Saturday, February 27, 2021

Winter and snow in the rearview mirror, as spring rains arrive in the Mid-South

Many of us are suffering "weather whiplash" as spring seems to have arrived quickly once the snow melted! After setting multiple cold and snow records during a bitter spell in the middle of the month (average temperature of 19.8 degrees between February 11-19), much of Memphis saw the 70 degree mark on Tuesday and approached it again Wednesday. We've now entered a rainy stretch, as a frontal system wavers across the Mid-South from south to north and back south again this weekend. The wet period started with 2.20" of rain on Friday, with more to come. A Flood Watch is in effect for the metro on Sunday.



Saturday

The front that will be the focus for the heaviest rainfall this weekend starts south of Memphis Saturday morning with low clouds and patchy light rain with temperatures in the low 50s locally. As the day goes on though, that front starts to lift north as a warm front this afternoon. This will bring higher rain chances, and perhaps a few thunderstorms, to the metro mainly between 3pm-8pm. 

The surface map for Saturday into Saturday night, with fronts valid at 6pm Sunday. (NWS/WPC)


The warm front also brings warming temperatures and a return to southerly wind tonight. Expect to see the mercury rise to the mid 60s by late afternoon and then stay there overnight with a breezy south  wind. Once the front-induced rain moves to our north this evening, only spotty rain showers are expected overnight, with the focus of heavy rain shifting to our north. After 2" in the past 24 hours, we could see up to another 1/2" of rain with the front later today.

Sunday

The day dawns with very warm temperatures in the 60s, breezy south wind, and the warm front sitting well to our north. However, a cold front will make its approach during the day, overtaking the warm front and pushing through near sunset. Heavy rain focus in the morning will be to our north but a few showers are possible in the greater metro as temperatures make their way back to 70 degrees by lunchtime. 

The surface map for Sunday into Sunday night. The fronts are valid Sunday morning, with a cold front to our northwest poised to move through early Sunday evening. (NWS/WPC)

During the afternoon, scattered showers become more numerous with daytime heating and the front approaching. With plenty of moisture in the air, a warm and unstable airmass in place, and sufficient wind energy overhead, expect the front to slowly move in by late afternoon. It will bring plenty of rainfall to already-saturated ground, as well as thunderstorms. A few of these storms could be strong. Right now, that threat appears to be late afternoon to early evening and includes strong wind gusts and an isolated tornado. A Marginal Risk (level 1/5) for severe weather is in place for the entire area.



Rainfall totals from Sunday morning through Monday morning could exceed 2" in spots and most will likely get at least 1.5", bringing the total for the weekend to around 2", locally more, for many of us.

Total rainfall as predicted by the NWS Weather Prediction Center from 6am Saturday through 6am Monday. Many of us will be near or over 2" for the weekend.


Next week

Rainfall taper off Monday morning and anything we get Monday should be light. Some sunshine may peak out Monday afternoon  with temperatures closer to average - mid 40s in the morning and mid 50s in the afternoon.

Another system moves through the region on Tuesday afternoon. Models disagree on its impacts due to their party line hold on the strength of the system. We'll go with scattered showers mainly Tuesday afternoon for now with temperatures slightly cooler than Monday.

Model data concurs on a dry and mild Wednesday with highs in the upper 50s after a cool start. Then we get more disagreement heading into the end of the week on rain/no rain. We have low chances each day for now until we see some model agreement and since it's still nearly a week out. Highs will generally be in the 60+ range with lows in the 40s. The magic 8-ball says "signs point to" a drier stretch after this week for a while!



So now that winter appears to be behind us (with "round 3 of winter weather" nowhere in sight, despite claims from at least one weather hype-site on Facebook earlier this week), it's time to begin turning our attention to spring hazards, including flooding and severe thunderstorms, as the pattern warms with the arrival of March - and just in time for Severe Weather Awareness Week in Tennessee! Enjoy your weekend and keep the umbrella and your MWN app with radar and the MWN Forecast handy!

Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Saturday, February 20, 2021

Temperatures and snowfall records set during the recent Arctic Outbreak

Now that we are back above freezing (at least during the day) and the #StupidCold Arctic Outbreak is receding, we can look back and see, statistically, just how cold and snowy it was. The following temperature and snowfall records are now in the books:
  • Coldest high temperature: February 14 (19°)
  • Coldest low temperature: February 15 (9°)
  • Coldest high temperature: February 15 (15°)
  • Coldest low temperatures: February 16 (1°)
  • Tied coldest high temperature: February 16 (18°)
  • Coldest low temperature: February 20 (9°)
  • Daily record snowfall: February 15 (4.0")
  • Daily record snowfall: February 17 (4.7")
  • Fourth snowiest four-day period: February 14-17 (10.0")
  • Tied for second - consecutive days with high temperatures less than 20° (February 14-16)
  • Tied for longest consecutive streak of days with high temperatures less than 32° (February 11-19)
  • The average temperature for the period February 11-19 was 19.8° - the coldest for that nine day stretch on record.
All data is recorded at Memphis International Airport, the official observation site for Memphis, TN.

Estimated snowfall over the past week. Graphic courtesy NWS-Memphis.

Average temperature anomaly (departure from normal) for the week of February 12-19, 2021. Data provided by the NOAA/NCEP Climate Data Assimilation System (CDAS). And yes, the cold across the central portion of the country appears to be "off the charts!" (WxBell)


Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Tuesday, February 16, 2021

One last gasp of #StupidCold as winter storm #3 arrives Wednesday

The #StupidCold Arctic Outbreak of 2021 continues to set records locally, while Mid-Southerners wearily look ahead to one more winter storm that hopefully brings closure to the 2020-2021 winter season. Let's dive in.

Record-breaking cold

Over the past few days, Memphis has broken the following temperature and precipitation records:
  • Coldest high temperature: February 14 (19°)
  • Coldest low temperature: February 15 (9°)
  • Coldest high temperature: February 15 (15°)
  • Coldest low temperatures: February 16 (1°)
  • Daily record snowfall: February 15 (4.0")
  • Consecutive days with high temperatures less than 20° (Tied for 2nd - February 14-16)
What also seems to be likely top be tied at this point is a 1940's-era temperature record for the longest streak of days at or below freezing. That record is nine days. Given forecast highs of 29 Wednesday and Thursday and 30 Friday, the current cold outbreak will likely be tie that record.

Round #3 overview

Of greater interest right now though is the third winter storm in the past week, which begins early Wednesday. Once again, we have another low pressure system tracking along the periphery of Arctic high pressure, along the Gulf coast, over the next couple days and coincident upper level energy in the form of a trough moving through the Mid-South. And once again, moisture will be abundant and lift generated by the trough will be sufficient to generate precipitation in a cold airmass. 



Temperatures in this system however will have moderated some from the President's Day storm when we were in the low teens. Most precipitation will fall with surface temperatures in the 20s, even upper 20s, though temperatures aloft will be similar. 

Precipitation begins with scattered snow showers, perhaps in the pre-dawn hours Wednesday morning, continuing off and on through the day. By mid-afternoon, the main upper level energy associated with this system approaches and precipitation will become steadier. Snow will likely come down fairly steadily in the early evening, though temperatures aloft will be warming closer to freezing. 

Areas southeast of Memphis are most likely to see these temperatures aloft climb just above freezing, which will result in a mix of freezing rain or sleet with the snow. In fact, much of north MS is likely to see a mix of snow and sleet or freezing rain during the evening. In the immediate metro, those temperatures aloft are likely to remain very close to, if not below, freezing throughout the entire event - resulting in mainly snow. Some areas along and south of I-40 in the metro could see freezing rain mix in with the snow Wednesday evening, but areas north are likely to remain all snow. 

The surface weather map from Tuesday evening through Thursday evening. Low pressure moves along the Gulf coast and a trough brings precipitation to a large portion of the eastern U.S. (NWS)


As the upper level disturbance moves east around midnight, upper levels will cool off again and precipitation will become all snow once again for the entire area. It will also likely taper off or maybe end for a bit late Wednesday night. However, the main trough will move through Thursday, bringing additional light , perhaps even steady, snowfall during the morning and early afternoon hours. 

How much, of what, and when?

The first round of snow on Wednesday will probably drop one inch or maybe two of fresh powder by sunset Wednesday. The "mixed precipitation" phase Wednesday evening could result in up to 2" inches of snow for those that only see snow. For areas that receive a mix of precipitation, up to an inch of snow and perhaps 0.10" of freezing rain with maybe a few ice pellets are expected. Finally, from midnight on, another 1-2" of snow seems likely. That results in a storm total 4-6" of snow for areas along and north of I-40 and an inch or two less snow and a glaze of freezing rain for areas closer to the state line into north MS by the time it ends Thursday afternoon.

NWS-Memphis graphic illustrating what precipitation types are most likely Wednesday night. 

The probability of impactful freezing rain (0.10" or more) is highest south of the metro. North MS has a 50% or higher chance of that happening. In the immediate metro, 0.10" is about the highest we would expect. (NWS/WPC)

The probability of 4" or more snow with this system is highest west of Memphis, however there are 40-50% chances of this occurring in Memphis. Chances quickly drop off south and east of the city. (NWS/WPC)


Boom and bust?

If this system overperforms and the temperature profile remains below freezing for the entire event, 6-8" of snow is possible. If it moves through quicker and does not tap into as much moisture, the low end seems to be 2-3" of snow. Finally, if air aloft warms more than anticipated further north into the metro, we could be looking at up to a quarter of an inch of ice and the lower end snow totals (a couple inches). Model consensus still lacks a bit, but the confidence level for the forecast in the previous section is fairly decent.

This graphic shows, based on probabilities, the snowfall "Boom Forecast" - in other words, everything comes together perfectly. These amounts represent the 90th percentile forecasts, or there is only a 10% chance these amounts would be exceeded. For Memphis, that is around 6". (NWS/WPC)


Looking ahead

Once the system departs, fresh snow and high pressure building back in with clearing skies Thursday night will mean one more frigid night. Look for one last polar plunge as lows again drop to around 10 degrees with wind chills near zero Friday morning. 



However, with sunshine and that high moving in, temperatures will rebound into the upper 20s and melting will commence. The weekend looks decent with moderating temperatures (upper 30s Saturday and mid 40s Sunday) with a cold morning Saturday (mid teens) but back up to near freezing Sunday morning for the low. We'll be watching a chance of REGULAR LIQUID RAIN Sunday into early Monday. Cross your fingers we don't dip to freezing Sunday night! 



Next week, we return to near to above normal temperatures (which by the way is upper 50s during the day) and maybe - just maybe - winter will be over as we head towards the first of March! Take that, groundhog!


NWS Climate Prediction Center probabilities of above (orange) and below (blue) normal temperatures for the period from February 24-March 2. (NWS/CPC)


Stay warm and stay safe!

Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Monday, February 15, 2021

Another winter storm gone, time to look to the next one!

Winter storm #1 brought a thick glaze of freezing rain to the metro last Wednesday night and also ushered in the first round of sub-freezing air.  The prelude to storm #2 arrived yesterday as light snow throughout the day, coated over by a layer of sleet last night. This morning, heavy sleet changed to heavy snow - and my what a sight for an hour or so this morning as blizzard-like conditions reduced visibility and snow literally blew sideways! Generally, snow and sleet totals from this round varied from 3-7" and made for a nice snow day for most.

Now we turn our eyes to the next system in our triple scoop of #PolarVortex goodness. We'll see a lull for about 36 hours before that round starts early Wednesday and continues into Thursday. With temperatures "warming" about 15 degrees from second round levels in the 10-15 degree range, this storm presents a different set of challenges. Precipitation type appears to not be as straight-forward across the metro. 

While Arkansas appears to be cold enough to support straight snow once again, more of north Mississippi could get into a warm sector that supports rain. That leaves the metro in the crosshairs of the dreaded "mixed precipitation" phase for perhaps a lengthy period of time. With significant differences in the models, I'll do my best to let you know what is likely and what is less certain tonight. More information as we are able to provide it will be posted on our social media channels.

What we know

  • Temperatures will start very cold Tuesday night into Wednesday. Morning lows will be in the mid teens. By afternoon though, the mercury will climb to the upper 20s, perhaps to near 30, but will not quite reach freezing. Despite Arctic air receding a bit, lingering snow cover will keep the air from warming more than if we had bare ground.
  • Temperatures Wednesday night remain below freezing, but not nearly as cold as we're experiencing currently. In fact, with low pressure moving by over Mississippi and Alabama, they may not drop much at all Wednesday night. 
  • Colder air will again filter in Thursday on the backside of the departing system, with temperatures remaining in the 20s. Once it completely moves out Thursday night, we'll see lows again down in the lower teens to near 10 depending on fresh snow cover.
  • Precipitation may start as some snow flurries Tuesday night with light snow expected on Wednesday. A of now, it appears totals through Wednesday mid-afternoon will remain light. Potentially an inch or a bit more of snow could fall.
  • With low level temperatures staying cold and cold air aloft moving in behind the system, precipitation should fall on Thursday as snow as well before ending in the afternoon.


What is less certain

The main problem for this forecast is Wednesday night temperature profiles. With most precipitation falling Wednesday night, that presents a big "what if" scenario! Again, models present different scenarios and determining the most accurate is a challenge. So for now, the course of least resistance and most likely to be accurate is to expect a variety of precipitation types overnight. 

With slightly warmer temperatures southeast of the metro, the best chance for higher ice or snow amounts will be northwest of the metro, tapering to the southeast. Thus, the best chance for freezing rain and sleet will be southeast and snow or snow and sleet is northwest. With the precipitation amount (in liquid form) expected to be enough to produce impactful snow or ice amounts, I expect we'll be dealing with more (or continued) travel issues at a minimum, and perhaps even ice that could result in power outages or multiple inches of snow, depending on how it all plays out.

The probability of 0.10" of freezing rain for the period from 6pm Tuesday to 6pm Thursday shows how the metro could be right on the line of receiving significant icing and not. Probabilities range from 30-60% across Shelby County for now. (NWS/WPC)

Probabilities for 4" or more of snow range from 10-50% across Shelby County between 6pm Tuesday and 6pm Thursday. These two graphics demonstrate how uncertain the forecast is for now. (NWS/WPC)

[ UPDATE: As of 8:50pm Monday, a Winter Storm Watch has been issued from Tuesday at midnight through 6pm Thursday. The graphic below depicts the initial forecast amounts from the National Weather Service. Heaviest snow is expected west of the river, while a few inches is possible east of the river, in addition to some freezing rain. ]



For now, plan on an inch or so of snow Wednesday on top of what is left from storm #2 (likely most of it), a variety of precip Wednesday night that could leave us waking up to significant impacts once again, followed by another layer of snow (maybe another inch or two) to top it all off! Any accumulations on top of what we already have will result in potential infrastructure damage and, at a minimum, even more inconvenience. Plan accordingly and keep everyone, including the pets and pipes, warm for the next few days!

The good news is that we will be seeing sunshine return Friday and Saturday with moderating temperatures .We'll rise above freezing by Saturday and end what will likely be the longest stretch of sub-freezing days on record in Memphis! And I think we'll all be extremely grateful as we head towards March and warmer days.

Erik Proseus
MWN Meteorologist

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Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Sunday, February 14, 2021

Valentine's Mid-Day Update on incoming #memsnow storm

I did a Facebook Live detailing what to expect over the next 24-36 hours, and peeked at the rest of the week. Here's the 15 minutes video:



Here is the latest forecast snowfall totals from NWS-Memphis:



And a few of the graphics from the presentation below. Please stay WARM and stay SAFE!







Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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

Saturday, February 13, 2021

Winter Storm Warning for the Memphis metro


A Winter Storm Warning has been issued from noon Sunday through midnight Monday night. In addition, a Wind Chill Advisory has been issued for tonight.

Timeline

Spotty areas of sleet, freezing rain, or snow are possible during the day Sunday. However, most precipitation begins by late afternoon, likely as sleet possibly mixed with some snow, and continue through the early overnight hours. A lull in precipitation is possible during the early morning hours before precipitation picks back up again Monday morning. Snow is expected Monday with some sleet possibly mixed in during the morning hours. The heaviest snow is expected from mid-morning to mid-afternoon before tapering off to flurries late afternoon into the evening. 

Accumulation

Up to 0.5-1.0” of sleet is expected, while 4-6” of snow is expected to top the sleet and lingering ice from Thursday’s storm.

Impacts

Travel will likely become very challenging to impossible by Sunday night. With bitterly cold temperatures and dangerous wind chills also expected (lower single digits tonight and again Sunday night through Monday), the remnants of the storm are likely to linger well into next week, when another winter storm is expected Wednesday into Thursday.


More details on this third system are yet to come, but it has the potential to also be a significant storm. Details on the forecast can be found in the MWN app and here.

Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Friday, February 12, 2021

First take on President's Day winter storm

For all of you who have been begging for winter - whether you wanted really cold temperatures, ice (why would you want that?), or a "real snow" - I hope a week from now you're satisfied. Winter has arrived and will be locked in for a good week. 

Before I get into our President's Day storm, I can't skip over the fact that it is going to get #StupidCold. Cold like we haven't seen in a couple of years and a duration  that hasn't visited the Memphis area in 20 years.  We've been below freezing since Wednesday evening and may not see 33 degrees again until mid to late next week. The last time we had five consecutive days below freezing was around New Year's 2001. 

A listing of all streaks of 5 or more calendar days in which the temperature did not rise above freezing since 1875. 2001 was the last time we reached 5. We may reach 7-9 days in this Arctic outbreak.


The current forecast low on Tuesday morning is 8 (I'm not missing a digit) with a wind chill below zero. That hasn't happened in 3 years (January 2018). Please take care of your pets, other people, and your pipes. Pipes on exterior walls can be a problem when the temperature approaches or drops below 20 degrees.



Moving on to the fun stuff... when will we get a REAL SNOW??  Monday

The general pattern

It's still a bit early, and once again we have model inconsistencies, but at 3 days out a definite pattern has emerged and now it's about nailing down the details as the storm starts coming into the range of our higher resolution models. In sum, we'll have cold air in place, low pressure tracking by well to our south, an upper level trough moving through the Mid-Mississippi Valley, and strong southwest flow bringing in the moisture aloft.

The Weather Prediction Center's thinking on the general pattern is shown below. That NWS graphic indicates the potential that more than 0.25" of liquid precipitation will fall in snow or sleet form between 6am Monday-6am Tuesday. The general ratio used for snow is 10:1 - meaning that 0.25" of liquid falling would be 2.5" of snow. For sleet, it's 3:1, which would equate to about 3/4" of sleet. We are currently right around a 50% chance of that happening, but I will tell you the model data would indicate that chance should probably be higher.

Probability of 2.5" of snow or 0.75" of sleet between 6am Monday and 6am Tuesday (NWS/WPC)

The details we can offer 3 days out

Cold air at the surface is a given - mid 20s for highs on Sunday, mid teens for lows on Monday morning, and near 20 Monday afternoon. Above us, it appears there will be a little bit of above-freezing air a few thousand feet up until Monday morning. Models indicate we could start to see some precipitation spitting down on us Sunday afternoon but slightly better chances are Sunday night. With that warm air above, I foresee sleet or a sleet/snow mix to start. By about sunrise Monday, as the stronger dynamics approach, that air aloft will cool to freezing and the stage will be set for snow. The even won't wind down until late afternoon Monday with some flurries likely lingering into Monday evening. 

The upward motion generated by the low pressure trough moving through will be quite impressive. The cold air is equally impressive. And the total atmospheric moisture will be more than sufficient as well. All good news for snow-lovers. The caveats are the track of the low which affects the temperatures aloft. If we were to be slightly warmer aloft, or for a longer period of time, we would get more sleet. If it starts colder than anticipated Sunday night, then we might start as snow earlier and the totals would be higher. 

For now though, I'm siding towards the cooler (and more reliable with the recent ice storm) GFS and NAM models. Thus, I believe we could see a thin layer of sleet covering the landscape Sunday overnight, then snow most of the day Monday. Heaviest snow is most likely from mid-morning to mid-afternoon. Snow amounts will be higher west of the river and lower east of the metro, but my early thinking is 3-5" of snow in the metro is realistic. It would not shock me if some areas see more than that. Believe it or not, the upper end of that range would put us in the top 25 snowiest days on record in Memphis.



Adjustments are likely as we get closer to the event and there will be model runs that forecast as much as a foot. If it seems too good to be true, it probably is! I am not one to knee-jerk changes to the forecast because of a single model run, but if I see trends in one direction or another, I'll adjust. Remember that wind chills during this event will be in the single digits - it will be #StupidCold.



Looking ahead, we'll probably just be recovering from the President's Day system when the next one arrives late Wednesday into Thursday. This one could be even more tricky as we'll be starting to emerge from the Arctic Outbreak, so temperatures will be crucial. Early trends are towards more freezing rain and sleet than snow, but it's a week out and we might just get some freezing rain and rain! 

More updates to come on social media. Follow our latest forecast in the MWN app or our mobile website.

Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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

Thursday, February 11, 2021

Snow sourced to a manufacturing plant? Plus a summary of today's ice storm

A dynamic winter storm system moved across the greater Memphis metropolitan area over the past 24 hours! Starting with the arrival of a light coating of ice last evening, the storm picked up steam in the wee hours Friday, arriving with a boom for many - in the form of "thunder-ice" about 4am! 



If you had "freezing rain, sleet, hail, and thunder simultaneously" on your 2021 Bingo card, congratulations! In actuality, a few strong cells did produce lightning, thunder, and in some spots small hail amongst the ongoing freezing rain in 30 degree temperatures! (And clearly, that can all happen at the same time. But you need just the right conditions, including instability riding over a cold and stable lower layer of air. Eat your heart out Jim Cantore!)



By the time precipitation tapered off mid-morning, about a quarter inch of ice accumulation was left behind, with scattered power outages and partially slickened streets, and widespread gratitude that it was not any worse. (See my Twitter feed for lots of pics of ice across the Mid-South, like the ones from @kwhoover and @LauraL311 below!)


Photo credit: @kwhoover on Twitter


Photo credit: @LauraL311 on Twitter

Later in the afternoon, as cold, damp air hung over the metro with pockets of freezing drizzle and mist in the air, some folks in Midtown started sharing their pics of steady snowfall. Looking at radar, it was clear there wasn't any widespread snowfall occurring (nor expected). However, a narrow plume of echoes was evident in a north-south orientation from the western side of north Memphis south over the western loop of I-240 and into Midtown. 

After a quick exchange with the NWS on the possible cause, it was determined that it could be coming from a factory or plant of some sort that was exhausting steam into the cold air. The introduction of a heat source and abundant moisture into an already moist and cold low level airmass could indeed result in man-made precipitation. The wind trajectory from NNE to SSW would move the saturated water molecules downwind where they would precipitate through a subfreezing airmass, resulting in snowflakes. Millions of them. 

So I quickly determined it was time to snow-chase, hooked up with my good friend and today's navigator, John, and we pointed the car towards Frayser. 




Below are a series of tweets I posted after the chase to show you visually what I saw.
So the answer is yes, man-made processes can indeed produce a change in the atmosphere that affects weather several miles away, at least in this "mesoscale meteorology" example!

For those wondering about the weather for the next week or so, we'll cover the #StupidCold temperatures and the potential for a few more winter weather events in separate blogs and our social media feeds as the crystal ball becomes clearer. In the meantime, check out forecast anytime via the MWN app (link to download below) and anytime the actual low temperature approaches 20 degrees, these tips might save you thousands of dollars:



Erik Proseus
MWN Meteorologist

----
Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: MemphisWeather.net on the mobile web or via the MWN mobile app
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