Chilly Change this Weekend

What a change in just 24 hours time!  We set a new record high yesterday in several communities, including Nashville.

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Today, it feels like winter again with wind chills in spots in the 20s.  Outdoors now as of 7:50am, we have a mix of 30s and 40s.

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Wind chill now…

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While the rain has moved out, gusty wind has not.  Here are recent wind gusts.  It’ll remain gusty until late this afternoon.  In general it’ll be a northwest wind, 10-20 mph.

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At least it’s sunny & bright, in the wake of last night’s storms.

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Notice where the heaviest rain fell overnight (green shading = at least 0.5″)….and where we had reports of severe weather (where you see Hs and the Ws).

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SO….today, expect a mix of clouds and sunshine.  Temperatures late this afternoon will be in the 40s — several degrees below the average of 55.

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Highs across the rest of the area will look like this.

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As Canadian high pressure builds in tonight, it’ll turn even colder.  We’ll have a hard freeze by dawn on Sunday.

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Then, with increasing clouds Sunday afternoon it’ll be more seasonable, in the 50s.

Looking for something to do today?  The Nashville Predators are hosting a 5K Run/Walk downtown, called Nashville Predators Fangtastic 5K Run/Walk.  It gets underway at 10am.

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There’s a Preds home game this afternoon, against one of the best teams in the NHL — the Washington Capitals.

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You could also go to the Nashville Zoo and say hi to Mazi….a baby giraffe born just over a week ago!  Just remember to dress warmly!

Temperatures will continue their wild ups and downs this coming week.  I’ll tell you all about it, and talk about our next storm chance on Channel 4 News, between 8:30am and 9:30am.  Alan Frio and I hope you join us!

DT

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4WARN Weather Alert

A deceiving day! Mood boosting sunshine and dry conditions for every spot in Middle Tennessee. Here’s a peak outside our Downtown camera…

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As expected, Nashville breaks a temperature record today — currently at 80 degrees (2:36 PM).

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Last record of 77 degrees was set back in 1890. All time highest record in February was 84 degrees, set back in 1962 and we are not far from it!

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Breezy southerly winds ahead of an approaching cold front are partially responsible for this crazy warmth. If you’ve been outside at any point today,  you quickly realized it is not the day for the hat! Winds are cranking, with occasional gusts exceeding 30 mph.

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As the cold front continues pushing eastward, it will brings showers and strong to potentially severe thunderstorms with it.

Here’s the latest from the Storm Prediction Center:

‘Slight Risk’ (2 out of a 1 to 5 scale) has been expanded a bit further south, including a good chunk of areas east of I-65.daphne-severe-risk-region

Though the greatest impact will be damaging straight line winds, an isolated tornado and hail cannot be ruled out with this system. Areas east of I-65 will have the greatest threat of seeing some of these stronger storms blossom out.

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Here’s how Futurecast times things out…dd-rpm-4km-eveningdd-rpm-4km-evening2dd-rpm-4km-evening3dd-rpm-4km-evening4dd-rpm-4km-evening5

I’m in agreement! Bulk of the activity pushes out just after 1 AM on Saturday. After that? Much cooler air filters in behind the cold front on Saturday. You’ll see more sunshine but it will come at the cost of unseasonably chilly upper 40s during the day and sub-freezing Saturday night into early Sunday morning. Ouch! It is a temp shock.wsmv-4-plus-4-pm

I have the full storm timeline and what to expect as you plan your Friday evening on Channel . Movie and popcorn night might be your best bet!

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See you in a few!

-Meteorologist Daphne DeLoren

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February 24: Record Warmth, Severe Storms, Daily Links

WEATHER

Exceptionally warm and breezy weather today, with high temperatures in the upper 70s to around 80° and southerly winds gusting to 30 mph:
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Today’s record high is 77° set all the way back in 1890, and that record looks likely to fall.  If we do hit 80° in Nashville, it will be only the fourth 80°+ reading in the month of February since record-keeping began back in the 1870s.  (Thanks to loyal 4WARN commenter and fellow climate nerd Fred for doing the research on that particular bit of trivia!)  The all-time February record is 84° set on February 13, 1962…that looks to be safe, but we’ll give it a run!

A good chance of thunderstorms will sweep across the Midstate from west to east this evening and tonight — the HRRR model’s radar simulation shows a few showers ahead of the “main event,” but those won’t be anything more than a nuisance:
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Other forecast models show slightly different timing — smoothing out the differences between those models, here’s when you can expect the strongest storms (along with the odds of storms occurring in the first place):
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All of the available data shows the greatest severe threat shaping up along and east of I-65 after 8pm, but even with the main line of storms, this isn’t an off-the-charts threat.  The Storm Prediction Center’s short-range ensemble model (SREF) crunches the numbers and shows a 30-50% chance of storms with severe weather ingredients this evening, with the highest potential to the north of I-40 and east of I-65:
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The SPC has outlined a “Slight Risk” (level 2 of 5) for severe storms to the northeast of Nashville, with a “Marginal Risk” (level 1 of 5) for most of the rest of the Midstate:
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The greatest tornado potential will be to our north, in the “Enhanced Risk” area.  Damaging straight-line winds will be the main threat in our neck of the woods:
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Behind tonight’s storm system, substantially cooler weather will settle in over the weekend.  Temperatures will remain in the 40s all day Saturday, dropping below freezing Saturday night, then warming back up to the mid 50s Sunday afternoon:
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Then we warm right back up next week — Tuesday will be the warmest and driest day, before another good chance of showers and storms Wednesday cools us off for the remainder of the week:
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LINKS

Better late than never, your daily dose of nerdery…

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4WARN Weather Alert

A 4WARN Weather Alert is in effect for Friday night for the possibility of strong to severe thunderstorms.  As you know a warm moist spring-like air mass is hanging over Middle Tennessee.  A cold front in moving out the plains and mid west and set to arrive here tomorrow evening.  That is setting the perfect recipe for strong to severe thunderstorms to develop.  More on this in a moment.

Today the high reached 75 in Nashville, not a record, but very warm for late February.  Tomorrow a new record will likely be set with a forecast of 80 degrees.  The old record is 77.

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Another  high number tomorrow will be the pollen count in the medium high category.

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The front will approach tomorrow evening.  The Storm Prediction Center has areas north of I-40 in a “Slight Risk” zone, 2 on a 1-5 scale and the rest of Middle Tennessee in a “Marginal Risk” zone, 1 on a 1-5 scale.

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The greatest threat will be from damaging wind, but heavy downpours and some hail is possible.  Isolated tornadoes can not be ruled out.

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The timing is tomorrow night 6pm to 12mid, moving across the area west to east. Here’s the latest Futurecast depiction.

Cold air spills in for the weekend. Saturday will be a very chilly 49 degrees for the high and it will be dry.  Sunday dry during the day with a high of 55 degrees, some showers move Sunday night. Temperatures continue rise Monday into the low 60s.  There will be a greater chance of rain.WSMV 4DAY FORECAST.png

I’ll have an update coming up tonight on Channel 4 News at 10pm.

Lisa Spencer

 

 

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Friday Storm Timeline and Weekend Chill

Oh my stars. What an incredible sunset after a spring-like day in Middle Tennessee and it’s a view right from our back yard here from our studio at Channel 4. See our tower? Lucky for me, we have live cameras from in-studio which allows me to enjoy from a window view. video-tvi

Temperatures are STILL in the lower 70s as I type here (5:37 PM) about TWENTY degrees warmer than average.wsmv-dma-temps-zoom1_effectsquiggle-autoplot

Well, Mother Nature did not think it has been warm enough and is ready to crank things up even further on Friday! We are talking record-breaking territory… If my forecast pans out as expected, we will set a new record, breaking the previous 77 degrees set back in 1890.

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This is very brief , though! Significantly COOLER weather returns by the weekend and it all has to do with an approaching cold front currently draped through Oklahoma and Texas.

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Things remain dry tonight through most of the day on Friday. Only noticeable difference? Increasingly breezy southerly winds, with gusts as high as 35 to 40 mph at times. Most of the day is DRY. Once we get into 6:30/7 PM, a cluster of showers and thunderstorms will work their way in from west to east. Here’s what I’m expecting timeline-wise through Middle TN…

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What you need to know:

Some storms could be strong to severe. While the greatest threat will be damaging wind, an isolated tornado and hail cannot be ruled out.

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Here’s the latest from the Storm Prediction Center…

Good chunk of Kentucky and NE Middle TN are under a ‘Slight Risk’ (2 out of a 1 to 5 scale) and the remaining area of Middle TN is under a ‘Marginal Risk’ (1 out of a 1 to 5 scale).

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Once this front pushes out and about late FRiday night, we are in for a major cool down. We’re talking 30 degrees of a difference in the matter of a day — from 80 degrees on Friday to the upper 40s by Saturday. We’ll wake up to sub-freezing temperatures on Sunday morning. Welcome back, February, right?! Well, just for a day and a half… temps gradually warm back into the lower 60s by Monday before anothe rround of lower 70s return by Tuesday. Boom!wsmv-4day-forecast

Be sure to stay tuned for updates on these approaching storms! Chief Meteorologist Lisa Spencer will be with you all night and Paul will have updates bright and early on Channel 4 at 4 in the morning for all our early birds.

Have a blessed night!

-Meteorologist Daphne DELoren

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February 23: Weather Roller-Coaster, Daily Links

WEATHER

Patchy dense fog this morning is burning off as I’m typing this…we’ll see a mix of clouds and sunshine overhead the rest of the day.  Unusually warm temperatures once again — we’ll reach the low to mid 70s this afternoon:
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Warm and increasingly breezy tonight, with lows only dropping to around 60°:
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We’ll rocket up to near 80° by Friday afternoon!
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Tomorrow’s record high temperature is 77° set all the way back in 1890 — obviously it looks more likely than not that we’ll have a new record on the books.  The all-time warmest temperature for the month of February in Nashville is 84° — I don’t think we’ll be that warm, but I can’t rule it out.  It will be breezy throughout the day, with southerly gusts up to around 30 mph:
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The National Weather Service office in Nashville might decide to issue a Wind Advisory for tomorrow, but regardless of that you should make sure your lawn furniture and trash cans are secure.

Still a good chance of thunderstorms in the forecast Friday evening — the RPM model’s radar simulation shows them initially popping up around 6pm, then moving rapidly west-to-east throughout the evening and early overnight:
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Will the storms be severe?  That’s the million-dollar question at this point, but things are still looking “iffy” in terms of our severe potential in the Midstate.  The environment ahead of the storms will certainly be warm, and the wind energy overhead will likely be impressive…but the atmosphere won’t be all that humid, which is a major limiting factor.  Dew points are only forecast to be in the mid 50s Friday evening, which is really borderline:
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If you were designing a severe-weather environment, you’d want dew points to be at least 60°, and ideally in the mid 60s.  But the other ingredients are favorable enough for the one of the ensemble models (think of it as a “blend” of different forecast models) to indicate a chance anywhere from 20-50% of storms with severe weather ingredients Friday evening, highest to the northeast of Nashville:
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The “analog” forecast method (comparing Friday evening’s large-scale pattern to similar historical patterns) shows a 40% chance of 5+ severe weather reports Friday evening:
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Remember, “severe” means something very specific: 60+mph winds, 1″+ diameter hail, or a tornado.  Considering all of that data, the Storm Prediction Center has outlined a “Slight Risk” (level 2 out of 5) for severe storms in southern Kentucky and northeastern Middle Tennessee, with a “Marginal Risk” (level 1 of 5) for the rest of the Midstate:
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Damaging winds will be the main threat associated with any severe storms, but the way the winds will be arranged in the lowest 3 km of the atmosphere means I can’t rule out an isolated tornado — the greatest threat of severe weather will take shape to our north, in Indiana and Ohio.

Friday night’s storm system will bring in substantially cooler air for the weekend:
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But temperatures will turn right back around as we head through next week:
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Rain will move in from the west late Sunday night into early Monday.  Spotty showers (maybe a few storms?) on Tuesday with very warm temperatures, then another cold front will help to enhance our thunderstorm chances on Wednesday.  It’s WAY too soon to worry about any severe potential with that one.

 

LINKS

TONS of stuff about yesterday’s announcement from NASA.  Plus other assorted weather and science nerdery…

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49 Degree Temperature Drop

After days  of well above average temperatures a return to seasonal weather is set for this weekend. Today was another mild one, the high at 71 degrees in Nashville, average is 54. An approaching cold front will bring about the change this weekend, first with thunderstorms followed by a colder air-mass.

There is a deep layer of moist air over Middle Tennessee right now, this will spell a mostly cloudy night with some areas of fog and very mild temperatures. The strong southerly flow continues tomorrow, so expect a partly sunny to mostly cloudy day with temperatures about 20 degrees above average. I am throwing in a 20% chance of a shower, but most won’t see that. Pollen count will be in the medium-high category.  I feel for allergy suffers.

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Friday a cold front drops southward from the Midwest.  As the front approaches it will tighten the pressure gradient and that means a windy but warm day.  The afternoon high will be near 80 degrees, a record setter if we hit that.  The rain and thunderstorms will move in Friday night.  The Storm Prediction Center has put Middle Tennessee in a “marginal risk” zone 1 on a 1-5 scale.  We could be upgraded to a 2, “slight risk” zone.  The greatest threat will be high wind and  heavy downpours.

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Here is the latest timing with Futurecast. It’s all gone by Saturday morning. Then the cold air spills in.

Both Saturday and Sunday will be dry with seasonal highs in the mid 50s.  Sunday morning will drop down to below freezing, not good news for all the blooming plants.

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There is one activity were participants would love for Friday’s high to hang around Saturday. That’s the Hab-A-Splash benefit for Habitat for Humanity of Williamson-Maury.  It starts at 11am at the Westhaven Subdivision pool.  Snowbird and I will be there.  If you feel like a dip in the pool for a good cause, come join us.  Here’s the info and sign up click

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If you want to geek out with the weather nerds, you can come join the 4WARN Weather Team SWAD, Severe Weather Awareness Day. I will be speaking there Saturday morning at 9:30am. You can find out more and sign up just click here.

I’ll have a weather update tonight on Channel 4 News at 10pm.

Lisa Spencer

 

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