Sunday, March 17, 2019

A whole lot of sunshine this week with a mid-week shower possible

After what has seemed like a dreary couple of weeks, we will finally experience some pleasant, Spring-like weather this week. While we can't promise to stay dry the entire week, we should only see rain on one/two day(s), which that is still even semi-questionable. All in all, I hope you were able to find your sunglasses over the weekend because you will need to keep them around this week!


In terms of our temperatures this week, and how this compares to "normal", we will actually be a few degrees below normal to start the week and finish off the week a few degrees above normal. "Normal" for mid-March is right around the mid-60s, which we should hang around near 60 the first half of the week before reaching into the upper 60s to near 70 by this weekend. All in all, temps in the 60s sounds pretty nice to me.


Tonight and tomorrow

We have had a beautiful day today and this will continue into the evening and overnight hours. For this evening, temps will slowly begin to fall back into the 50s under a mostly clear sky. Overnight, we could begin to see a few more clouds fill our skies with temps dipping down to near 39.

Tomorrow, expect for a few of these overnight clouds to hang around throughout the day, leaving partly cloudy skies behind. While a few clouds will fill the sky, there will be plenty of sunshine to help temps to rise up to 59 for our high. 

Tuesday

Besides a few more clouds, Tuesday appears to be a near copy to Monday. While some clouds will fill the sky, there will be ample sunshine to make it feel pretty nice outside. Highs will reach near 50.

Wednesday and Thursday

By the middle of the week, we will begin to see a slight increase in cloudiness, with a chance of showers. A very weak "cold" front is expected to move through the area, bringing enough energy to maybe bring a few showers with it. Some models, like the GFS, want to bring showers through the area sometime on Wednesday, while the Euro wants to hold these showers until the AM hours on Thursday.
The GFS shows showers moving through the Mid-South during the afternoon to evening hours on Wednesday. (Tropical Tidbits)
Regardless of the timing differences, it does look like we may get a few showers sometime between Wednesday and Thursday. Highs both days look to be in the low to mid 60s. By Thursday afternoon, any shower chances should have moved along, leaving partly cloudy conditions for our afternoon and evening hours.

Friday and a glance at this weekend

We will begin to get a taste of warmer temperatures by Friday heading into the weekend. High pressure will build back into the Mid-South following Wednesday/Thursday's weak frontal passage. This high pressure will help to keep showers out and sunshine in.

The Weather Prediction Center's surface front forecast shows high pressure extending across much of the Eastern half of the U.S., including the Mid-South region (NOAA/WPC)
Highs will reach into the upper 60s to near 70 this upcoming weekend, with overnight lows falling to the mid 40s. With sunshine and just above average temps, I don't think we could ask for a more pleasant weekend. 

If you have plans for this upcoming weekend Friday and Saturday look like the "better" days to do so. While it is still a week away, models are hinting at some showers next Sunday. Worth mentioning if you are weighing doing something outdoors Saturday vs. Sunday, in which case I would make plans for Saturday rather than Sunday. As the week progresses, we'll keep an eye on Sunday's shower and thunderstorm chances. 


Caroline MacDonald
MWN Meteorologist

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

Friday, March 15, 2019

February 2019 Climate Data for Memphis, TN

February Climate Recap

February was dominated by warm air to start the month with multiple days of well above normal temperatures, including record tying temperatures on the 6th. A Strong cold front brought thunderstorms and much colder air for a couple of days before warm and wet conditions continued through mid-month. Below average temperatures followed a mid-month cold front that lasted for a week. Wet and cold conditions dominated the third week of the month with periods of thunderstorms and heavy rain, including precipitation on 7 of 8 days totaling over 5" at the airport. It warmed back up for the last week of the month with dry conditions. Overall, temperatures and precipitation were both well above normal for the month. There was no snowfall during the month.

The February temperature anomalies (departure from average) for the CONUS shows very warm conditions occurred in the eastern half of the country and cold air dominated the west, in particular the northwest. (Weathermodels.com)

As far as severe weather, many Flash Flood Warnings were issued over the course of the month, but the most active weather days were the 22nd and 23rd when Severe Thunderstorm and Flash Flood Warnings were issued in the metro. No damage was observed from storms, but there were several flood reports. Tornado Warnings, and a couple of tornado reports, occurred on the 23rd east of the metro closer to the Tennessee River.

Memphis International Airport, Memphis, TN


Temperature
Average temperature: 48.8 degrees (3.3 degrees above average)
Average high temperature: 57.9 degrees (3.2 degrees above average)
Average low temperature: 39.7 degrees (3.4 degrees above average)
Warmest temperature: 73 degrees (6th, 23rd)
Coolest temperature: 23 degrees (8th)
Heating Degrees Days: 449 (99 below average)
Cooling Degree Days: 3 (1 above average)
Records set or tied: February 6 (62 degrees, record high minimum tied; 73 degrees, record high tied)
Comments: Six days dropped to or below freezing this month, 3.5 below average

Precipitation
Monthly total: 8.78" (4.39" above average)
Days with measurable precipitation: 15 (5.8 days above average)
Wettest 24-hour period: 2.04" (11th)
Snowfall: 0.0" (1.3" below average)
Records set or tied: None
Comments: Seven days recorded more than 0.5" of rain, three of which were over 1".

Miscellaneous
Peak wind: South/47 mph (14th)
Average wind: 9.0 mph
Average relative humidity: 74%
Average sky cover: 80%

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

Cirrus Weather Solutions / MemphisWeather.net, Bartlett, TN


Temperature
Average temperature: 48.0 degrees
Average high temperature: 57.5 degrees
Average low temperature: 38.1 degrees
Warmest temperature: 73.6 degrees (3rd)
Coolest temperature: 22.7  degrees (8th)
Comments: None

Precipitation
Monthly total: 10.05" (automated rain gauge), 11.52" (manual CoCoRaHS rain gauge)
Days with measurable precipitation: 18
Wettest date: 1.76" (6th) (via automated gauge)
Snowfall: None
Comments: Five days recorded more than an inch of rain.

Miscellaneous
Peak wind: South/32 mph (14th)
Average relative humidity: 80%
Average barometric pressure: 30.12 in. Hg

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

MWN Forecast Accuracy

MWN average temperature error: 2.93 degrees
MWN forecast temperatures within 2 degrees of actual: 53%
MWN average dewpoint error: 2.90 degrees
MWN forecast dewpoints within 2 degrees of actual: 48%

MWN's forecasts extend out five periods (2.5 days, or roughly 60 hours). Historical accuracy statistics can be found here.

Climate Outlook - March

The March climate outlook for the United State from the Climate Prediction Center is shown below. Temperatures are forecast to be below normal for much of the northern, central and western U.S. For Memphis, odds favor slightly below normal temperatures, with a 30% chance of above normal temperatures, a 33% chance of near normal temperatures, and a 37% chance of below normal temperatures. Memphis typically averages 54.0° degrees for the month of March.


A wet March is forecast for the southwestern and southeastern U.S. with near normal precipitation across the northern tier of the nation. For Memphis, odds favor wet conditions with a 46% chance of above normal precipitation, a 33% chance of near normal precipitation and only a 21% chance of below average precipitation. March historically averages 5.16" of precipitation, including 0.4" of snow.


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

Tuesday, March 12, 2019

Dreary for now; windy conditions tomorrow with severe t'storms possible

After a few days of sunny skies, our dreary conditions have returned once again. Luckily, after some showers tomorrow and Thursday, we should remain dry for a while. Additionally, temperatures are expected to remain near to above average for the next few days.

If you are wanting to know Memphis' weather for the next few days without a nerdy tidbit, go ahead and skip forward to the "today" section. If you want a nerdy tidbit here you go. We are expecting showers and thunderstorms beginning late tomorrow afternoon and continuing through midday Thursday. While this may seem like a normal Springtime system for us, it is actually quite the opposite for some people. The system that will be bringing us showers and thunderstorms is associated with a low pressure system currently in Colorado, drifting towards the Central U.S. Over the next 24 to 48 hours, this system will go from around 1000 mb (pretty typical for a low pressure system) to around 976 mb (not typical for a mid-latitude low pressure system; i.e. this is as low as some land-falling hurricanes, crazy right?!). 

The Weather Prediction Center's Forecast for Wednesday shows a complex system moving across the Central U.S. This system will bring lots of snow to portions of the Western U.S. and Northern Plains while bringing rain across the Ohio River Valley and to us here in the Mid-South. (NOAA/WPC)
While this system will bring us some showers and thunderstorms, many in the Western to Central U.S. will experience blizzard conditions from this system. Additionally, this low pressure being so strong will help to drive some of the windy conditions we will see tomorrow and Thursday.


Today

We've already seen a few showers pass by bringing about a quarter of an inch of rain to the airport so far. Unfortunately, today just looks to be another one of those dreary types of day. While we aren't expecting any widespread showers, scattered showers will continue to pass by throughout the day.


Highs will reach to near 63. I would expect most of us to stay dry this afternoon and evening, but a stray shower or two cannot be ruled out. As for this evening into the overnight hours, clouds will continue to hang around the region. Overnight lows will drop to 56.

Wednesday & Thursday

The first half of Wednesday will be warm and windy. Highs are expected to reach near 75 (yes 75!!) with pretty windy conditions. Sustained southerly winds around 25 mph with gusts upwards of 35 to 40 mph can be expected. If you have any lose items that easily get blown around, I would go ahead and tie them down/bring them inside. These windy conditions will continue throughout the day Wednesday into Thursday.


By the late afternoon to early evening hours on Wednesday, showers with a few thunderstorms will begin to move through the area. Both the GFS and Euro model show the heaviest showers and thunderstorms passing through our area sometime in the evening, between 6 PM and midnight. 

GFS shows showers beginning in the late afternoon hours and continuing throughout the overnight hours into the early morning hours on Thursday. The heaviest showers appear to pass by before midnight. (Tropical Tidbits)
A few strong to severe thunderstorms will be possible as the main line of showers/storms moves through Wednesday evening. Damaging winds are the primary concern but a tornado or two cannot be ruled out.

SPC highlights the Mid-South in the Marginal Risk (1 out of 5) category. Damaging winds and an isolated tornado are the primary concerns. (NOAA/SPC)
In addition to severe storms, heavy rainfall is possible as these lines of storms move through. Since our ground is still pretty wet from all of the previous rain we have seen, it will not take a lot of additional rainfall to get some ponding in low lying areas.

The Weather Prediction Center includes much of our area in a Slight Risk for excessive rainfall/flash flooding. (NOAA/WPC)
While the majority of heavy showers will move through during the overnight hours, the cold front associated with these showers and thunderstorms is not expected to push through the Mid-South until the morning to mid-day hours on Thursday. For this reason, scattered shower chances will remain in place. Additionally, a few of these thunderstorms could become strong to severe, with damaging winds and an isolated tornado once again being the primary concern.

SPC once again highlights the Mid-South with a Marginal Risk (1 out of 5) for severe weather. Damaging winds and an isolated tornado are the primary concerns. (NOAA/SPC)
By Thursday afternoon, showers and thunderstorms are expected to push out of our area, leaving behind some more cloudiness. As the afternoon progresses, we may get a peak or two of sunshine. Highs are expected to reach into the low 70s.

Really the big story for Thursday, during and once showers pass through, will be our winds. Sustained southwesterly winds of around 20 mph with gusts upwards of 30 mph can be expected.

When all is said and done, our area could see anywhere from 2 to 3 inches of rainfall, with locally higher amounts possible.

Extending now through Friday morning, most of the Mid-South could see anywhere from an inch up to three inches of rainfall. Most of the Memphis metro region could see between 2 and 3 inches. (Pivotal Weather)

Friday and this weekend

We have not had a rain-free weekend since February 2nd & 3rd, meaning we have seen 6 straight weekends with some type of precipitation. This is finally set to change this weekend as we are expecting our first dry weekend in a while.


So what is allowing this dry weekend you may ask? Well, a high pressure system is expected to move into the Central and Eastern portions of the U.S. following Thursday's cold front system. 

The Weather Prediction Center's Medium Range Forecast for this upcoming weekend shows several high pressure systems across the Central and Eastern half of the U.S., including high pressure over the Mid-South region. (NOAA/WPC)
What does this high pressure mean for us? This will help to keep away any cold fronts that could bring precipitation into our area, meaning we are not expecting any type of shower activity this weekend. Beginning Friday and continuing throughout the weekend, skies will remain partly cloudy to mostly sunny. Additionally, highs will remain in the 50s, making for some pretty nice Spring-like weather. 

Glance at next week

Prepare for more spring like weather folks, as next week is shaping up to be a pretty pleasant week. With high pressure systems expected to remain over the Mid-South, conditions should remain sunny and dry throughout the majority of next week. 

The Climate Prediction Center's 6-10 outlook for next week, extending Sunday through Thursday, expects below average precipitation, meaning dry conditions will remain in place throughout the Mid-South. (Pivotal Weather)
In addition to this sunshine, highs will remain in the upper 50s to lower 60s, leaving us right around average to just a hair below average for mid-March. All in all, next week looks pretty pleasant if you ask me, just don't forget to keep the sunglasses handy. 


Caroline MacDonald
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

Thursday, March 7, 2019

Spring-like weather returns; severe t'storms possible Saturday

UPDATED POST -- 3/8/19, 2:15pm

Our severe weather risk for Saturday has increased and is now in the Enhanced Risk zone (level 3/5).


What to expect

Thunderstorms are expected in the morning. After an early afternoon lull, additional scattered storms are possible, but will not be as widespread. Some people may get no rain in the afternoon, while others could see a strong to severe storm. The chance of severe weather is fairly low in the morning and moderate to high in the afternoon, even though more people will see rain in the morning. All storms should be east of the metro by about 6pm as a front passes through.

The severity of afternoon storms will depend primarily on the amount of "recovery" the atmosphere is able to do after morning rain. Sunshine and dry weather aids in increasing instability - the severe weather ingredient in question. If temperatures soar into the mid 70s with dewpoints in the mid 60s, severe weather chances increase. Wind energy is less in doubt and capable of supporting severe storms should they have the storm "fuel" of instability to get them going.

Morning (about 9am-noon)
Storm chance: 90%
Severe weather chance: Slight
Threats: Large hail, damaging wind

Afternoon (about 2pm-6pm)
Storm chance: 40%
Severe weather chance: Enhanced
Threats: Large hail, damaging wind, a few tornadoes

Note also that it will be very windy tomorrow, even outside of storms in the afternoon. Expect southerly wind gusts as high as 40 mph or so.


ORIGINAL POST -- 3/7/19, 6:30pm

We have finally said goodbye to old man winter, at least for the foreseeable future. Temps are not expected to get near freezing over the next week, so get ready for some semi-spring like weather!

Unfortunately after a mainly dry (much-needed!) week, we will begin to transition back into a wet period starting late tonight. Showers are expected tomorrow with continuing showers and thunderstorms on Saturday. Keep the umbrella handy over the next few days!

Tonight and tomorrow

Clouds will continue to increase for the remainder of the evening, ahead of showers arriving later tonight. Temps currently sit around 50, and will only drop a few degrees overnight. Light rain is expected to develop around midnight with scattered showers continuing through the morning hours.

The high-resolution HRRR model simulated radar through midnight Friday night shows scattered showers remaining prevalent across the area for a good part of the next 30 hours or so. (WeatherModels.com)
The high-resolution HRRR model (shown above) shows scattered showers expected to continue through the afternoon and into tomorrow evening. Highs tomorrow will reach near 60. Other model data indicates the potential for a brief lull late tomorrow afternoon into the early evening hours, however, before more rain arrives early Saturday morning.

Saturday

I will start Saturday's discussion with this: 
We will need to keep an eye on things on Saturday. As previously mentioned, rain in the morning could be a good thing. If the rain breaks and we get some sunshine, that could become problematic. If we get any sunshine, that could increase the instability over our area. If we get enough instability, some afternoon thunderstorms could become severe. Without this instability, storms may remain sub-severe.

Regardless, the main concerns with any severe thunderstorms are damaging winds, although a tornado cannot be completely ruled out. Additionally, heavy rainfall at times could lead to some ponding on roadways. No major effects are expected on area rivers, streams, or lakes above what is already still elevated from the recent crest of the Mississippi River.

The GFS model has scattered showers hanging around through Saturday AM hours, with heavier showers and storms in the afternoon to early evening hours. (TropicalTidbits)

We will continue to monitor this threat over the next couple days. If you have plans Saturday, be sure to keep a close eye on the weather as the day progresses, particularly in the afternoon and early evening hours. We're hopeful that the storms will move out in time for start of the Memphis 901 FC soccer match Saturday evening, but it could be close!

Sunday

No rain. Highs in the the lower 60s. I'm not sure what more you could ask for for a weekend day! If you have any outdoor plans this weekend, Sunday will definitely be the day to take advantage of the gorgeous weather. 



Rest of next week

The majority of next week will consist if a semi-normal spring weather pattern. Monday and Tuesday temps will remain right around average for the time of year, with highs in the upper 50s to 60s. There is a chance of showers both days, we aren't expecting any widespread showers.

By the middle of next week, another cold front is expected to push through the area, bringing even more rain along with it. This is almost off in la-la land, so we will just leave it at that.

The Weather Prediction Center's Day 6 and 7 outlook (Tuesday/Wednesday) shows lots of precipitation over the Mid-South. (NOAA/WPC)

Caroline MacDonald
MWN Meteorologist

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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

Wednesday, February 27, 2019

UPDATE on winter weather chances and an Arctic blast

UPDATE (Fri., 3/1/19):

About 48 hours ago, the blog below was written, indicating the potential for some winter weather on Sunday afternoon, followed by a cold snap that would rival some we see in the middle of winter. This serves as a short update to that info (scroll down to the Sunday/next week sections below for the original post).

As of this afternoon, now less than 48 hours from the arrival of the Arctic cold front, little has changed from what I wrote below. We have a couple more models available that cover the time period in question, and the American GFS model continues to be the one that keeps precipitation around the longest versus the European model and now the high-resolution North American model.

However, we are narrowing in on what I believe to be the likely solution, and snow-lovers won't like it. We will indeed see a scenario where cold air "chases out" the precipitation, meaning that the only way to get snow will be where the cold air catches up with lingering precipitation. That is most likely to occur north of the metro. By Sunday mid-afternoon, as temperatures are dropping into the 30s, rainfall will be departing to the east.

If we get any flakes in the metro (possible), we will still be above freezing and they will melt. It is not expected to drop below freezing until the evening hours when precip is gone. The NWS "reasonable worst case" forecast for snow on Sunday is below. It depicts the scenario that has less than a 10% chance of occurring. That forecast says 1-2" of snow is the worst case (or best case, right teachers??) for Tipton County and points north. Even the unlikeliest of scenarios still produces less than an inch in the metro. In other words, it ain't happenin'! (Don't you hate our no-hype approach?)


As for the cold air... well, that IS happenin'! Next week will feel more like January than March. Plan on more hours below freezing than above from overnight Sunday night through mid-day Wednesday! Overnight lows will be closer to 20° than 30° Monday through Wednesday mornings and we may not rise much above freezing Monday afternoon at all. Couple that with a brisk north wind and the Arctic blast will feel like single digits Monday at the bus stop! Plan now to protect any outdoor vegetation that you want to keep starting Sunday night and lasting a few days. Expect the temperatures to recover pretty quickly though by Thursday and Friday (as precipitation chances return, of course).

Sorry for the bad news, but I'm ready for spring, so let's get this out of the way and get ready for some spring thunderstorms and rainbows!


ORIGINAL POST (Wed., 2/27/19)

The past few days have been an opportunity to dry out, and while we end the week with rain chances, they are fairly low, and rainfall should remain fairly light. That will provide more time for the ground to dry out a bit and local streams, creeks and rivers to return to their normal streamflow - unless they lead directly into the Mississippi River! With the river nearing 40 feet on the Memphis gauge, portions of the Wolf and Loosahatchie River and Nonconnah Creek will still remain high as water backs up from the main stem.

A hydrograph showing recent and forecast river levels at the Memphis gauge on the Mississippi indicates a "flat crest" approaching next week with levels near 41' for several days before dropping by mid-March. Today's reading is about 39.5'. (NWS)


Thursday and Friday

A cool front is moving south across the Mid-South this afternoon and will bring an end to the mid 60s we've had today as it drops into north MS. There will be low rain chances this evening, but rain will remain light and many residents of the area will see nothing at all. With the front stalled in the region, we can expect more cloud cover the next couple of days, small rain chances Thursday morning and again Friday into Friday night, and cooler, but not cold, temperatures. Look for the mercury to remain in the 40s most of Thursday, then mid 30s Thursday night and lower to mid 50s Friday.

The National Forecast Chart shows rain chances in the area Friday as a front sits to our south. Notice that mixed precipitation or snow is not too far to our north as cold air is poised to move south by Sunday. (NWS)

Saturday

Models have had a hard time with the weekend forecast as Arctic air spills south towards the area and low pressure forms to our west and moves across the region. As of now, it appears Saturday may not be bad with most rain holding off until Saturday night and mild temperatures that once again climb back into the 50s to near 60. If you have stuff to get done outdoors, this is your day to do it!

Saturday night is when the Arctic front starts dropping into the area as low pressure moves along the existing front draped over the region. Rain is basically a certainty Saturday night with temperatures in the 40s.

Sunday

Sunday could get interesting. The speed with which the precipitation moves out Sunday, along with the surge of cold air moving into the region presents somewhat of a dilemma. Sunday morning will likely be wet, but the colder air will be plunging south on a brisk north wind. While the European model has been quick to push the precipitation out, providing for a dry afternoon, the American GFS model hangs some precipitation back in the afternoon and is a little faster with the cold air. It changes rain over to light freezing rain, sleet or snow Sunday afternoon as temperatures drop below freezing after a morning high in the 40s. The wind will also be brisk, meaning wind chills drop below freezing probably by noon and make it into the teens by evening. The GFS also is dry Sunday night though like it's fancy European cousin.

The GFS model for Sunday afternoon projects a wintry mix of precipitation as temperatures plummet behind an Arctic cold front. The European model (not shown) is dry by Sunday afternoon. (WxBell)

If the GFS is right, we could see a light coating of freezing rain or a dusting to light accumulation of snow. We'll need to monitor this situation carefully, as we're still 4 days out, but it's worth mentioning. Right now, I don't expect we'll see enough to have to worry about travel Sunday night into Monday. My gut tells me that this "cold air chasing precipitation away" scenario won't yield much if anything. But I've also always said, "winter isn't over until we get past the first weekend in March!" It appears this year, it might come in like a lion!



Next week

Unfortunately, this isn't a quick punch of cold air and right back to spring warmth. I fear for the blooming flora across the region as a bitter airmass sinks into the region Sunday night through at least the middle of the week. We'll easily see lows in the lower half of the 20s to start next week, perhaps for 3-4 nights, and a few mornings could see outlying areas in the teens. High temperatures may not get out of the 30s  Monday-Wednesday! Hopefully this will mark the end of winter, but the long-range outlooks suggest cooler than normal temperatures (but not necessarily that cold!) stick around into the middle of March. Plan ahead for any precautions you'll need to take against a hard freeze for anything that is popping up out of the ground or blooming!

NWS forecast model temperatures for the upcoming 10 days. (WeatherModels.com)

I may try and get a blog update done on Friday for more clarity on the weekend, but will be out of town Saturday as I represent StormWatch+ at Tennessee Severe Weather Awareness Day in Nashville. We've already had an early taste of severe weather season last Saturday. Despite the cold, it's also time to be giving some thought to severe weather preparation plans for this spring. This week is Severe Weather Awareness Week in Tennessee and Arkansas, while Mississippi had theirs last week.

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

Friday, February 22, 2019

Overnight storms, then severe storms -- but the end is in sight!

The drumbeat of raindrops falling is incessant... and we're not quite done. In fact, the next 24 hours or so pose more risk than we've seen in a few months, both in terms of the flash flooding potential and the severe weather risk. Let's start with the water, then move onto the storms.

Rest of today and tonight

Continuous rain today, though perhaps not as heavy as what we've seen recently, is keeping things saturated. Metro areas in west TN and east AR have seen 1/3 - 1/2" of rain since sunrise this morning (as of 2pm) while northwest MS is likely pushing an inch. The heaviest rain since yesterday has been southeast of the metro where Flash Flood Warnings are in effect. Today's rain is on top of 5-7" the metro has seen in the past 2 weeks, as shown below.

14-day precipitation totals (since Feb. 8) show 5-7" of rain has fallen through early this morning. (NOAA via WeatherBell)

Steady rain is likely to continue this afternoon and perhaps into the evening, though high-res models disagree a bit on a potential break in the rain for the early evening hours. However, once we get into the nighttime, after about 10pm, a warm front to our south will lift north and cross the metro overnight, pushed by an increasingly strong southerly low-level jet stream a couple thousand feet up. That will result in periods of thunderstorms overnight, perhaps lasting much of the night.

The high-res HRRR model future radar product through 7am Saturday shows the overnight storms lifting north through the metro ahead of a warm front. (WeatherModels.com)

Rainfall will be heavy enough in these storms to be classified as "frog-stranglers" and "gully-washers," dropping up to 2-3" overnight, perhaps higher in spots. Flash flooding becomes a much more concerning trend as the night goes on, so if you will be out overnight, be extremely cautious! Creeks and streams could overflow, rivers are already high, and low-lying or poor drainage areas in the urban jungle could see accumulating water. If you live near a creek or stream or other area that floods in very heavy rain, be aware that could happen overnight. The NWS Weather Prediction Center has the metro straddling the line between a moderate and high risk of rainfall that exceeds levels required for flooding, or about a 50% chance within 25 miles of you. North MS has already seen some water rescues in the past 24 hours - flooding is a threat to be taken seriously, particularly south of the state line!

The Memphis metro is in a Moderate (level 3/4) threat area for flooding through tonight, while north MS is in a High risk (level 4/4). This means there is about a 50/50 chance of having  rainfall exceed flash flood criteria within 25 miles of you. (NOAA/WPC) 

As far as storm threats, we're not necessarily expecting them to be severe. The Storm Prediction Center has our area on the edge of a Marginal Risk (level 1/5) for severe weather, with the possibility that a few storms could have some hail. Damaging wind and tornadoes are not currently expected overnight, but that doesn't mean the storms won't make a racket! If you had issues with storm noise Tuesday night, expect it again tonight (and it may last longer). Also know that due to the frequent lightning, power outages will also be possible.

SPC has the metro outlooked in a Marginal Risk (level 1/5) for severe storms overnight. The main threat is a few hail storms, but even that threat is very low. Storms will produce plenty of lightning and thunder though! (NOAA/SPC)

Saturday

Once the warm front moves to our north, we should catch a bit of a break for a while Saturday morning. By about sunrise, the storms will be to our north and a humid, very warm, and increasingly unstable airmass will overtake the area. Temperatures in the morning will rise to near 70° with gusty south wind and hit and miss showers or a thunderstorm. The stage will be set for the potential for severe weather in the afternoon as a potent cold front cuts through an airmass characterized by strong, turning winds aloft (bulk shear over 50 kts and SRH near 200 for you weather nerds), sufficient instability (CAPE of 1000-1500), and plenty of available moisture at all levels (PWAT near 1.6").

Storms will likely form ahead of and along the front by late morning in AR and move our way by early afternoon. We are expecting a line of storms, with perhaps additional storms ahead of the line, during the afternoon hours Saturday, or roughly between 1-5pm. These storms will tap into the springtime atmosphere and have the potential to produce damaging wind gusts and a low threat for a couple tornadoes embedded within the line.

The HRRR model forecast radar simulation from noon to 6pm Saturday shows a broken line of storms moving through the metro, intensifying as they near the Mississippi River about 4pm. A few storms are also possible ahead of the line. (WeatherModels.com)

A second possible solution for Saturday, from the high-res NAM model looping from 10am-8pm Saturday, shows an earlier arrival of the storms, and perhaps a couple of lines between 1pm-4pm. It also depicts more organization of the storms as they move towards the metro. (WeatherModels.com)

Severe weather threats

While the threat of damaging wind will be much higher (right now pegged at about 30% within 25 miles of any point), a Tornado Watch is likely during the afternoon as tornado probabilities are currently forecast at about 10% within 25 miles of you. Consider now what your plans are for Saturday afternoon and be prepared to take shelter wherever you are, if necessary. In addition, with the excessively wet ground, storms that produce sub-severe wind gusts (40-50 mph) may be sufficient to uproot trees and cause power outages. A Wind Advisory has also been issued for non-convective wind gusts to 30-40 mph Saturday would could pose an additional threat to trees with shallow roots in saturated soil.


After the storms

By 6pm Saturday evening, the storms will likely be gone and evening plans should continue with little concern. Moving into Sunday and early next week, I am pleased to report that it will be DRY with plentiful sunshine and seasonal temperatures. A few mid to late week showers are possible, but there is currently no threat of heavy rain that would cause additional flooding concerns as high temperatures remain in the mid 50s to near 60.

Stay tuned to our social media channels for the latest updates and be sure you have the MWN app downloaded with StormWatch+ Alerts activated for your locations of interest. Links are presented below.

Erik Proseus
MWN Meteorologist

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