and Germantown: yours sound only when your municipality is in the warning.) Most other counties in the metro also alert based on the entire county. For more on setup of StormWatch+, you can view this video.

Finally, be sure to stay in touch with a local weather source today as the forecast could still change a bit and to make sure you have the latest updates. We'll be live-tweeting and Facebooking throughout the event so joins us on social media at the links below. Lastly, we encourage you to "be prepared, not scared!"

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

Severe storms may put a bow on this week's rainy pattern

The end of this week's rainy spell is in sight, but we have to get through the potential for a couple more rounds of showers and thunderstorms, as well as one distinct threat of severe weather. The past week (in fact, this month) has seemed to be one rain event leading into the next. Precipitation for the past 7 days looks like this:

Precipitation analysis since last Friday morning (2/16) shows about 4" of rain in the metro and much heavier amounts across central AR. (WxBell) 

So far this month, Memphis International Airport is nearing 9" of rain, which is just over 2" short of the all-time February record of 11.14". We'll definitely make a run at that record.

For today, a nagging frontal system remains generally right over the metro. We'll see continued chances of pop-up showers during the day, though it looks like the next potential "round" of showers and a few thunderstorms could be this evening. Highs today are tricky, depending on cloud cover (a few peeks of sun will be seen) and pop-up showers, but should end up nearing 70° for most areas. The rain chance this evening ends overnight as the region gets firmly entrenched in the "warm sector" of tomorrow's low pressure system that will eventually bring an end to the unsettled pattern we've dealt with this week. Warm sector means southerly wind, muggy air, and warm temperatures - so look for lows tonight to remain in the 60s.

Animation showing simulated radar from noon Friday through sunrise Sunday morning. A few rounds of showers and storms are possible with the "main event" on Saturday evening, likely before midnight. (PivotalWx)

Saturday will feature a chance of showers or a thunderstorm, mainly in the afternoon, but also some brief breaks in the clouds and gusty south wind that help push temperatures into the mid 70s. It'll be a good idea to use that time to secure any loose objects and clean out any leaves or debris that are blocking gutters or drainage areas. 

By evening, as the low pressure center moves by to our north, we'll see a round of strong to severe storms push through the metro ahead of a cold front. Timing of the strongest storms appears to be between about 8pm-1am, with the main threat lasting no more than an hour or so at any one location. Due to the strong wind fields at all levels of the atmosphere and very warm and muggy air preceding it, storms will be capable of damaging wind gusts, perhaps some hail, and a couple of tornadoes. The metro is contained within an Enhanced Risk (level 3/5) of severe weather. Yes, we are on the leading edge of spring severe weather season!

In addition to the severe weather risk, Saturday evening's system will likely produce an inch or more of rain in a short time period, enhancing the ongoing flash flood risk. Flood Watches remain in effect for the region and River Flood Warnings are in effect for some of the Mississippi River tributaries, as well as the main river itself. Always be cautious, especially after dark, when encountering water on roadways. Don't drive across water-covered roads! You don't necessarily know whether the road bed is intact under the water. In addition, due to saturated soil, it won't take as much wind as usual from thunderstorms to bring down trees (perhaps into power lines). I expect we could see some tree damage across the area Sunday morning, even perhaps from sub-severe level wind (say 40-50 mph).

Prepare now

Be prepared for the potential for severe weather after dark Saturday night. It's been quite a while since we have had a substantial threat from severe storms, so take the opportunity to review the safety tips above. We also highly recommend you download the MemphisWeather.net mobile app and activate StormWatch+ within the app for severe weather alerts delivered to you for the locations you are interested in. We'll bring you updated information on our social media feeds throughout the next couple of days, so you can always find us on Facebook or Twitter if you have questions or need the latest info! Links to our feeds are below.

Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook, Twitter, Instagram 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

If it quacks like a duck... (heavy rain expected)

Seems spring has sprung the past couple of days as we've reach temperatures in the mid to upper 70s both Monday and Tuesday. Monday's high tied a record set just last year at 77°. Today's record of 80° (also set last year) may be safe, but not my much. [Side note: the 80° reading last year on this date was the first time we had reached 80° in February in 32 years. We almost did it again today!]

A cold front approaches

The warm, moist air that brings 70s to the region will be the same water-loaded air that is responsible for periods of heavy rain in the coming 4-5 days. It all starts with a cold front that is literally separating winter from spring in the U.S. While the western U.S. shivers, the eastern U.S. is setting dozens of warm weather records. Near the boundary, rain, thunderstorms, and ice are falling as the front slides slowly southeast. (OKC dropped from 68° to 32° and freezing precipitation in just 3 hours!)

Early afternoon temperatures across the CONUS show clearly where the cold front is located. (WxBell)

Wet Wednesday

By Wednesday early morning, that front will move through the metro and the wet pattern commences. Tomorrow will be very similar to last Friday when a high temperature in the mid 60s occurred around morning rush hour and the mercury fell from there in rainfall. We will see temperatures above 60° around dawn, then fall through the 50s into the upper 40s by Wednesday evening with rainfall much of the day.

Though severe weather will not occur, we will likely hear some thunder around the time the front passes early in the day. The heaviest rain will likely occur Wednesday night as the "river of atmospheric moisture" above us is tapped by a passing upper level disturbance, effectively opening the spigot just a little bit further. Rainfall totals through Thursday morning will likely be in the 2-3" range or so for the metro.

NOAA's Weather Prediction Center forecasts approximately 2.5" of rain by Thursday morning. (WPC/WxBell)

A Moderate Risk (category 3 of 4) of excessive rainfall - enough to cause flooding - is forecast with our first round of precipitation Wednesday in to Wednesday night. Flash Flood Warnings are very possible as the event unfolds. (NOAA/WPC)

Thursday-Friday - a small reprieve?

Continued scattered showers are expected Thursday and Thursday night as the front lingers just to our south before pulling back to the north overnight as a warm front. Models have some disagreement on the rain chances Friday, with one camp showing rainfall remaining mainly to our northwest, while the European model is a little more aggressive with scattered storms on Friday. We'll call it TBD and tell you to be prepared for scattered precipitation! Temperatures will still warm up nicely into the lower 70s.

Saturday-Saturday Night - Wet Again

By Saturday and Saturday night though, we'll be moving into round 2 of heavy precipitation. As low pressure moves by to our north and that warm, moist airmass has re-established itself over the Mid-South, showers and thunderstorms will break out. A few storms have the capability of becoming strong with some hail or strong wind gusts possible, mainly during the afternoon and evening hours. With heavy rain also expected though, it's possible that the air may not be unstable enough to generate severe storms. Stay tuned.

The severe weather outlook for Saturday is equivalent to a "Slight Risk" of severe storms, or category 2 of 5 risk. This could change as we draw closer in time though. Follow MWN for the latest. (SPC)

Either way, the Mid-South could easily pick up another couple of inches of rain before it moves out with a frontal passage late Saturday night, yielding a 5-day total of 3-6", or an amount only a duck could be happy about...

Flood Watches are in effect for the entire area (including Memphis and Shelby County) through early Sunday morning . If you live in, or travel through, areas subject to flooding during heavy rain events, that will likely have again this week. As as reminder: "turn around, don't drown." The only way to ensure your safety is to stay out of the water.

Sunday brings a return of dry weather that should last through early next week. Hopefully, some good drying will take place with mild conditions. By then, the all-time February rainfall record (11.14") could be broken however.

River flooding

We'll also be watching the river levels in the area. With the expansive reach and overall amount of water that will fall over the coming week, rivers will be high and could also flood some areas. The spring flood season is starting, including watching the Mississippi River rise as we head into early March. It will also likely eclipse the low end of flood stage and could have ramifications for low-lying areas, including along its tributaries (the Wolf, Loosahatchie, and Nonconnah rivers).

Stay with MWN for the latest on the heavy rain threat(s) via our social media feeds and mobile app with the human-powered MWN Forecast (links below). We'll keep you updated throughout!

Erik Proseus
MWN Meteorologist

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Wet weather and roller coaster temps on the way!

It felt a bit like spring on this Valentine's Day with warm, muggy, and wet conditions. While that will be a trend that we'll get a lot of in the next week or more, there is one major front that will disrupt the pattern on Friday. Let's dig a bit into the details.

Thursday

After a night in which temperatures remain in the 60s and south wind increases, Thursday will be the warmest day of 2018 to this point with highs projected to be near 75°. Rain chances will be minimal but southwesterly wind gusts will reach 30 mph in the afternoon hours. Clouds dominate the skyscape.

Thursday night - Friday

With a cold front remaining to our north Thursday night, another very warm night is in store, though rain chances will increase a bit as we head into the early morning hours. Southwesterly wind keeps the mercury above 60° all night long. Friday is one of those "upside down" days - and not necessarily pleasant! A significant cold front arrives in the morning, maybe by 8am, and triggers temperatures to plummet, in addition to rain. Despite the potency of the front, thunderstorms are not forecast, as most precipitation will fall after the front passes. Rain totals of less than a a half-inch are expected. Temperatures will fall quickly into the upper 40s with the morning frontal passage, then continue to slowly fall throughout the day. By evening, we'll likely be in the upper 30s with a wind chill near freezing, after starting the day near 60°.

Forecast temperatures at 6am Friday as a potent cold front moves south through the Mid-South, dropping temperatures from the lower 60s overnight into the 40s during the day. (WxBell - 3km NAM model)

Saturday-Sunday

Despite the temperatures residing in the 30s Friday night, most precipitation will take a break. On Saturday though, rainfall returns on the cool side of the front with temperatures in the 40s throughout the day. Another chilly, wet day.

Overall, Sunday appears to be mainly dry, though clouds will linger and a few showers can't be ruled out. It will start to warm back up though as Friday's cold front returns as a warm front and helps lift temps back into the 50s.

Monday-Tuesday

The start of the work week returns us to a warm, but unsettled pattern. As high pressure builds off the Atlantic coast, the favored region for precipitation will be around its perimeter. Depending on the strength of the high, that "perimeter area" could be right over the Mid-South, meaning continued chances of showers, perhaps some thunderstorms, and an increasing concern for flooding in low-lying and urban areas, as well as along local streams, creeks and tributaries that feed the Mississippi River, as rainfall totals for the week approach 3"+. Some areas by mid-week next week could see week-long rain totals of 6" or more. This will be in addition to the 5" of rain we have already received this month, which is already above the average for the entire month! Quack.

Total precipitation forecast by the NWS through next Wednesday is 3-4" across the Mid-South. Some local areas could see more than that. (WxBell)

Looking further out, the pattern is trending towards a continuance of generally warm and wet conditions right through the end of the month. Could it be an early spring? Or will March bring a now-almost-expected cold blast or two? We'll have to wait and see!

NOAA predicts a high likelihood of above average temperatures for the last week of February.

NOAA predicts a good chance of above average precipitation for the last week of February as well.

Stay in touch with the forecast conditions, and a very busy radar, with the MemphisWeather.net app. We'll have the latest information via our always-current social media feeds. All links are below!

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