Thursday, January 31, 2019

Goodbye cold weather! Hello rain.

As most probably noticed today, it was a chilly start but we made a dramatic warm up this afternoon, bringing our highs back into the 50s. The good news is, we are going to stay near or above average temperature wise. The downfall? We have numerous shots at rain coming up over the next week, so we are breaking those chances down in tonight's blog!

Tonight and tomorrow

Light, isolated showers move in tonight with a weak trough. Source: WeatherBell

The clear and happy weather we experienced today fades away overnight tonight. A weak trough dives in from our northwest. Along with it comes increasing clouds and a few very isolated showers that will move in after midnight. Those increasing clouds will serve as a blanket for the Mid-South and help hold in today's warmth. Helping those clouds out will also be a southerly wind pulling in warmer air from the south. These to two factors together will help keep us out of the 30s and allow temperatures to only drop to 42°.

Tomorrow will start with some of those light showers in the AM; however, they will be out of the Mid-South by lunchtime at the latest. Clouds will be a different story and will hang around throughout the day. Temps will be very nice despite the rain, as we warm to 55°. Also, no worries! There isn't cold air behind tomorrow's system. By tomorrow night, clouds will start to break up as we drop to 43°.

This Weekend

If you are wanting to get any outdoors time this weekend, Saturday is a good day to do it! Temps will be very nice as we get lined up in the warm sector of a frontal system that starts to bring another chance of showers on Sunday. That said, Saturday we warm up into the lower 60s with partly sunny skies. Saturday night, clouds build as we introduce a very slight chance for a shower. Temps drop to only the lower 50s: NICE!

On Sunday, that frontal system brings the chance for a few stray showers during the day as ample moisture from the Gulf by this point will feed smaller convective showers. This will be far from a wash-out, though. Sunday we get even warmer, into the mid 60s. Even better, we only drop to the upper 50s overnight, meaning you can ditch all those blankets you had to bust out this past week for the wicked cool down.

GEFS (GFS Ensemble), as well as all other models, show that all our rainmaker for this weekend won't be anywhere near a wash-out. The probability of rainfall exceeding 0.5in. is zero for the Mid-South. Source: WeatherBell.

Monday and Tuesday

As if Mondays couldn't get any worse, this coming Monday brings increasing rain chances from Sunday as the initial frontal system pushes eastward and another developing one takes its place. This one's low pressure center will be situated further south, meaning that it will have more force/pull behind it. Rain chances increase throughout your Monday with what looks to be scattered showers until late that night into Tuesday. The best part about Monday is that we will be warming into the lower 70s with such ample southerly flow. Monday night, we drop down again only into the upper 50s.

Tuesday gets a little more difficult with the current model spread. The GFS model thinks that the front moves through, bringing some rumbles of thunder in the AM, then just remaining cloudy and gloomy for the remainder of the day. The European model thinks that the first front comes through in the AM, then quickly followed by another low developing behind the front (the GFS delays this low formation until Wednesday, and is weaker than the European model). This newly developing low could bring a secondary shot for rain late Tuesday and into Wednesday, and even bring the chance for a few storms into Wednesday. For now, we are going to conform to a slightly more European look and forecast the possibility storms for Tuesday morning, followed by a brief period of time with less precipitation, then that secondary low brings more rain into Wednesday.

Obviously we will keep an eye on how strong storms could be during this time period and keep you updated. Regardless of the rain, temperatures look nice at least, as they remain near 70 during the day and only drop to the mid 50s at night.

Wednesday and beyond

The Climate Prediction Center highlights the surge of colder air that is to come behind Thursday/Friday's rain. Below average temperatures seep into the area during the second week of February.
On Wednesday, models catch back up into semi-agreement that the low that forms back behind Tuesday's front will quickly move northeast, stretching a front out across a large portion of the U.S. that remains stationary over the Mid-South into next Friday. This front will lead to a few storms early to mid-day Wednesday, followed by decent rain chances from Wednesday into Thursday. With the front comes slightly cooler weather as we climb to the mid 60s (still well above average for early February). That night, models indicate that a much colder airmass dives south as the front pushes to our south.

We'll be watching the pattern carefully in case there is lingering moisture behind the front. This scenario has, in the past, produced a better chance of wintry precipitation than we have had lately with cold air chasing the moisture out of the area. That said, we are forecasting a cold rain for now and will continue to monitor.

Keep updated on the latest trends on our social media channels, and remember you can use the MWN app to check radar and the latest forecast anytime!

Reggie Roakes
MWN Meteorologist

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

Saturday, January 26, 2019

Looking ahead to Monday night snow and trailing Arctic cold

All eyes are on Monday night. I know because I have heard from you, especially the teachers out there! :-) But let's take a quick trip through the weekend before we delve into the arrival of yet another, more prolonged perhaps, cold snap.

Saturday and Sunday

A few flurries flew across the Mid-South last night as an upper level disturbance encountered some mid-level moisture. Most of us in the immediate metro wouldn't have guessed this morning though as the clouds cleared out and there were no signs of any wintry precip. With southwesterly wind today, highs are close to average for late January, or near 50. Some clouds are expected tonight, but overall a seasonal night is expected with lows remaining just above freezing. Sunday features more sunshine and highs near 50 once again, probably a couple degrees warmer than today with light wind.

Photo from Olive Branch Saturday morning, taken by former mayor Sam Rikard.


The next round of Arctic air will be diving towards the area Monday, but most of the daylight hours will be spent ahead of the front with temperatures well into the 50s after a morning low near 40 and gusty southwest wind contributing. Clouds will be on the increase though with a few rain showers possible in the afternoon. The cold front arrives around rush hour.

Monday night

This is where all the focus is, as the post-frontal airmass will be bitter and make its presence known fairly quickly. Temperatures plummet from the 50s to the 30s during the evening, escorted by strong northwest wind. Precipitation appears likely, but also not necessarily heavy. The better moisture ahead of and just behind the front lies to our southeast. Cold air will make a strong statement though. The question is how much moisture lingers as the "cold enough" air arrives to change precipitation from rain to snow.

The Saturday morning run of the European model, valid from mid-day Monday through Tuesday morning, indicates that areas south and east of Memphis could be more favored for light snow than we are, thanks to more abundant moisture. (

The nitty-gritty details

Friday, the models provided some hope for snow-lovers with forecasts of a couple of inches (perhaps more!) of the white stuff. But the synoptics (the overall atmospheric setup and progression of the pressure centers and fronts) are not of the type that typically favor much snow. [Aside: we like to see cold air already in place and a low pressure center move across the Deep South for healthy snowfall amounts. While lingering moisture behind a fast moving front from the northwest doesn't preclude snow, amounts are typically light as the dry continental airmass behind the front pushes moisture out quickly.]

Alas, the overnight and Saturday morning models seem to be recalling that situation, as well as lowering the expected atmospheric moisture overall. The snow-lover's dreams of yesterday are perhaps becoming their nightmares of "reality" today.

We're starting to move from the forecast time period where model ensembles rule the day to having a little more precise actual forecast guidance, now that we are within 72 hours, though ensemble data is still very much a useful tool.

Ensembles are basically a particular model executed multiple times (how may varies) with slightly different parameters that allows us to derive the probability of an event and therefore confidence in the forecast.

Here's what those ensembles say:

  • 12Z (Sat AM) GEFS Ensemble /based on the American GFS model/: Less than 1/2" of snow. Of the 21 "members" in the GEFS country club, only 8 vote for any accumulation at all and 4 have 1" or more. No teachers belong to this club apparently.
  • 09Z (Sat early AM) SREF Ensemble /based loosely on the American NAM model/: 1.5" of snow. Though if you throw out the 3 students that snuck in with votes of 4-6", that 1.5" drops to 1". Of those, only 7 of the remaining 23 members expect more than an inch.
  • 15Z (Sat mid-morning recount) SREF Ensemble: 1.8" of snow. Once again, throwing out 4 students or teachers with greater than 4", that 1.8" drops to 1.15" of snow, with a range from nothing to 3.5".
  • 00Z (Fri night) EPS Ensemble /based on the high-brow Euro model/: 1" of snow. Of the 51 EPS members, about half voted for 1" or a bit more. 6 will likely be expelled from the club for expecting more than 2". 
  • 12Z (Sat AM) EPS Ensemble: About 1/2" of snow. The number of members voting in favor of 1" or more dropped from 23 to 7 in this run and the number with more than 2" fell from 6 to 4.
  • Finally, the NWS Weather Prediction Center also has a probabilistic winter weather forecast. It currently indicates a 50% chance of 1" of snow and a 30% chance of 2" of snow (both down from early today). It also indicates that the most likely amount of snow right now is about an inch roughly along and south of I-40 with a "boom" amount (10% chance) of 2" and 1 bust amount of nothing.
Finally, the regular ("deterministic," or single run) model data says this:
  • 12Z (morning) American GFS: No accumulation. (And has been fairly consistent of late on that forecast.)
  • 12Z American NAM: Less than 1/2" with about an inch a couple counties south of Memphis.
  • 12Z European: No accumulation. (It had about 3/4" on last night's run.)
  • The high-resolution models are not yet within range of this event, but will start to be late tonight.
The NWS snow probability forecast indicates a 50% (or "most likely") scenario of about an inch of snow in the metro with higher amounts to our east. (NWS/WPC)

The verdict

Given the recent trends in the data, the ensemble guidance that is also lowering with each recent run, and the typically unfavorable synoptic pattern, I expect that light rain likely will change to snow Monday late evening, but I'm taking the "under" on a forecast of an inch of snow in the greater metro. There is obviously still time for this to change so stay tuned, especially to our social media channels, for future updates.


The potential saving grace for those who want their Tuesday interrupted by winter weather is the fact that there will be very little recovery Tuesday morning to improve conditions for whatever falls. Temperatures fall to the lower to mid 20s by sunrise Tuesday, and despite sunshine, highs may not get above freezing during the day. While wind and sun will take care of any *possible* accumulation in exposed areas, shady areas could see any snow linger. We could be dealing with some slippery conditions on Tuesday early morning. It's still too early to know for sure.

European model high temperature forecast for Tuesday. 31° in Memphis. (


An Arctic airmass will continue to envelope the northern and eastern U.S., with the Mid-South on its southern fringes. You will likely hear about this "polar vortex" over and over in the days ahead. While the bitter cold air is not the vortex itself, just a result of it, we won't argue semantics for now. Just know that temperatures will continue to be well below normal (some 15-20° below) for the mid-week period. But hey, at least it'll be above zero! Prepare for wind chills in the teens to perhaps single digits though, and highs in the 30s with lows in the teens to low 20s. The prolonged period of cold air should prompt you to consider protecting pipes, plants, people, and pets!

The GEFS ensemble (mentioned above) temperature anomaly (departure from average) at 5000' for the period from next Tuesday through Saturday. The 5000' value is used as a proxy for surface temperature and shows a massive area of well below normal temperatures next week in the central/eastern U.S. Values are in °C. (
Stay tuned for later details on Monday night's snow potential, as well the the Arctic blast arriving behind it!

Erik Proseus
MWN Meteorologist

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

Tuesday, January 22, 2019

Update on Wednesday's winter weather chances

After a semi-detailed blog yesterday that raised some hopes, it appears that Mother Nature may have pulled another fast one on us. In all actuality, a few degrees really DOES make a difference.

The main change to the forecast is that the arrival of the cold front ushering in the colder air looks to be delayed a couple of hours - instead of about 3am, it'll be closer to 6-7am Wednesday. That, along with a slight modification to the airmass coming in behind it, means that instead of temperatures dropping into the mid 30s during the morning, it will likely be into the afternoon when they get that low. Precipitation ends by late afternoon. Thus the "sufficiently cold" air that would result in a changeover to a wintry mix is pushed back to closer to when the precipitation departs. It's the age-old issue here in the South: rain moves out before cold air arrives...

So what does all that mean?  Simply put, Wednesday will likely feature a cold rain with a small chance in the mid-afternoon hours of a bit of sleet or snow mixing in with the rain. With temperatures still above freezing during the daylight hours (though cold), no significant impacts are expected, including to roads. The heaviest rain is likely just behind the front, or during the morning.

The Tuesday mid-day run of the high-resolution NAM model paints precipitation as rain for the event that starts this evening and continues through tomorrow afternoon (loop from 6pm Tuesday-6pm Wednesday). The chances of wintry precipitation are diminishing as we get closer to the event occurring. 

Precipitation should be departing by rush hour with a cold wind continuing, so roads should also dry out in the evening, precluding the formation of most ice overnight. A few areas, like we saw Sunday morning, could have patchy black ice on Thursday morning, but should not affect 99% of travelers/commuters.

You should still plan on temperatures falling during the day tomorrow. It will likely be in the 50s all night with a strong south wind blowing at 20-30 mph and scattered showers moving in this evening and continuing overnight. With the front arriving around 5-6am, steadier rain is expected for the AM commute with temperatures falling quickly through the 40s during the morning and into the 30s in the afternoon (with wind chills in the 20s). We'll drop to the upper 20s by Thursday morning.

We'll continue to post the latest information on our social media profiles. For snow lovers, you'll be happy to know that the longer-range pattern continues to indicate waves of cold air moving through the region over the next few weeks. Maybe one will collide with some Gulf moisture!

Erik Proseus
MWN Meteorologist

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

Monday, January 21, 2019

A winter reprieve, but another round of "precip" is on horizon!

9:30am Tuesday:  The information for Wednesday has been updated. Please see our social media feeds for the latest. Forecast impacts have decreased since this was published.

Winter definitely made itself known this weekend as light snow brought a coating of white the metro Saturday evening, followed by a sunny but cold day on Sunday with wind chills getting no higher than the 20s. That made for a cold night for viewing the total lunar eclipse last night, but it was still a sight to see anyway!

Monday-Tuesday, warming up

Looking ahead, we'll begin to warm up some today as wind shifts southerly ahead of the next system that arrives Tuesday night in to Wednesday. We'll get into the 40s this afternoon and remain above freezing tonight thanks to increasing southerly flow. Tuesday will be windy with the south wind increasing and gusts likely exceeding 30 mph during the day and overnight. Rain chances also move in by Tuesday late afternoon as highs reach the 50 degree mark. Rain is expected Tuesday night, some of which will likely be heavy.

NWS precipitation totals forecast between 6pm Tuesday and 6pm Wednesday. (via WxBell)

Wednesday, more winter precip

The cold front associated with all that rain arrives in the wee hours of Wednesday. Once again, like Saturday, precipitation will fall behind the front, as will the temperatures. Wednesday's daytime high temperature will be in the upper 30s at dawn with the mercury falling towards the freezing mark, perhaps by the noon hour if not shortly thereafter.

The falling temps mean a complicated forecast as far as precipitation type is concerned on Wednesday. A wintry mix of snow, sleet, and possibly some freezing rain will transition southeast into the metro during the day. There is still disagreement among the models on how fast the cold air arrives and when precipitation moves out.

The Monday morning high-resolution NAM model forecast radar projection for Tuesday evening through Wednesday shows the potential for some winter precipitation on Wednesday. (

What can we expect?

At this time, I expect we could see that wintry mix into areas along and north of I-40 by mid to late morning and south of I-40 by mid-day. With precipitation likely tapering off by mid to late afternoon, ice and snow amounts should not be excessive, but could be a bit problematic, especially in the case of any icing. Temperatures should get close to freezing by midday to early afternoon, so anything that falls before then would melt. After that, all bets are off. We all know that the presence of minor ice amounts can slick up elevated roadways and bridges fairly quickly. And once again, with a transition from rain, there will be no pre-treatment of the roads.

My best educated guess as of now, midday Monday, on amounts and timing (subject to revision of course):

How much: Snow and sleet - less than an inch. Freezing rain/ice - up to 0.10".
When: Transition to a wintry mix between 8am (north, or Tipton County) and 11am (south, or northwest MS) with precip ending by 2-5pm (west to east)
Impacts: Bridges and overpasses could become icy by the lunch hour into the afternoon. Minor accumulations of ice/snow on vehicles and other exposed surfaces (those that you saw snow on Saturday evening).
Confidence: In occurrence of winter precipitation and timing - Medium-High. In exact types and amounts - Medium-Low. In a "bust" scenario, the temperatures stay a bit warmer and we get more rain than wintry precipitation.

At this point, I urge Mid-Southerners to start considering plans for Wednesday, especially afternoon, and monitor the latest forecasts as the situation remains dynamic. The blog will be updated by Tuesday evening with the latest, but monitor our social media feeds for updates 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

Saturday, January 19, 2019

Saturday afternoon update on tonight's #memsnow

Updates at 3:45pm are highlighted.

The Arctic front has moved through the entire metro - and wasn't it a doozy? Temperatures were near 60° at 11:30am and now are in the lower to mid 40s (as of 2pm) with northwest wind routinely gusting to 30-35 mph. Memphis International recorded a 49 mph wind gust as the front passed.

Temperatures at noon Saturday clearly show the position of the Arctic front. (WxBell)
Behind the front, spotty light rain is occurring this afternoon as temperatures fall. The final "kicker," an upper level disturbance, will graze the area to our north later today, bringing with it one more defined round of precipitation. Temperatures near the surface and aloft will continue cooling, allowing that precipitation to fall as light snow this evening.

HRRR model forecast radar through 11pm shows the round of precip falling as snow in the metro and points north this evening. (
As far as amounts, impacts and timing, here's what we expect:

How much: a trace (over north MS) to 1/2" (Tipton County). That leaves most of us with a dusting  to 1/4" on cold exposed surfaces, mulch beds, etc. A bit of sleet is also possible as rain transitions to snow.

The NWS forecast from late Saturday morning of projected snowfall totals. Minor accumulation is possible roughly north of I-40. 
[Updated] When: Light snow or sleet could begin mixing with the rain by 3-4pm in Tipton County and 4-5pm in north MS, becoming all snow by 5-6pm, and ending by 7-9pm. It won't last long.

Impacts: Mostly just pretty! A brief burst of steady snow is probable between 4-6pm for an hour or so before tapering off. I'm sure it'll be delightful to look at. Roads will still be warm and wet, so they should not be a major issue. Use caution on elevated roadways in the metro and rural roads to the north, especially Tipton County. I don't expect huge problems, but just be mindful. Here is the NWS statement:

Confidence: High. Light snow is expected for most of the metro, timing is fairly well locked in, and amounts are agreed on by the vast majority of our model data, including most of the members of the model ensembles, which just means the models are run over and over and the results are all pretty well in line. Meteorologists use this ensemble data to gauge confidence in the forecast and see what the potential is from the "outliers." In this case, well over 80% of all of the available data likes the forecast above.

On Sunday morning, temperatures will be in the mid 20s with wind chills well down into the teens - a major departure from 24 hours previous when temperatures were about 55°! The wind will help dry streets overnight, but again, be cautious on the elevated overpasses and roads as the rain from today could freeze in spots overnight. That results in black ice.

Will this be our only chance this winter? In short - no. See our recent blog that described how cold air will dominate the weather pattern for perhaps as much as the next 4-6 weeks. There are a couple more systems just in the next week or so that will need to be monitored. No major storms on the horizon, but in this pattern, you just never know! Keep an eye on the MWN Forecast (linked below or in the app) for the latest.

Be safe and enjoy!

Erik Proseus
MWN Meteorologist

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Thursday, January 17, 2019

Arctic airmass intrusions and snow chances

While the cool, damp conditions and overcast skies of late are fairly normal for winter in Memphis, it appears Mother Nature may be poised to send "real" winter our way starting this weekend. While that means the collective antennae of Mid-South meteorologists are "up" for winter precipitation chances, the most likely result of this pattern change will be shots of Arctic air that intrude well into the mid-latitudes, including the Mid-South. Let's dive in!

Today and Friday - mild and mainly dry

Preceding the Arctic air, we'll get a taste of well above normal temperatures the next 48 hours or so, just to re-acclimate you to something semi-pleasant before lowering the Arctic hammer. Today's rain has shifted east for the most part with a weak Pacific cold front moving through late this afternoon. While that will briefly shift our wind around to the north, it won't get too cold behind that front. Look for lows to remain in the 40s overnight - no ice scraping in the morning! Friday will see continued mostly cloudy conditions, but most of the daylight hours will be dry with highs well back into the 50s as wind turns back around towards the south ahead of the next major weather player.

The NWS forecast chart for Friday shows low pressure to our west poised to move east with Arctic air on it's north side. A series of fronts are across the Mid-South. Most of the day will be dry but rain arrives by evening. (NWS)

Friday night through Saturday mid-day - warm and wet

Rain moves in Friday night with wind becoming gusty out of the south, which should hold temperatures up in the 50s during the overnight hours. A rumble of thunder is possible late Friday night into Saturday due to the strength of the incoming low pressure system and accompanying front. Rain continues into Saturday as we see temperatures rise to about 60 Saturday morning.

The NWS/Weather Prediction Center precipitation forecast for Friday at 6pm through Saturday at 6pm calls for more than an inch of rain for Memphis. (NWS/WPC)

Saturday afternoon/evening - the Arctic hammer

By Saturday afternoon though, it'll be as if Memphis was picked up and dropped 1000 miles north in Minnesota! That rude front will bring a doozy of an Arctic blast with temperatures dropping some 25 degrees by evening - into the 30s - and a north wind blows at 30+ mph! That's when things could get interesting for a minute as the Arctic hammer gets dropped...

While some precipitation will linger into the evening, the cold airmass could advance quickly enough to change the lingering precip over to the white variety. As of now (Thursday afternoon), I think we've got better than a 50% chance of seeing snowflakes after dark Saturday evening. However, I don't think it will amount to much. The dry Arctic air will wring out the atmosphere pretty quickly, and precipitation will be quick to exit. Accumulation chances appear to range from none to an inch with most of the metro likely to see 1/2" or less.

The NWS/WPC forecast as of Thursday morning for the "most likely" snowfall expected Saturday morning through Sunday morning. Note the 1" area sits just northwest of Memphis. (NWS/WPC)

The NWS/WPC forecast for a "reasonable worst case" (or best case?) for snowfall totals Saturday morning through Sunday morning. These values have only a 10% chance of being exceeded. So 1-2" is likely the most we could expect to receive and even that is not considered likely. (NWS/WPC)

Nearly all models are on board with the "less-than-an-inch" solution at this point. The holdout of late, our typically-esteemed European colleague, has lowered the potential as of this morning. The situation can still change of course, but that move brings it more in line with the American-bred models, raising confidence in the solution. More impact-ful snow totals and some ice is expected north of the Memphis region.

Sunday chill

By Sunday morning, all precipitation will be gone and clouds will be departing as well, but not the cold air! A brisk north wind will keep temperatures from rising much above freezing despite sunshine. That means wind chills in the teens in the morning and 20s in the afternoon. Brrr! One thing to be on the lookout for. especially Sunday morning, will be patchy ice. Temperatures drop quickly, after dark, immediately behind departing rainfall. It's conceivable that a "flash freeze" could result in spotty black ice. With lows in the mid-upper 20s and a stiff breeze blowing, I think our chances of that occurring are fairly low, but it's worth keeping an eye on.

Sunday night will be the coldest night of the forecast period as high pressure quickly builds in and shuts off the wind machine, allowing the mercury to dive, possibly into the teens outside the city.

Longer term - more of the same?

As quick as it turned cold, the Arctic high shifts east, "return flow" (southerly wind) re-engages, and we warm back up on Tuesday in time for an aftershock - more rain, warmer temperatures, and another Arctic front Tuesday night that could have us watching precip types again Tuesday night!

The week 2 (Jan 25-31) temperature probability outlook for the U.S. indicates well below average temperatures are likely for the eastern half of the nation. For Memphis, the Climate Prediction Center puts those odds at 77% for Memphis specifically. (NWS/CPC via PivotalWx)

The European model seasonal forecast indicates enhanced odds of below normal temperatures for the eastern half of the country during February. (

It appears that this pattern of rising and diving temperatures may continue a while, as we head into a period of generally (on average) below normal temperatures that continues well into February according to most semi-reliable data. Like I stated in a previous blog, the long-range trends continue to show below normal temperatures for the eastern half of the country from next week through the end of the winter season. We'll see what the groundhog has to say about that in a couple weeks!

Erik Proseus
MWN Meteorologist

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

Sunday, January 13, 2019

A weather smorgasbord this week, with an eye towards an Arctic air intrusion

We had a few nice days this past week with mild temperatures and some sunshine that allowed the ground to dry out a bit. Of course, that was followed quickly by more rain and, today, cold weather and dreary cloud cover. Looking ahead, we'll get a mix of clouds, some sun, cold weather, warming temperatures, and rain - all in the next 5 days. By next weekend, a significant pattern change is on the horizon.

Sunday night - Monday clouds

Despite high pressure building in, as we sometimes experience in winter with low sun angles and lots of low-level moisture, clouds will stick around tonight into Monday. We stayed near 40 today with a cold wind, but decreasing dewpoints on that north wind means temperatures will drop to near or just above freezing tonight. The clouds will keep the mercury from rising much Monday with highs very near what they were today, but just a bit less wind.

Sunday afternoon visible satellite imagery shows the Mid-South locked under widespread cloud cover. The clouds will persist through Monday at least. (College of DuPage)

The cloud party should break up Monday night as high pressure moves overhead with calm conditions and lows near 30.

Tuesday - Wednesday sun

For now, we believe abundant sunshine is ahead on Tuesday with highs back into the upper 40s. The NAM model, which is typically-more-aggressive with low clouds, thinks otherwise, but I feel optimistic.

Despite some high clouds moving over on Wednesday, south wind should finally being our temperatures back above normal. Morning lows in the upper 30s will rise to the mid 50s Wednesday afternoon and conditions remain dry.

Thursday rain - Friday dry

Thursday appears to be our next wet day as a weak system moves by in fast westerly flow at the jetstream level. It will be above normal temperature-wise though with lows in the 40s and highs in the upper 50s. Rain should not be heavy on Thursday. Thursday night into Friday looks dry and mild as we sit between systems, keeping a wary eye to the west. A few showers may arrive Friday evening, but not before highs climb above 60 degrees on south wind.

Weekend pattern shift

The "wary eye" mentioned above is because we'll be seeing an Arctic airmass drop into the Plains late this week that pushes into the Mid-South on Saturday. Timing of that cold air arrival is still TBD, but for now, we project a fairly wet day Saturday with a chance of thunderstorms due to the strength of the front moving in and a fair amount of wind. Temperatures will drop precipitously behind the front, potentially during the day Saturday, but very likely by Saturday night.

The Sunday morning GFS model forecast of surface features and precipitation from this Thursday night through next Sunday shows next Saturday's storm system moving through with rain and a potential for some light snow. At this point, various models disagree on the timing of cold air and moisture departure, and thus snow chances. The nature of the system though doesn't lend itself to more than light snow, if anything. (WeatherModels)

Will all the precipitation be gone before the cold air arrives? Model solutions vary on that as well. We'll be monitoring. Needless to say, behind that front, a bitterly cold airmass arrives, sending temperatures well below freezing by Sunday morning. Even with sunshine on Sunday, we may not reach the freezing mark for highs! That will be some 20-30 degrees colder than Saturday.

The European Model ensemble system predicts about a 25% chance that Memphis will get above freezing next Sunday, based on 50 runs of the European model this morning. (WeatherBell)

Winter arrives!

The long-range outlook indicates that next Sunday is the beginning of an overall pattern shift that brings in a run of below normal temperatures, perhaps continuing into early February. It's a pattern that will make precipitation forecasting somewhat tricky with each front/low pressure system that affects the area after that. Winter is NOT over snow-lovers! Do not give up hope just yet!

The NOAA temperature outlook for the end of January and first week of February indicates more cold air is likely on the way for the eastern half of the U.S. Stay tuned!

As always, look to the web or our MWN mobile app for the latest forecast information and to our social media platforms for the most up-to-date current trends. All links are below.

Erik Proseus
MWN Meteorologist

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