Chris's Corner - Welcome to the Warmest Start Ever to Feb!

[Chris Higgins]

Getting close to the NAM being in range for Monday... but it's still not in it's good spot yet.
There is a noteable trend on the NAM though of slooooooower. Much slower.

[Chris Higgins]

God bless the icon for trying hard to make Monday interesting.

[mchafin]

Feb 9, 2024 21:22:37 GMT -6 Chris Higgins said:

God bless the icon for trying hard to make Monday interesting.

I just said a few minutes ago after looking at the ICON, “awww..isn’t she cute?”

[amstilost]

Had a very heavy shower about 15 minutes ago. Can hear rolling thunder off to my West. 7 miles west of DeSoto. Temp at a stupid 51*.

[Chris Higgins]

First Thunderstorm Warning of the year down south.

[Jeffmw]

Feb 10, 2024 0:01:05 GMT -6 Chris Higgins said:

First Thunderstorm Warning of the year down south.

Chris I Noticed there are new weather alert graphics. 

[Chris Higgins]

Feb 10, 2024 0:03:11 GMT -6 Jeffmw said:

Feb 10, 2024 0:01:05 GMT -6 Chris Higgins said:

First Thunderstorm Warning of the year down south.

Chris I Noticed there are new weather alert graphics. 

Yes. They went online today actually.

[RyanD]

Sure looks like there's rotation on that storm unless my eyes are deceiving me

[Chris Higgins]

Feb 10, 2024 0:25:27 GMT -6 RyanD said:

Sure looks like there's rotation on that storm unless my eyes are deceiving me

Most definitely is. Midlevel rotation... not sufficient for a tornado...but enough to emhance hail production.

[RyanD]

Feb 10, 2024 0:32:10 GMT -6 Chris Higgins said:

Feb 10, 2024 0:25:27 GMT -6 RyanD said:

Sure looks like there's rotation on that storm unless my eyes are deceiving me

Most definitely is. Midlevel rotation... not sufficient for a tornado...but enough to emhance hail production.

Yeah it doesn't have that classic tornadic hook. The rotation is easier to see now on the Paducah radar.

[cozpregon]

Storms are elevated

[ajd446]

NAM is coming north unfortunately its snowing during the day Monday

[Snowman99]

At this rate it'll be Monday EVENING commute where the issues are instead of morning. The more delayed it is the better chance of coming north. If it comes down hard enough, If it's 3 or 4 pm if it get down to 32 or 33 it should stick without too many issues.

[BRTNWXMAN]

Model trend is for the mid-level system to remain closed off a bit longer...I wouldn't be surprised to see the N trend continue. Definitely some potential for a slushfest for the Metro and points S. But it's as borderline as it gets, so we know how that usually goes.

[ajd446]

ICON is nice

[Worldserieschampions (Chicago)]

Look at the cold dome on the 12z Icon next weekend.

Wow

[MakeitRain]

Looks like an interesting trend. Will need to watch the models tonight!

[BRTNWXMAN]

Hi-res NAMs have several hours of moderate/heavy snow Monday afternoon across the Metro. Looks like the changeover happens quickly with wetbulbing and dynamical cooling...we'll see. As 99 said, the evening commute could be interesting if trends hold.

[Chris Higgins]

Multi-tasking today, but from what I've seen... the NAM is north, gfs is north, canadian is waaaaay south. The in house IBM model was waaaaay south and Icon is playing the role of tease and most consistent. However, the ensemble means are also consistently further south of operationals... including what we can see of the Icon.

So, at this juncture, I don't see the need to adjust what is out there in the public. STL metro is on the northern edge of some wet snow...probably no accumulation. The greatest potential for 1-3 inch snow is in a stripe from the Ozarks over to near Farmington.

The one trend that has been building is slower... so I have to give a nod to that. This now looks like a daytime event more than a morning event... which will further restrict potential for accumulation... especially within the UHI (urban heat island). A further delay of a few hours could make the early evening drive more interesting.

[BRTNWXMAN]

ICON looks a lot like the NAMs if not more amped.

[BRTNWXMAN]

00z UKIE is pretty far S for Monday but has an interesting looking Fgen event setting up towards next weekend along the cA boundary. Seems like models are starting to pick up on the effects of the strat warming event that's unfolding. Winter isn't over yet...

[Worldserieschampions (Chicago)]

Feb 10, 2024 10:44:50 GMT -6 BRTNWXMAN said:

00z UKIE is pretty far S for Monday but has an interesting looking Fgen event setting up towards next weekend along the cA boundary. Seems like models are starting to pick up on the effects of the strat warming event that's unfolding. Winter isn't over yet...

Starting to see signs of a PV split as well which would make the first half of March interesting.

[Chris Higgins]

The Euro is in. Quick look confirms we are on the right track at this stage. Steady as she goes!

[Snowstorm920]

Interesting look to the NAM Monday morning

Elevated instability intersecting the DGZ

[BRTNWXMAN]

The 3k NAM did have a bubbly convective look to it's sim radar product. It shows some 1"/hr+ rates over the Metro...assuming it actually accumulates and doesn't compact which isn't realistic but shows the SN+ potential.

[Snowstorm920]

Feb 10, 2024 14:28:29 GMT -6 BRTNWXMAN said:

The 3k NAM did have a bubbly convective look to it's sim radar product. It shows some 1"/hr+ rates over the Metro...assuming it actually accumulates and doesn't compact which isn't realistic but shows the SN+ potential.

A very convective look to it

Soundings like this will get your attention

[Snowstorm920]

From the afternoon discussion: 

Working our way from the top down, we have an upper level closed low approaching the Mid-Mississippi Valley by 12z Monday. Upper level divergence associated with the left exit region of an overhead jet streak will filter into the area early Monday morning. In the mid- levels (700-500 mb), forcing and ascent will be strong as well. DPVA will move overhead while mid-level moisture and warm air advection create a saturated DGZ with steep lapse rates (up to 7.0 C/km) overhead. Deterministic models actually pull up to 300 J/kg of MUCAPE above this layer, signaling the potential for a convective component within the band of heaviest snow. Mid-level frontogenesis is still strong as well, and the potential for narrow mesoscale banding is high. Although air and ground temperatures at the beginning of the event will be above freezing, within this band, dry low-levels will cause evaporative cooling to quickly saturate the column and pull down temperatures to near/sub-freezing values, creating the environment needed for snow accumulation. The ample forcing aloft and convective component of the storm will also create high to intense snowfall rates of 1+ inches/hour within the heart of the band. These rates can easily overcome warm ground temperatures and accumulate on roads. The potential for the band forming in the Ozarks only exacerbates this effect, as higher elevations will be cooler and more prone to accumulation than surrounding areas.
The question at this point isn`t if a mesoscale band will develop - it`s where - and we still aren`t 100% confident in that. Deterministic and ensemble guidance have shifted northwest with the system, which we`ve seen happen with recent snowfall events in our area. For this reason, the potential placement for the band has shifted northwestward to include areas along and south of I-70, including the Ozarks. To be clear, the band itself will not encapsulate this entire area. It`ll be a very narrow strip, but could set up anywhere within this range. Snowfall amounts within the band are forecast to reach 4+ inches with amounts dropping drastically just outside of it. Precipitation will continue to move northeast through the afternoon before exiting entirely Monday evening.

[guyatacomputer - NE St. Peters]

As Chris said several days ago this sounds very much like a March or April snow event

[Snowman99]

18z gfs, lol

[showtime - Marissa]

At least it’s trending better lol