Category Archives: Forecast

Serious Winter Storm Takes Aim On Indiana

We awake this morning to most of the data very consistent with what we’ve been passing along to you over the past few days…a very serious winter storm is taking aim on Indiana and will result in a combination of significant weather events that ultimately may end up being something we’ll remember for quite some time…

Quick Bullet Points:

  • Snow develops early Saturday morning
  • Heaviest snow falls between 10a-5p
  • Wind increases through the day Sunday and gusts in excess of 30 MPH leading to white outs and severe blowing and drifting
  • Temperatures crash to 10-14 below zero Monday morning with wind chill values of 40 to 50 below zero.
  • Widespread snowfall of 5-9″ is likely across central Indiana, with a heavier band of 9-12″ including Indianapolis and running along and just north of the I-70 corridor on the south side north to include Vermillion to Adams counties on the north side.

This is a hazardous and severe winter weather event that will likely lead to road closures from the heavy snow and wind, as well as extremely dangerous conditions to spend anytime outdoors Sunday into early next week due to the cold.  The bitter wind chills will be capable of frostbite in less than 30 minutes to any exposed skin.

Latest model data shows consistency in precipitation amounts, or QPF. We’re showing you the GFS, Canadian, and European models below.  Please note that the numbers and maps below don’t show snowfall amounts, but show precipitation totals.  Bring in a 12-15:1 snowfall ratio with these numbers and you get the snowfall discussed above.  We’re leaning heavily on a Canadian/ European model blend as the GFS has been more erratic.

gfs_total_precip_east_9cmc_total_precip_east_10ecmwf_tprecip_indy_10

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Much more later this evening!

Arctic Cold, Blizzard, Forecast, Forecast Discussion, Forecast Models, snow

Triple Threat Of Dangerous Winter Weather Ahead…

You can always catch your latest 7-Day Video Forecast in the video player to the right of this post.

We continue to be very impressed with what’s ahead, winter weather-wise, for central Indiana over the course of the upcoming 10 days.  Simply put, what’s at stake is a 10-day period of winter weather that could rival the all time greats in terms of snowfall and cold.  It’ll certainly be interesting to watch things unfold in the days ahead.

Here are some quick-hitting bullet points of what we’re eyeing…

  • Accumulating snow late tonight-Thursday
  • Accumulating snow late Saturday night-Sunday
  • Coldest air since 1994 early next week
  • Dangerous cold and wind chill values to 40 degrees below zero

First things first and that’s tonight’s and Thursday’s snow event. We think snow becomes widespread across central Indiana prior to, or around, midnight.  The low pressure system that will aid in snow production across our region Thursday AM is organizing across the central Plains this evening and this will move east northeast with time between now and Thursday morning.

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Latest high-resolution simulated model data shows the snow increasing in coverage across central Indiana around midnight.

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We think the period of heaviest snow comes during the early to mid morning Thursday and will result in a horrible rush period on area roadways.  Accumulating snow ends by noon and is replaced with falling temperatures, gusty northwest winds resulting in blowing and drifting, and scattered lake-driven flurries.

All eyes will then shift to storm number two set to arrive late Saturday night into Sunday.  An arctic boundary will moves towards the region Saturday night and Sunday and help surface low pressure develop.  All of our medium range models (GFS, Canadian, European) are on board with a developing surface low in the Ark-la-tex region late Saturday night/ early Sunday morning and can be seen below.

gfs_ptype_slp_east_16cmc_precip_mslp_east_17ecmwf_slp_precip_mc_17

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

There are still some questions that we have in regards to the extreme snowfall forecasts off some computer models, and we’ll stick with our initial call made here last night of an additional 3-6″ of snow late Saturday night-Sunday for now.  We come up with that range based off an all model blend, including raw numbers, operational data, and ensembles.  An extremely strong arctic high pressure system will be plunging south and will limit how far north the heavy snow makes it.  That said, snowfall ratios and an initial impressive thermal gradient will lead to a heavy snow storm for some parts of the Ohio Valley region Sunday.  Stay tuned.

As early next week approaches (and I’m all settled in to enjoy what I hope to be Auburn’s second National Championship in 4 years), the coldest air since 1994 will be blowing into the region.  Downright dangerous wind chill values of 40 degrees below zero will be possible Monday into Tuesday and result in extremely dangerous conditions to be outdoors for any period of time.

Here’s a look at the latest wind chill idea:

plotterForecast lows of 15 to 20 degrees below zero will be likely early next week across central Indiana with afternoon highs struggling to make it to zero.

Prepare now for a significant triple threat punch of snow and cold in the days ahead. Stay tuned!

7-Day Outlook, Arctic Cold, Forecast, Forecast Discussion, Forecast Models, snow, Windy

Colder Than Normal Pattern Set To Return

Before we go into the cold pattern that is looming, our current forecast of severe flooding developing across central Indiana this weekend remains.  Our projected precipitation numbers remain in the 3-4″ range for most of central Indiana, but there will be some higher totals reported.  Combine that with the recent snow melt and the stage is set for potentially a severe and dangerous flooding event.

As we look ahead to the next weather “challenge,” it has to do with temperatures.  As we’ve talked about in previous posts, our weather pattern flipped to one that has been predominantly colder than normal back in the middle of October.  Despite a handful of days, cold has dominated the pattern.  Before our current thaw temperatures were averaging 5 degrees below normal for the month of December.  While the recent thaw is certain to reduce the anomalous cold, the last week of December could send us right back to readings much colder than average, helping put the exclamation point on the month as far as cold goes.

The latest 8-10 day ensemble plots showcase a very cold pattern to end December.  Cross polar flow gets involved, helping lead to some bitterly cold air around these parts.  We note excellent agreement between the GFS and European forecast models, helping to further increase our confidence in the cold pattern ahead.

test8

But it doesn’t stop there…  We note long range data suggesting this cold pattern continues well into January.

The latest European forecast ensembles showcase the cold continuing to reload into the first week of the month.  This is an impressively cold look, considering we’re still a couple weeks out and that these are a multitude of individual computer model runs averaged together to come up with this solution.

eps_t2min_anom_east_61

As we watch the evolution of the cold pattern, it’s important to turn to the “goings-on” with the upper air pattern.  Note the reorganization of the polar vortex and, equally as important, the placement of the polar vortex.  For the purpose of giving you a couple of different viewpoints of the evolution of the pattern we’ve pasted a Northern Hemisphere and North America perspective.

Note how the polar vortex reorganizes itself and decides to set up shop over Hudson Bay and Baffin Island by early January.  This is significant in that it promotes multiple reinforcing shots of arctic air into the eastern half of the country and backs up what the data above would suggest in the cold pattern that appears to be looming as we move forward…

Sunday, December 22nd

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Friday, January 3rd

34

What does all of this mean?  That the current “thaw” is very brief.  The seeds were being planted for a return of the cold pattern earlier this week and it all begins Sunday night.  As the data above would suggest, the arctic cold appears to reinforce itself as we go through time and an overall prolonged colder than normal pattern appears to be setting itself up.

Additionally, we’ll have to handle winter storm systems as they come (and they will), but the pattern is one that very well may promote fast-moving clipper systems moving southeast out of Canada.  While most of these clipper systems don’t drop tremendous snowfall totals, the more potent clippers can deposit several inches of snow and serve to “feed back” and turn what’s initially a cold, dry pattern into one that’s suddenly snowy.  We’ll keep an eye on that.  Furthermore, the southern stream may also decide to add a little “excitement” into our forecast late December or early January.

Needless to say, there’s a lot of weather to talk about in the days ahead…

Arctic Cold, Christmas/ Thanksgiving, Forecast, Forecast Discussion, Forecast Models, Heavy Rain, snow, Unseasonably Cool Weather

Model Data Not Backing Down On Flooding Rains Ahead

A scan over multiple computer models this morning shows that forecast models remain consistent of the idea of a weekend deluge across central Indiana.  Unfortunately, when combined with the snow melt, if even the numbers are half right, we’ll have to deal with significant flooding this weekend, especially Saturday afternoon through Sunday.

Here’s a look at the data.  We average multiple computer models together to come up with our precipitation forecasts (both rain and snow) that you see in our daily 7-Day Video Forecasts (available to the right of this post).

CAN1EC1gfs_total_precip_east_11hires_ptype_acc_indy_20NAM1plotter

Needless to say, when looking over all of the data above, we still feel confident in the forecast we have out…widespread 3-4″ rainfall with locally heavier totals.  Preparations should have already begun if you live, or work, in a flood prone area, but if not, please do so today.  The question remains not if we’ll see flooding, but how severe the flooding will be.

Forecast, Forecast Models, Heavy Rain

Thursday Morning Weather Rambles

As always, your latest 7-Day Video Forecast can be found to the right in the video player.   1.) A milder southerly air flow allowed us to remain above freezing…

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7-Day Outlook, Arctic Cold, Christmas/ Thanksgiving, Forecast, Heavy Rain, snow, Snow/Ice Cover, Unseasonably Cool Weather, Unseasonably Warm