Jump to content
  • Member Statistics

    17,507
    Total Members
    7,904
    Most Online
    SnowHabit
    Newest Member
    SnowHabit
    Joined

Winter Storm - February 11-13, 2019


AppsRunner
 Share

Recommended Posts

3 minutes ago, cyclone77 said:

Just stepped out a bit ago, and it's pretty nasty out there when the wind picks up.  Getting some gusts over 25mph.  Hard to tell how much ice is on the trees due to the darkness, but it looks like a nice glaze has built up.  Luckily the winds should drop off a bit towards midnight, but the high winds later tomorrow could cause some trouble.  

EDIT:  I can hear the trees crackling in the breeze even inside the house now lol.

Time to bust this out?  I've never known if winds refers to sustained or gusts...

icesto3.jpg.44798843cbfff68e8eb317d37a4779c4.jpg

  • Sad 1
Link to comment
Share on other sites

Just now, hawkeye_wx said:

The mix crap has surged into Cedar Rapids, something I did not expect at all.  Our 1"/hr snowfall rate earlier has turned to garbage as the snow has turned into sleetish chunky flakes.  We can probably knock the 8-9" forecast down to 6-7".

I feel like we all consistently underestimate the WTOD. Every year, every borderline storm. Here I expected all sleet/snow, and have a significant potential ice storm unfolding 

  • Sad 1
Link to comment
Share on other sites

It's kinda strange around here.  We're hovering around 33-34 degrees with drizzle.  It's not freezing on the roads or the vegetation but it's also not melting (completely) our little minuscule 3 inch snow pack, may have lost an inch.  My unscientific measuring of ground temps around the yard are running 31-32 degrees with an air temp of 34.  Probably looking at 36-38 up around 5k feet from aviation reports.  Regardless it's messy slushy crap.

Link to comment
Share on other sites

The piece of guidance that had this scenario depicted pretty close to how it's unfolded is the NAM. I think the challenge in this setup is that you can think of a physical reason why a blend of the guidance would work out and how heavy rates could slow or even stall the advance of a warm nose.

Today we had our hourly update guidance suite (RAP/HRRR) with the fake out colder trend, and since the background field for SPC mesoanalysis uses that, it also had 850 temps colder than reality. Unfortunately there's no public access to aircraft soundings that would give non NWS/FAA a better idea of trends.

It's tough to throw all the eggs into the basket of one model, but a good lesson to err on the side of a more aggressive push of the warm nose aloft. In hindsight, it all seems simpler and makes sense.

Sent from my SM-G965U using Tapatalk

  • Like 4
  • Thanks 2
Link to comment
Share on other sites

URGENT - WINTER WEATHER MESSAGE
National Weather Service Chicago IL
959 PM CST Mon Feb 11 2019

...Messy Winter Weather Tonight into Tuesday...

ILZ010>012-019-121200-
/O.UPG.KLOT.WW.Y.0012.000000T0000Z-190212T1500Z/
/O.NEW.KLOT.IS.W.0002.190212T0359Z-190212T1500Z/
Lee-DeKalb-Kane-La Salle-
Including the cities of Dixon, DeKalb, Aurora, Elgin, and Ottawa
959 PM CST Mon Feb 11 2019

...ICE STORM WARNING IN EFFECT UNTIL 9 AM CST TUESDAY...

* WHAT...Significant icing. Total snow accumulations of 2 to 5
  inches and ice accumulations of up to three tenths of an inch.

* WHERE...Lee, DeKalb, Kane and La Salle Counties.

* WHEN...Until 9 AM CST Tuesday.
Link to comment
Share on other sites

7 minutes ago, RCNYILWX said:

The piece of guidance that had this scenario depicted pretty close to how it's unfolded is the NAM. I think the challenge in this setup is that you can think of a physical reason why a blend of the guidance would work out and how heavy rates could slow or even stall the advance of a warm nose.

Today we had our hourly update guidance suite (RAP/HRRR) with the fake out colder trend, and since the background field for SPC mesoanalysis uses that, it also had 850 temps colder than reality. Unfortunately there's no public access to aircraft soundings that would give non NWS/FAA a better idea of trends.

It's tough to throw all the eggs into the basket of one model, but a good lesson to err on the side of a more aggressive push of the warm nose aloft. In hindsight, it all seems simpler and makes sense.

Sent from my SM-G965U using Tapatalk
 

It is crazy how often the waa aloft is undermodeled.  Storm after storm, year after year.  I'd say you're almost better off starting from the position that the warmer model will be right and try to come up with a reason why it won't be.

Thanks for your contributions.  Really appreciated.

  • Like 4
Link to comment
Share on other sites

From an aviation perspective this is a fairly dangerous setup that has caught many pilots off guard.  There is a line from Central IL through N/Central IN that has a fairly low level melting layer above a much lower level freezing layer, roughly 2k-5k feet, that can catch an unprepared pilot off guard.  You normally encounter these setups much higher but this setup is lower and has/can present issues.

  • Like 1
  • Thanks 2
  • Sad 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...