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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Follow MWN on Facebook and Twitter for routine updates and the latest info!
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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

Wednesday, February 20, 2019

Weather 102: Why is nighttime thunder so loud?

MWN friend Kristen Boyden asked a great question: "Why were Tuesday night's storms so loud?"

The overnight storms (and this is pretty common for nighttime storms and some during the day as well) were what we call "elevated thunderstorms." Basically, we had a very strong temperature inversion in place, in which the temperature rises with height rather than cooling. It was about 45° F at the surface during last night's storms, but 57° F at just 4,000 feet up! That inversion creates a stable layer in the atmosphere at the low levels and basically acts like a lid at 4,000 feet above us.

An atmospheric sounding (temperature/humidity profile) of the airmass over Memphis Tuesday night shows temperature (red line) increasing as you go up into the atmosphere, an inversion. That inversion "caps" the atmosphere below, trapping the sound of the thunder in the lowest few thousand feet. (NOAA/AMDAR)

When lightning discharges under that lid, the sound of the thunder is trapped close to the ground. Since the sound can't escape UP ↑, it bounces around between the ground and the stable layer above (the lid), amplifying the noise. It's like setting off firecrackers in grandma's pressure cooker!

Elevated thunderstorms occur when warm air overrides cooler air near the surface, creating a temperature inversion, and thus a stable layer of air in the low levels, above which convection occurs. (Graphic courtesy @wxbrad)
In addition, general daytime noise is reduced at night, so the thunder seems louder because the ambient noise level is quieter. (Like when your baby lets out a cry in the doctor's waiting room vs. in a house full of other kids!) I frequently say that thunder at night is often louder than during the day, but in fact, ELEVATED thunderstorms are truly the cause for the noise level. They just happen to occur more often at night! It doesn't mean they are "more severe" or even more damaging. They're just louder.

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

Rain returns Thursday, severe weather possible Saturday

Our rain has finally gone away, but unfortunately it won't stay that way for very long. Multiple rounds of showers are expected to return starting tomorrow, with some severe thunderstorms being possible on Saturday. Over the past day, most of the Mid-South has seen between 2 to 3 inches of rain.

Observed precipitation across the Mid-South shows much of the Memphis area receiving 2 to 3 inches of rainfall over the past day with some areas receiving even more. (NOAA/NWS)

Unfortunately, a lot more rain is expected from tomorrow through Saturday. We will not begin to transition away from this perpetual wet period until next week, but even then the ground will still be pretty soggy.

The Weather Prediction Center's precipitation forecast from now through Saturday evening shows additional rainfall of 2-3" is expected across the Mid-South. (Pivotal Weather)


Rest of today

Skies are expected to continue clearing out for the remainder of the day. While we won't completely clear out during the daytime, we could get a glimpse or two of some sunshine by this afternoon.

Currently visible satellite imagery shows a blanket of clouds to our East, with some clearing to our West. We should continue to see clearing skies this afternoon. (College of DuPage)

As for this evening into the overnight hours, skies will continue to clear leaving us with a mostly clear sky overnight. Conditions will be favorable for some patchy fog to develop in outlying areas. Temps will dip back down to near 38 overnight so a bit of frost is possible on your car if you park outside overnight.

Thursday and Friday

The first half of tomorrow will actually be pretty nice. Clouds will remain, but we may get a peak or two of sunshine in the morning. By tomorrow afternoon, clouds will continue to increase ahead of our next rain maker with highs nearing 52. Scattered showers will arrive during the afternoon hours with even more showers expected in the evening and overnight hours. A thunderstorm or two is possible, but we are not expecting any severe thunderstorms with this round of precipitation. 

Friday appears to be a continuation of Thursday evening, with showers across the area. Once again, a thunderstorm or two is possible during the day, but we are not expecting any severe thunderstorms. Highs will reach near 58. Showers and a few thunderstorms will likely hang around into and through the evening hours on Friday as well. 

The GFS model shows rain remaining across the Mid-South through much of Thursday evening and Friday. (Tropical Tidbits)
*Note: a Flash Flood Watch has been issued for much of the Mid-South in anticipation of this additional rainfall. This watch is set to begin tomorrow (Thursday) at noon and continue through Saturday night. Stay safe over the next few days folks. If you come across a flooded roadway, turn around, don't drown.*

Latest hazards map outlines Flash Flood Watches in green with Flood Warnings in the hatched lime green.

Saturday

While it is still a few days away, we will need to keep an eye on things on Saturday. Showers and thunderstorms are expected through the day on Saturday, but severe thunderstorms appear to be possible for the afternoon hours (timing will become more refined as we get closer). A combination of highs reaching into the low 70s (yuck), along with plenty of moisture (dewpoints in the "muggy" category), strong wind fields aloft, and the arrival of a potent cold front leads to this severe weather potential. 

The Storm Prediction Center currently has the Mid-South at a 15% chance of seeing severe weather within 25 miles of you on Saturday, equivalent to a "Slight Risk" (or level 2/5) if this were within the first 3 days of the forecast. (NOAA/SPC)
The main concerns with this system are damaging winds, but there is a low-end tornado threat as well. Additionally, since we have seen so much rain already this week, any more rain we see (especially heavy downpours), could become problematic over some areas. Also, due to very saturated ground, wind gusts could uproot trees at a lower speed than would typically be required. Like I mentioned before, we are still a few days away with lots of details and logistics to be figured out. It is worth mentioning and definitely worth keeping an eye on. 

Sunday into next week

We will finally get a small break from all of this rainfall next week. Sunday and Monday look to be clear with the possibility of a shower or two by midweek. Temps will remain right around average, leaving next week looking pleasant to "normal". For those wondering when/if winter will come back, it looks like temperatures may return to below average by the following weekend, but that's getting a bit into la-la-land forecast.



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

Sunday, February 17, 2019

[MWN VIDEO BLOG] Where are those ark plans? Flooding rain possible over the next week

I know we're tired of the rain, but another very wet week is ahead. The potential for flooding and flash flooding exists with heavy rainfall Tuesday into Wednesday and again Saturday into Sunday (next weekend), though rain chances occur nearly every day this week, except Monday. Watch the video forecast discussion below for all of the details or check out the graphics below for a high-level overview.



Unable to view the video? Try clicking here: https://youtu.be/jjTosUgi9-Y

Rainfall over the past week, laying the groundwork for possible flooding this week by saturating the ground across the region. (NOAA/NCEP via Pivotal Wx)

The GFS model shows repeated surges of atmospheric moisture (shown as precipitable water) over the southeastern U.S. over the coming week. (PivotalWx)

Total precipitation forecast through next Sunday from NOAA's Weather Prediction Center. 4-7" of rainfall is projected in the Memphis area with 10"+ in the TN Valley. (NOAA/WPC via PivotalWx)


Stay with us all week for the latest on the heavy rain and potential for flooding, as well as forecast updates as we tweak the timing and amounts of rainfall with each system as it approaches. Links to where to get all this information can be found below, and certainly be sure to download the MemphisWeather.net app for all of it in one neat little package, including StormWatch+ Alerts for flood and flash flood alerts for your location.  Stay dry (as best you can!) and stay safe!

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

Monday, February 11, 2019

January 2019 Climate Data for Memphis, TN

January Climate Recap


Despite some (fairly typical) large swings during January, overall the average temperature for the month ended just a bit above normal. The month started warm with consecutive days in the 60s at the end of week 1, but a cold front brought them back to near average through mid-month. The second half of the month featured more swings from cold to mild with various frontal passages. However, despite the swings, no records were broken with highs mostly in the 40s and 50s and lows in the 20s to 30s. The largest contributor to the above normal average were overnight lows that were about 1.5 degrees above normal, while daytime highs were very close to average for the month.

Precipitation to start 2019 was also a bit above normal, about three-fourths of an inch above the long-term average of nearly 4". Despite having eleven "rain days," most precipitation that contributed to the total fell on just four days that totaled more than one-half inch. Snow fell on the 19th (a dusting that officially was recorded as 0.2") and traces on the 25th and 26th. Overall, a disappointing month for snow-lovers in general! As far as severe weather, three Severe Thunderstorm Warnings were issued for the southern metro as a line of storms swept through early in the morning on the 19th. No damage was reported. On the 23rd, strong southerly (non-thunderstorm) wind downed a large tree in Southaven.


Memphis International Airport, Memphis, TN


Temperature
Average temperature: 41.8 degrees (0.6 degrees above average)
Average high temperature: 49.7 degrees (0.2 degrees below average)
Average low temperature: 34.0 degrees (1.4 degrees above average)
Warmest temperature: 68 degrees (8th)
Coolest temperature: 20 degrees (31st)
Heating Degrees Days: 712 (26 below average)
Cooling Degree Days: 0 (1 below average)
Records set or tied: None
Comments: 14 days dropped to or below freezing this month, essentially right at average.

Precipitation
Monthly total: 4.75" (0.77" above average)
Days with measurable precipitation: 11 (1.5 days above average)
Wettest 24-hour period: 1.29" (23rd)
Snowfall: 0.2" (1.7" below average)
Records set or tied: None
Comments: Four days recorded more than 0.5" of rain, two of which were over 1".

Miscellaneous
Peak wind: West/50 mph (19th)
Average wind: 8.7 mph
Average relative humidity: 72%
Average sky cover: 60%

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

Cirrus Weather Solutions / MemphisWeather.net, Bartlett, TN


Temperature
Average temperature: 41.1 degrees
Average high temperature: 49.8 degrees
Average low temperature: 32.4 degrees
Warmest temperature: 69.4 degrees (8th)
Coolest temperature: 19.0 degrees (31st)
Comments: None

Precipitation
Monthly total: 4.74" (automated rain gauge), 5.40" (manual CoCoRaHS rain gauge)
Days with measurable precipitation: 13
Wettest date: 1.17" (23rd) (via automated gauge)
Snowfall: Trace
Comments: None

Miscellaneous
Peak wind: Northwest/30 mph (19th)
Average relative humidity: 78%
Average barometric pressure: 30.18 in. Hg

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

MWN Forecast Accuracy

MWN average temperature error: 2.52 degrees
MWN forecast temperatures within 2 degrees of actual: 60%
MWN average dewpoint error: 3.02 degrees
MWN forecast dewpoints within 2 degrees of actual: 53%

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

Climate Outlook - February

The February climate outlook for the United State from the Climate Prediction Center is shown below. Temperatures are forecast to be above normal for the deep south and below normal across much of the northern U.S. west of the Great Lakes. For Memphis, odds don't favor above or below normal temperatures, with a 33% chance of above normal temperatures, a 34% chance of near normal temperatures, and a 33% chance of below normal temperatures. Memphis typically averages 45.5° degrees for the month of February.

A wet February is forecast for much of the United States, particularly the east and Desert Southwest, while drier than average conditions are expected in the Pacific Northwest. For Memphis, odds favor wet conditions with a 53% chance of above normal precipitation, a 33% chance of near normal precipitation and only a 14% chance of below average precipitation. February historically averages 4.39" of precipitation and 1.3" of snow.

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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

Saturday, February 9, 2019

Late-winter rainfall could lead to minor flooding this week

Brrr has it been cold lately. After we had highs in the 70s earlier this week, temps have been in the 30s and 40s over the pasts few days. Luckily, our temperatures will continue to climb this weekend and into next week. The average high for mid-February is typically in the mid 50s, which right around where we will be next week. Until then, highs will remain in the upper 40s for the next few days, with lots of showers tomorrow and Monday. Go ahead and find your umbrella, you're going to need it.


Saturday

Some high clouds continue to stream overhead, but even the sunshine isn't helping out our temperatures that much today. We only expect to warm a few more degrees to near 43 this afternoon. Unfortunately, winds remain around 10 mph, making it feel cooler outside than the thermometer shows. 

Clouds will begin to increase in coverage this evening, before showers arrive late tonight. If you are heading out this evening, you shouldn't need the umbrella until after midnight. Although you will definitely want to keep the jacket around as temps will be in the 30s. 

Sunday and Monday

Rain ... and a lot of it. Sunday and Monday will be two very wet days folks.

GFS model loop from 6 PM Saturday (tonight) through early Tuesday morning shows showers hanging around the Mid-South throughout Sunday and Monday. (Tropical Tidbits)

On Sunday, showers are expected to begin early in the AM and continue throughout the majority of the day. While we could see a few breaks during the day, expect light rain to hang around. Temperatures will be in the 40s throughout the day, with highs nearing 48. Despite rain starting late Saturday night, perhaps with temperatures in the 30s, we have no concern for the potential of wintry weather.

For Monday, expect milder conditions with temperatures warming to near 60 for our high. Showers will remain light through the AM, but heavier rain and a few strong thunderstorms will be possible Monday afternoon into Monday evening.

The Storm Prediction Center's Day 3 Outlook, for Monday, has areas in northern Mississippi included in a Marginal Risk (level 1/5) for severe weather. This is still a couple days away, so this forecast could change a bit. (NOAA/SPC)
We will need to keep an eye on this severe weather threat over the next few days. While it looks like we could get a few strong storms, this does appear to be a low-end severe threat with damaging wind as the primary concern.

In addition to the severe weather threat, flooding could become an issue. From now until Tuesday, we are expected to see several inches of rain. Additionally, rainfall could be heavy at times, which could lead to some flooding in poorly drained areas. The heaviest rain is expected to run near and north of I-40.

The Weather Prediction Center's Day 1-3 rainfall forecast shows areas north of I-40 possibly receiving upwards of 3-4 inches of rainfall over the next few days. Locally higher amounts could be possible across the Mid-South. (NOAA/WPC)
Currently, there is a Flood Advisory for the Mississippi River (in Crittenden, DeSoto, and Shelby Counties) and a Flood Warning for the Loosahatchie River in northern Shelby County. Both rivers, as well as other local streams and tributaries, could see minor flooding due to all of the rain we are expected to see over the next few days. The Loosahatchie River would likely near this stage towards the beginning of next week, while the Mississippi River likely wouldn't reach this stage until later next week as rainfall upstream makes it way south. Regardless, if you come across a flooded roadway, do not attempt to cross it. Turn around, don't drown.

Over the next few days, it would be ideal to keep an umbrella handy and to stay weather aware Monday evening as severe weather is possible.

Tuesday through next week

After a wet couple of days, we will see a much needed break from the showers on Tuesday and Wednesday. Additionally, sunshine is expected to make a return, aiding in keeping our high temperatures near average in the mid 50s. Unfortunately, this break will likely be short lived as more showers could re-enter the forecast towards the end of next week.

The good news through all of this is that after our brutally cold weather recently, the cold looks to stay away for now and through next week. 

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
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

Wednesday, February 6, 2019

Spring, winter, spring... what season are we in again?

Wow, what a stretch of warmth! After suffering through winter's chill last week (but not nearly as badly as those in the Midwest did), the rush to spring was swift!

Last Thursday morning, our low wind chill was 10°.  By Saturday afternoon, the high was 70°, and we haven't looked back! That groundhog must've been on to something...



The string of 70-degree days has reached 5 days as of today and will likely reach 6 days tomorrow morning before things change, a lot. But before that front hits, we should tie the record for longest streak of 70° days in the month of February, and the 2nd earliest stretch of consecutive 70° days on record, bested only by Jan 3-8, 1880. Yes, 1880. None of us remember that.

Wednesday-Thursday morning: warm, windy and stormy

With a cold front sitting to our north, the metro sits in a "warm sector" (basically a February sauna) with scattered showers and thunderstorms fueled by warm moist air transported north from the Gulf on southerly wind.

Areas primarily north of I-40 are under a low-end risk of severe weather. I'm not overly concerned about it, but a few storms north of the metro could see a few strong wind gusts. There's also a very low, non-zero, risk of a tornado, but that is more likely closer to the front to our north as well.

Wednesday's severe weather outlook, from SPC
The risk of a few storms continues into the evening hours before they lift north of the metro as a warm front pulls north in response to the cold front approaching from the west. A few showers are possible overnight, but nothing strong or particularly wet (other than the humidity levels). The warmth continues into Thursday morning as the front moves across AR. Rain and a few thunderstorms are possible in the morning until the front arrives, which will bring an abrupt end to our 70 degree weather!

Severe weather outlook for Thursday, via SPC.
In addition to the muggy air in the morning, strong and gusty south wind will reach 30-40 mph. A Wind Advisory (a.k.a., "Skirt Alert") is in effect for counties bordering the Mississippi River and west into eastern AR.


Finally, bouts of heavy rain over the next 24 hours will likely result in 1-2" of precipitation in the metro. Not flooding rain by any means, but localized ponding could occur in and just after the heaviest downpours.

The Weather Prediction Center's precipitation forecast through Friday evening. (WxBell)

Thursday afternoon: FROPA

By early Thursday afternoon, the front swings through the metro (called "FROPA," or frontal passage, in your local weather discussion). You'll know when it does if you happen to be out. If you won't, you'll definitely know when you leave work or school later in the afternoon! Showers continue behind the front, but the warm air will be quickly pushed east. Temperatures will fall precipitously, likely reaching the 30s by evening (from near 70 at noon). Depending on your bent, fortunately or unfortunately, the rain looks to end before the "cold enough" air arrives, as is typical. No snow.


Friday-Saturday: Back to winter

We end the week with the only guaranteed dry days in the entire forecast period, and of course that is when the cold air is here as well. Wake-up wind chills Friday morning will be in the teens with temperatures in the 20s. Cool north wind continues Friday with a high of (maybe) 40.

Saturday sees more of the same with lows again in the 20s, chilly wind, and a slightly-moderated high temperature in the mid 40s.

Sunday into next week: Wet

As cold high pressure pushes off to our east, we once again get stuck in a wetter pattern with multiple low pressure systems moving across the larger Mid-South region, dropping buckets of rain.  This has been advertised for some time by the week 2 outlooks from the Climate Prediction Center. Below is today's outlook. It indicates above average probabilities of above average rainfall. I guess that means our area excels in precipitation. It does appear that cold air will be held at bay, so temperatures should be seasonal amongst all the rain.

The CPC precipitation outlook gives us a strong probability of above average precipitation well into the latter part of next week. (PivotalWx)
Keep up with the latest on our wacky weather pattern by following MWN on social media or downloading the MWN app for the latest forecast, radar, and severe weather alerts! Links are provided below.

Erik Proseus
MWN Meteorologist

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