Category: Forecast

Feb 05

Accumulating Snow Isn’t Finished

Good morning!  After a night complete with impressive snow totals, lightning and thunder reported downtown shortly after 6am, and significant drifting in the open country, things have “calmed” as of this post.  That said, the accumulating snow isn’t finished and will rotate back into central Indiana by late morning.

We think an additional 1-2″ of snow will fall with the highlighted area of snow below as it tracks east-northeast.  This snow is courtesy of the upper level low moving through the region.  Our storm total here at IndyWx.com HQ- 5 miles northwest of Zionsville is at 8.6″ so far.

ULSnow2514

Permanent link to this article: https://indywx.com/2014/02/05/accumulating-snow-isnt-finished/

Feb 03

Here We Go Again…

Yet another winter storm is bearing down on the region and will promise a snowy time of things here Tuesday evening into Wednesday.

Surface low pressure will begin to organize over the lower Mississippi River Valley Tuesday morning and move northeast…eventually into PA before a secondary low takes over off the Northeast coast Wednesday.  We like our track of the storm below.

TueWedStormTrack

 

 

 

 

 

 

This will really be the first storm that’s tapped into Gulf of Mexico moisture since the major winter storm that pounded our area early last month.  Moisture will be plentiful with this system and, when combined with the cold air, will lead to significant snow accumulation for most of central Indiana, with significant ice accumulation expected downstate across southern sections of Indiana.

We think snow begins to develop across central Indiana as early as early to mid afternoon Tuesday, but the heaviest of the snow will fall Tuesday night into the wee morning hours Wednesday.  In fact, snowfall rates may approach 1″ per hour for a time Tuesday night, especially where the heavy snow bands set up.  Just exactly where do these heavy bands of snow develop?  It’s a very tough call, but thinking at this juncture would suggest mainly north of Indianapolis.  Additionally, latest data suggests a thundersnow report or two may occur tomorrow night within the heavy snow bands.  Snow will begin to taper from west to east Wednesday morning, but the open country will have to deal with some blowing and drifting through the day Wednesday as the low departs northeast.  We’ll then enjoy a dry and cold couple of days as arctic high pressure builds in before our next winter storm develops for the weekend…

We forecast widespread 4-8″ (localized 8″+ totals possible within convective heavy snow bands) of snow to accumulate by the time all is said and done across central Indiana and our call right now is for the greatest chance of those 8″ reports to fall within the highlighted zone below.

HVY Snow Totals 020414:020514

Quick Bullet Point Thoughts:

  • Snow develops towards 3-4pm Tuesday.
  • Heaviest snow falls Tuesday night into the wee morning hours Wednesday.
  • 4-8″ of snowfall expected across central Indiana, with heaviest totals from Indy’s northern suburbs and points north.  Locally heavier totals can be expected within the heavier convective snow bands.
  • Significant ice accumulation of 0.25″, or greater, possible down state
  • Placement of embedded heavy snow bands will have to be monitored closely Tuesday night and may be accompanied by thunder and lightning.
  • Snow begins to diminish Wednesday morning, but blowing and drifting continues through the day.

The dry slot, originally mentioned here Sunday, will likely impact southern and south-central Indiana late Tuesday night into Wednesday morning and will essentially shut off the accumulating snow threat south of I-70 during the wee morning hours Wednesday with some light freezing rain and/ or freezing drizzle glazing over the snow that falls.  Meanwhile, accumulating snow will begin to taper Wednesday morning north of I-70.  The latest high resolution NAM simulated radar, courtesy of Weatherbell Analytics, shows this well.

Dryslot1

Permanent link to this article: https://indywx.com/2014/02/03/here-we-go-again/

Feb 02

Initial Snowfall Ideas; No Let Up In Sight With This Pattern…

As we approach the time for many Super Bowl parties to kick off, we wanted to go ahead and post some initial snowfall numbers for our upcoming winter storm Tuesday afternoon into Wednesday.  It’s important to note that model data will be able to fully sample the storm later tonight so we’ll fine tune things Monday morning, but here’s our early idea…

We think snow (wintry mix across south-central Indiana) moves in as early as Tuesday afternoon, with the period of heaviest precipitation falling Tuesday night into the wee morning hours Wednesday.  This will be a quick moving storm and, as such, will impact precipitation totals from reaching even higher amounts.  Additionally, we’re also noting the chance central and southern Indiana gets into the dry slot late Tuesday night into Wednesday morning.  As of right now, our forecast snowfall totals are based on 1. a relatively fast moving storm system and 2. the current likelihood of being dry-slotted across portions of central Indiana.  It will be important to note where the all-too-popular (for snow lovers) deformation zone sets up shop as heavier snow totals, in excess of half a foot, will likely fall within this band.  Additionally, an icy mixture of sleet and freezing rain may fall across south-central Indiana (current thinking places this icy mix south of I-70) and this could lead to tree limb and power line damage in spots.  Stay tuned…

Here’s what area radars may look like Tuesday night into Wednesday morning.  This data is courtesy of the fine folks over at Weatherbell Analytics.

2021

 

 

 

 

 

 

 

 

 

 

 

Our thinking hasn’t changed on the overall track of the low (track map originally posted here Saturday night).

TueWedStormTrack

 

 

 

 

 

 

 

 

Quick Bullet Point Thoughts:

  • Snow will overspread central Indiana Tuesday afternoon
  • Heaviest snow will fall Tuesday night- where it remains all snow 4-6″ is our initial call
  • An icy mix of sleet and freezing rain could lead to significant ice accumulations down state (greater than 0.25″ ice accumulation)
  • Closely monitoring the forward motion of the storm and potential dry slot working into the region late Tuesday night-Wednesday morning

By the way, we’re tracking another winter storm for the upcoming weekend and we’ll discuss this in more detail in the days to come… Enjoy the game!

Permanent link to this article: https://indywx.com/2014/02/02/initial-snowfall-ideas-no-let-up-in-sight-with-this-pattern/

Feb 02

More Thoughts On Our Next Winter Storm…

As we continue to draw ever closer to our next significant winter storm, we wanted to provide some of our latest thoughts.  This isn’t a post that will hash out…

You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access.  Already a member of IndyWx.com All-Access?  Log-in here.

Permanent link to this article: https://indywx.com/2014/02/02/more-thoughts-on-our-next-winter-storm/

Jan 31

Accumulating Snow Saturday Night?

In the short term, a wintry mix of sleet, freezing rain, and snow will transition to all rain across the entire region Saturday.  That said, if traveling early Saturday morning, please leave extra time to reach your destination and plan to take it slow on the roads as a mixed bag of wintry precipitation will fall on central Indiana tonight.  Most snow accumulations will range from 1″ or less.

After a cold and damp Saturday, we’ll have to pay close attention to the chance of snow mixing with the rain Saturday evening before possibly turning rather quickly to a heavy, wet snow Saturday night/ wee morning hours Sunday.  A cold front will slip south Saturday evening.  Additionally, a disturbance will move slowly northeast along the pressing front and result in widespread precipitation falling on the back side of the boundary (in the colder air) late Saturday night into Sunday morning.  As of Friday evening, guidance suggests a frontal passage in the city between 6-7 o’clock and cold air will begin to filter back into the region at that time period.

2

While we’ll have to keep a close eye on things during the afternoon Saturday, confidence is growing on the opportunity for a stripe of accumulating snow being laid down through central Indiana late Saturday night into the wee morning hours Sunday.  Just how much?  We wouldn’t be surprised if some amounts of 2-3″ are reported by daybreak Sunday, including in, and around, the greater Indianapolis region.  Most of this snow would accumulate within two-three hours so this will be what we call a “thumping” snow.  Stay tuned.

Permanent link to this article: https://indywx.com/2014/01/31/accumulating-snow-saturday-night/

Jan 30

Complicated And Complex…

If you have travel plans across central Indiana Friday and Friday night, please make sure you leave plenty of time to get to your destination and prepare for a variety of precipitation types.  In fact, it’s entirely possible (depending on what time of day you’re traveling) that you have to deal with rain across south-central Indiana and snow by the time you arrive into the northern Indianapolis suburbs, complete with an icy mixture “in between.”

Digging through the weather playbook for Friday into Saturday:

A cold front is expected to move through the region Friday morning, allowing a wind shift out of the north to arrive into the city in the early to mid morning Friday. We’ll have to be in “nowcast” mode Friday to determine just exactly how far south the front makes it as this will go a long way into determining precipitation types across central Indiana.

Ultimately, a wave of low pressure will move along the front Saturday, which will help milder air push north and result in a changeover from a wintry mix to all rain during the majority of the day Saturday. In fact, there’s the chance portions of central Indiana may not have to deal with much, if any, precipitation through the majority of the day Saturday- especially south.  Before that, however, we’ll have to deal with a wide variety of wintry precipitation issues Friday and Friday night…  Warmer low level air will be drawn northward and overrun the colder air at the surface Friday and Friday night.  What will initially be a period of snow Friday will transition to an icy mixture of sleet and freezing rain Friday night and all rain Saturday.  That said, we note the milder push will be brief, and colder air will pour back into the region on gusty northwest winds Saturday night. This may result in a brief period of light snow Saturday night (not a big deal).

We think the latest high-resolution, short-term, NAM model (courtesy from the fine folks over at Weatherbell Analytics model suite) has a very good handle on accumulation ideas Friday and Saturday and is in best agreement with our analysis laid out above.  This is a look at forecast snow accumulation between now and Saturday night, but we also note there will be some light sleet and freezing rain accumulation on top of any snow that falls Friday. As far as that snow goes, we think a 1-2″ band is laid down from the city and points north, increasing further as you travel into north-central and northern Indiana.

hires_snow_acc_indy_18

 

 

Permanent link to this article: https://indywx.com/2014/01/30/as-promised-complicated-and-complex/

Jan 29

A Word About Early Next Week…

We posted earlier this morning on the near term (below) and Friday and Saturday remain quite challenging and complicated.  Precipitation type and amounts will have to be resolved as we…

You must be logged in to view this content. Click Here to become a member of IndyWX.com for full access.  Already a member of IndyWx.com All-Access?  Log-in here.

Permanent link to this article: https://indywx.com/2014/01/29/a-word-about-early-next-week/

Jan 26

Arctic Front Hits Tonight With Wind And Snow Squalls

Today will be briefly milder as a nice southwesterly air flow develops and helps send temperatures close to 40 degrees for the city, itself.  Though winds will be gusty, 40 degrees will seem awfully nice!  Enjoy!  It won’t last long though as our next major arctic front already has it’s eyes set on our region.  In fact, we think snow showers and embedded heavier squalls arrive just prior to midnight. These will be short, but intense, bursts of snow and will be capable of producing white out conditions, as well as leading to a quick 1-2″ of fresh snow tonight for many across central Indiana.

Here’s a look at forecast radar tonight, showing the heavy bursts of snow during the overnight.

12

Winds will once again become a problem, gusting in excess of 30 MPH and helping drive in some dangerously cold air.  We think we fall below zero early Monday morning (before the rush hour begins in earnest) and anticipate yet another horrible Monday morning commute.

3

This arctic air really tightens it’s grip heading into Tuesday and we think lows approach 15-20 degrees below zero Tuesday morning.  Below zero readings make it as far south as the southern Appalachians.

We’ll deal with yet another, potentially more widespread, winter event late in the week.  More on that in the coming days…  Enjoy your Sunday!

Permanent link to this article: https://indywx.com/2014/01/26/arctic-front-hits-tonight-with-wind-and-snow-squalls/

Jan 24

1st of 3 Rounds Of Wind-Whipped Snow This Weekend!

The first of three rounds of accumulating, wind-whipped, snow is blowing into central Indiana as I type this.  We still think widespread 2-3″ totals fall across many central Indiana neighborhoods during the overnight, with snow ending from north to south between 6-8am.  Additionally, blowing and drifting snow will be a huge concern and local white-outs/ near blizzard conditions will develop into the morning Saturday.  Needless to say, if you don’t have to travel tonight or Saturday, it would be a great time to hunker down at home, start a fire, and enjoy friends and family!

Here’s a look at forecast radar during the “height” of the storm, most likely between 2-4a for most areas:

3

Snow will end Saturday morning, but we’ll have to contend with continued severe blowing and drifting, especially in central Indiana’s open country.  Remain cautious if you must venture out.  Winds will back around from the southwest during the wee morning hours Saturday to a colder (yet again) northwest direction late Saturday morning, resulting in another bitter feel to the air Saturday afternoon.

We’ll enjoy a brief calm period Saturday evening (despite continued gusty winds), but our meteorological eyes will already be poised to the northwest, focused on our next round of accumulating snow Sunday morning. We call this “warm advection” snow as it’ll fall on milder southwest winds ahead of yet another arctic front due in here Sunday night.  This will likely be a  “thumper” snow as additional accumulation Sunday of 1-3″ is a solid bet at this point- most of which falls within a 2-3 hour time period.

2

Sunday afternoon will likely turn drier (and briefly milder) before that “famous” arctic front slams into the region Sunday night. We think additional snow showers and embedded heavier squalls will accompany the frontal passage (FROPA) and could easily lay down yet another half inch to one inch of accumulation Sunday night/ early Monday.

4

All of this additional weekend snow will be capped off with some of the most brutally bitter air so far this season (and that’s obviously saying something, considering how cold it’s been). Gusty northwest winds will lead to continued blowing and drifting issues in the open country early next week, but produce dangerous wind chill values, colder than 30 degrees below zero from time to time.  Additionally, overnight lows Monday night into Tuesday morning will likely fall to between 15 and 20 degrees below zero and highs on Tuesday will likely struggle just to make it to the 0 degree mark for a high…

Permanent link to this article: https://indywx.com/2014/01/24/1st-of-3-rounds-of-wind-whipped-snow-this-weekend/

Jan 23

Combo Of Snow & Wind Likely To Cause Problems…

We wanted to take some time to focus solely on our next shot of accumulating snow due in here late Friday night into early Saturday morning.  This will be a quick-hitter, but with snow ratios much higher than normal (thanks to the arctic air mass in place), it won’t take much moisture to fluff up a few inches of powder.

Before we get into the next snow, we can’t ignore what will be a growing concern as morning progresses into afternoon Friday.  The pressure gradient will really begin to tighten between arctic high pressure to our south and the next cold front and associated low pressure to our north.  West winds will increase and gust in excess of 30 MPH by early to mid afternoon.  This will lead to concerns for blowing and drifting in the open country from the existing snow pack in place.  Otherwise, mostly sunny skies will begin to cloud up later in the afternoon and evening.

1

A continued very windy evening will be coupled with light to moderate snow spreading south over the region late Friday night into Saturday morning.  We note the heaviest snow likely to fall in the pre dawn hours Saturday and may become briefly heavy at times.  We forecast 2-3″ of new snow with this system across all of central Indiana, but when you combine a strong west wind, shifting to the northwest Saturday morning, trouble will result.  Significant blowing and drifting snow can be expected through the night and into Saturday.  Travel will likely be very tough late Friday night into Saturday morning.  Not only will we have to contend with severe blowing and drifting, but we’ll also have to deal with local white-out conditions.

The latest high resolution model data shows widespread snow across the region Saturday morning before snow tapers by mid morning from north to south.

hires_ref_streak_indy_34

As mentioned in posts from earlier this week, we’ll also deal with yet another round of accumulating snow for the second half of the weekend and we’ll have more on this tomorrow and Saturday…

Permanent link to this article: https://indywx.com/2014/01/23/combo-of-snow-wind-likely-to-cause-problems/

IndyWx.com