March 30th - 1st Potential Severe Weather Outbreak and Snow Potential

[Clinton]

It should be a noisy evening for many on here.  @OttumwaSnomow @Hawkeye and @bud2380.

  ...SUMMARY...
   Intense and widespread severe thunderstorms are expected this
   afternoon into the overnight hours across portions of the Middle
   Mississippi Valley and Mid-South vicinity, eastward to the Lower
   Ohio and Tennessee Valleys. Intense, damaging gusts and several
   tornadoes (some strong and long-track) are expected.

   ...Discussion...

   Strong, dynamic upper low will begin to deepen early in the period
   as it tracks across the central Plains into the Midwest Friday
   evening. This feature will encourage a pronounced surface low to
   eject into southeast NE by sunrise Friday, then into lower MI by the
   end of the period. Significant moisture return ahead of the
   associated cold front will lead to an air mass supportive of severe
   thunderstorms from the mid MS Valley/Midwest into the lower MS
   Valley.

   ...Mid-MS Valley/Midwest Vicinity...

   Early this morning, a strong upper trough is shifting across western
   WY/Four Corners region. An upper low should evolve over the central
   Plains by late morning with further deepening expected as the low
   tracks into the mid MO Valley by early evening. Latest model
   guidance suggests a 500mb speed max will increase to near 110kt as
   it translates across MO into the OH Valley during the latter half of
   the period. As a result, intense 12hr height falls, on the order of
   270-300m, will spread across the mid MS Valley/Midwest which should
   encourage the aforementioned surface low to deepen as it matures
   over northeast IA/southwest WI.

   Strong low-level warm advection is currently aiding a corridor of
   elevated convection from northeast NE across northern IA,
   along/north of a stationary front draped across this region. Latest
   thinking is much of the warm sector should remain convective-free
   through late morning until leading edge of stronger forcing spreads
   east in conjunction with rapid boundary-layer heating ahead of the
   cold front. Steep low-level lapse rate plume should develop across
   the central Plains early then spread/develop east-northeast across
   MO into portions of IA ahead of the front. Forecast soundings
   suggest convective temperatures will be breached by 18z immediately
   ahead of the low/front. Scattered supercells should develop quickly
   thereafter, tracking quickly northeast in response to the
   fast-moving upper trough/speed max. Discrete supercells should be
   the initial storm mode with very large hail expected. With time,
   strong forcing may lead to line segment and clusters. Strong shear
   will support long-lived updrafts. In addition to very large hail,
   tornadoes can be expected (a few strong) with these storms,
   especially prior to any line segment evolution.

   While the more concentrated storms should be noted across
   IA/northern MO into northwest IL, there is concern for more isolated
   long-track supercells across central MO into IL. All hazards can be
   expected with these storms.

[Clinton]

Nice snowfall on this mornings models from MSP to @Madtown

[Clinton]

3km NAM 

[Tom]

33 minutes ago, Clinton said:

3km NAM 

#Thundersnow wrapping up in the defo band should produce some pretty narly snowfall rates...

 

[BMT]

SPC just expanded risks again

[james1976]

Very dynamic system. WSW for 5-8" here. TC might move into top 5 seasonal snowfall after this.

[james1976]

We're going to the Lakers/Timberwolves game at the Target Center tonight. Could be a mess driving home afterward.

[Timmy Supercell]

38 minutes ago, BMT said:

SPC just expanded risks again

Good thing I scrolled up here, was going to post that. 

That has to be the biggest enhanced I've seen in a while.

[Hawkeye]

Quad Cities NWS is most concerned about the lead wave models are showing lifting up just to my southeast in early afternoon.  Those storms have already fired south of Kansas City this morning.  That wave should track into northern Illinois.  DVN is expecting any strong tornadoes to be in that area.

[Tom]

5 minutes ago, Hawkeye said:

Quad Cities NWS is most concerned about the lead wave models are showing lifting up just to my southeast in early afternoon.  Those storms have already fired south of Kansas City this morning.  That wave should track into northern Illinois.  DVN is expecting any strong tornadoes to be in that area.

I'm worried about N IL bc things are trending more significant as we get closer to the event... @Jaycee is prob getting pretty stoked!

[gosaints]

On the cold side what a wildcard setup.  The run to run changes on the HRRR are something

[Madtown]

Euro and GFS  now both showing a foot here...NAM went way south. HRRR south as well. Rap And RDPS showing a good hit here too...Let's get it on the ground...3.5" overnight

[Andie]

1 hour ago, BMT said:

SPC just expanded risks again

Interesting how the so called Tornado alley has moved east.  
Any opinions as to why?

[Phil]

Mesoscale guidance depicting one hell of a pressure surge with the cold front here tomorrow around sunset. Looks quick but if full mixing is realized that could produce 60-70mph gusts for an hour or two.

Which wouldn’t be long enough for a HHW, but some kind of headline would be needed. In 2017 when something like this happened the NWS issued severe thunderstorm warnings to cover it.

Edit: High Wind Watch posted just as a posted this.  

[Hawkeye]

[Iceresistance]

DOUBLE HIGH RISK

[Timmy Supercell]

[gabel23]

Holy smokes things are about to hit the fan. I don't think I have ever seen wording like this: Tornado Driven High Risk?! 

 

The NWS Storm Prediction Center has issued a

   * Tornado Watch for portions of 
     Central and Eastern Iowa
     Western Illinois
     Northern and Central Missouri
     Southwest Wisconsin

   * Effective this Friday morning and evening from 1145 AM until
     800 PM CDT.

   ...THIS IS A PARTICULARLY DANGEROUS SITUATION...

   * Primary threats include...
     Numerous tornadoes expected with a few intense tornadoes likely
     Widespread large hail and isolated very large hail events to 3
       inches in diameter likely
     Widespread damaging wind gusts to 70 mph likely

   SUMMARY...Intense supercell thunderstorms are expected to develop
   this afternoon and spread eastward across the watch area. 
   Tornadoes, large hail, and damaging winds are all possible with this
   activity.  Parameters are favorable for the potential for
   strong/violent tornadoes and very large hail.

[gabel23]

Yeah look at the individual cells already making their way up into a loaded gun area. Scary situation setting up for you folks in Iowa and Illinois. Sad part is this things are going to get going with school going on. 

[Cfweather]

17 minutes ago, gabel23 said:

Yeah look at the individual cells already making their way up into a loaded gun area. Scary situation setting up for you folks in Iowa and Illinois. Sad part is this things are going to get going with school going on. 

A lot of schools are letting out early.  I just hope it’s early enough. 

[Timmy Supercell]

Don't often look at TWC, but this was posted on their FB. 

[bud2380]

21 minutes ago, gabel23 said:

Yeah look at the individual cells already making their way up into a loaded gun area. Scary situation setting up for you folks in Iowa and Illinois. Sad part is this things are going to get going with school going on. 

Almost every school in eastern Iowa is letting out early.  My kids are getting out in an hour.  We are even sending employees home at 2pm here at work.  

[shakjen]

2 minutes ago, bud2380 said:

Almost every school in eastern Iowa is letting out early.  My kids are getting out in an hour.  We are even sending employees home at 2pm here at work.  

Same in central illinois

 

[gabel23]

Well I'm praying for you all!! I have a ton a family members who live in Des Moines too. Craziest set up day I have seen in a long time. Not even the tornadoes down south last week had this type of environmental setup. 

[CentralNebWeather]

We are heading down to KC, Shawnee KS western suburbs, after school today to see my brother and family for the weekend.  We are 40 degrees currently with winds gusting to 25 out of the NW and a dew of 30.  KC right now is mid 70's with dews in the low 60's.  Always amazing to me and my brother the differences between us weather/climate wise, with it only be a little over 5 hours from here.

[Iowawx]

1 hour ago, Hawkeye said:

How do you think things are looking for CR?

[Hawkeye]

We've hit 70º.  The cloud shield from the storms is overspreading eastern Iowa, so we are likely done with the sunshine and probably won't get much warmer.

[Clinton]

Nice warned cell moving overhead right now.  Stay safe up in east Iowa and Illinois, these storms are explosive and moving fast.

[Stormy]

1 hour ago, Hawkeye said:

We've hit 70º.  The cloud shield from the storms is overspreading eastern Iowa, so we are likely done with the sunshine and probably won't get much warmer.

Never had much sunshine here. Some peaks at times. 71° with dews in the 60⁰s. Definitely feels like tornado weather, and it's almost showtime though I wouldn't be surprised storms will be quite scattered in my area. 

[Hawkeye]

Look out Ottumwa.

[Stormy]

A tornado warned cell is going to be kind of close to my area so I'll probably be out watching soon! Speak at you later. 

[Iceresistance]

Little Rock has gotten hit by at least an EF-3 Tornado.

[Hawkeye]

No idea why, but the tornado sirens just sounded in Cedar Rapids.  There is no threat anywhere near us.

[Hawkeye]

It currently appears everything will be going around Cedar Rapids.... southeast and northwest.

[BMT]

16 minutes ago, Hawkeye said:

It currently appears everything will be going around Cedar Rapids.... southeast and northwest.

Just hoping for rain as I had some sod laid yesterday

[bud2380]

Tornado warning now for my backyard. 

[bud2380]

Large confirmed tornado just to my southwest. 

[Northland09]

Just got placed into a Blizzard Warning. I can't remember the last time we were in a Blizzard Warning. Antsy to see how this all plays out. Just spotty showers at the moment, but the wind has really picked up in the last hour. It's going to get very messy once it switches over.

[East Dubzz]

Seems like this tornado by Iowa City is heading more North than East?

[East Dubzz]

Lot of tornado warnings in E Iowa, but are the ones by Iowa City the only confirmed sightings?