Tuesday, February 4, 2014

Monday Night Update: Mid-Week Winter Storm

New evening data is in the process of coming in and I've had a chance to look over it.  A slight southward jog in the track of the storm is evident from the computer models.  Last night I mentioned that the storm was taking a Monroe, LA to Nashville, TN track.  Tonight's runs are taking it on more of a Jackson, MS to Lexington, KY track.  This would favor more snow development for areas of Illinois and Indiana.
0z GFS - 6pm CT Tuesday
(Click image to see larger version.)
While there is a southward jog to the track of the low (not by much), this does not mean freezing rain/sleet will not be an issue, especially in southeast Missouri, extreme southern Illinois and western Kentucky.  In fact, freezing rain could cause issues for extreme southeast Missouri and western Kentucky.  As far as icing is concerned, I do think we are talking less than 1/3" of ice for places like New Madrid, MO, Caruthersville, MO, Kennett, MO, and Paducah, KY.

A little further north, in places like Poplar Bluff, MO, Cape Girardeau, MO, and Vienna, IL there could be a glazing of freezing rain mixed with sleet and followed up by snow.

Areas near Columbus, IN and south will be borderline.  Several computer models suggest it will be cold enough to keep things all snow.  A few other models suggest a period of freezing rain/sleet before changing over to snow.

As for amounts of snow... I have gone through an put together another snow matrix so you can get an idea of what several of the computer models are suggesting.
(Click image to see larger version.)
(Click image to see larger version.)
As for how much snow I think will accumulate.

ILLINOIS:
  • Mt. Vernon: 4"-6"
INDIANA:
  • Columbus: 4"-8"
  • Indianapolis: 6"-9"
  • Lafayette: 6"-10"
MISSOURI:
  • Cape Girardeau: Up to 2"
  • Poplar Bluff: 1"-3"
  • St. Louis: 4"-7"
FREAK-OUT-METER

For those that don't know what my Freak Out Meter is, it is a number I give out that attempts to quantify how big of a deal the upcoming weather event will be. It is based on a 0-10 scale. Zero being the lowest, "not a deal at all", and 10 being "get all the bread, milk and eggs and lock yourself in the basement". The score is 100% subjective and it's an attempt to have a little fun.

ILLINOIS:
  • Mt. Vernon: 4
INDIANA:
  • Columbus: 5
  • Indianapolis: 5
  • Lafayette: 5
MISSOURI:
  • Cape Girardeau: 4
  • New Madrid: 6
  • Poplar Bluff: 4
  • St. Louis: 4
As always, be sure to follow me on Twitter (@johndissauer) as I often have more frequent updates there as opposed to writing a new blog post.

I'm going to be dealing with my own round of snow in Colorado (where I now work/live) Tuesday so time permitting, I'll try to update my blog Tuesday night.

Sunday, February 2, 2014

Starting February with Snow & Ice

There has been a lot of talk in the one to two weeks about a colossal storm heading for the Midwest this week.  A lot of the talk and hype has been extremely irresponsible, but that is a discussion for a different day.  It does appear a storm will impact the Midwest Tuesday and Wednesday.

One of the reasons I have been relatively quiet about the storm and its potential is due to the many different solutions computer models were coming up with.  Some had it as a HUGE ice storm, others as a HUGE snow storm and most had it somewhere in between.

Patience is a virtue sometimes when it comes to weather forecasting.  Let the models battle it out for a while and then start to come up with a somewhat unified solution to what the storm could do.

This is a storm that is going to develop over far southern New Mexico, western Texas and northern Mexico.  As it matures, moisture will become plentiful as it taps in to the Gulf of Mexico Tuesday.

Here is a solution the latest run of NOAA's Global Forecast model has come up with.  The image depicts 6pm CT Tuesday.
0z GFS - 6pm CT Tuesday
(Click image to see larger version.)
This is a classic winter storm for the Midwest.  The surface center of low pressure is tracking from around Monroe, Louisiana to just south of Nashville, Tennessee by Tuesday evening.  We're talking snow along and north of I-44 in Missouri and roughly along I-70 in Illinois.  This also means the rain/snow line is at play for southeast Missouri, southern Illinois and western Kentucky.

At this time, I do think all forms of winter precipitation will be possible for southeast Missouri, extreme southern Illinois and western Kentucky.  The primary nuisance will be rain, freezing rain and sleet.  There will probably be a change over to a little snow towards the end of the event.  The exact location of the rain/snow line is a little difficult to pinpoint this far out.  As you often hear meteorologists say, "The track of the storm will be extremely important." and this will be the case this time.  A change in just 40-miles will have a huge impact on what type of precipitation falls.

Right now, for places like Cape Girardeau, Paducah, and Poplar Bluff, I think rain, freezing rain and sleet will be the primary types of precipitation.  Icing could potentially be a concern, but let me say right now... This is NOT anything like the ice storm of 2009.  NO WHERE CLOSE.

TALKING SNOW

Let's talk a little snow for the Midwest.  I have gone through and looked at several computer model runs and have come up with a snow matrix.  Looking at the matrix can give you an idea of the range computer models are suggesting could happen through Wednesday night.  The data includes tonight's runs of the NAM and GFS and also Sunday morning's run of the European forecast agency's computer model as well as the 23-member SREF ensemble.
Missouri/Illinois Snow Matrix
(Click image to see larger version.)

Indiana Snow Matrix
(Click image to see larger version.)

Colorado Snow Matrix
(Click image to see larger version.)
As you can see, there is some variation between the computer models, but I must say, they are coming in to line with each other.

For many, the storm is still out 36 to 48 hours but I'll go ahead and throw out some ball park numbers.  I hope to update my blog tomorrow evening (time permitting) with fine tuned numbers.  Although, if you have followed my blog for a while, you know that my initially numbers usually only get slightly tweaked.  Think of it as a very time course correction.  But do know, these numbers can adjust as we get closer to the event.

COLORADO: (Monday night through Wednesday afternoon)
  • Colorado Springs:  3"-5"
  • Lamar:  5"-9"
  • Pueblo:  2"-4"
  • Springfield:  4"-6"
ILLINOIS: (Tuesday through Wednesday night)
  • Mt. Vernon:  2"-5"
INDIANA: (Tuesday through Wednesday night)
  • Columbus:  4"-8"
  • Indianapolis:  6"-8"
  • Lafayette:  5"-9"
MISSOURI: (Tuesday through Wednesday night)
  • Cape Girardeau:  Up to 1"
  • Poplar Bluff:  Up to 2"
  • St. Louis:  3"-5"
FREAK-OUT-METER

COLORADO:
  • Colorado Springs: 2
  • Lamar: 5
  • Pueblo: 2
  • Springfield: 4
ILLINOIS:
  • Mt. Vernon: 5
INDIANA:
  • Columbus: 5
  • Indianapolis: 5
  • Lafayette: 5
MISSOURI:
  • Cape Girardeau: 4
  • Poplar Bluff: 4
  • St. Louis: 3
For those that don't know what my Freak Out Meter is, it is a number I give out that attempts to quantify how big of a deal the upcoming weather event will be. It is based on a 0-10 scale. Zero being the lowest, "not a deal at all", and 10 being "get all the bread, milk and eggs and lock yourself in the basement". The score is 100% subjective and it's an attempt to have a little fun.

For more frequent updates, be sure to follow me on Twitter at @johndissauer.