Category: Forecast Models

Jan 16

Another Brutally Cold Pattern Setting Up…

The coming several days will result in a continuation of adding to an already expanding snow pack across central Indiana. (We think a 3-5″ band of snow falls for some central Indiana communities Saturday evening and we’ll post on this Friday).  That “ups the ante” for a potentially second round of cold air that flirts with records as we begin to wrap up the month of January and head into February.

Here’s a look at the latest ensemble package out towards Days 8-10 (Jan 24th-26th time period) and we note a near text book pattern for a severe arctic outbreak across the eastern half of the country.  We want to point out the high latitude blocking combined with a frigid cross-polar fetch.  The GFS and European forecast models (amongst a slew of others) are in excellent agreement on the brutally cold pattern setting up shop, which only adds to our confidence level.

arctic

Okay, okay…the fancy maps above may look confusing to some (and rightfully so), so what does all of this mean to you?  We think we’re looking at multiple nights that feature below zero low temperatures across central Indiana, and potentially in the double digit below zero range yet again.  (Wind chills will be even colder).  We’re looking at the type of cold pattern that could produce multiple days with high temperatures in the single digits to lower teens.

Yes, the winter of 2013-2014 just keeps on keepin’ on and truly shows no signs of letting up.  Hunker down, friends!

Permanent link to this article: https://indywx.com/another-brutally-cold-pattern-setting-up/

Jan 15

Reviewing The Snowy Details…

After a brief thaw, winter’s set to return with authority in the days and weeks ahead.  In fact, the overall long range weather pattern looks colder and snowier than average into early February, at least.

A current look at the National Radar shows the next clipper system taking shape to our northwest this evening.

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A dive into the latest model data continues to highlight two distinct opportunities for accumulating snowfall in the days ahead.  The first comes Thursday into Friday while the second (potentially more robust) snow maker arrives Saturday afternoon and evening.  By the way, my hat’s off to the GFS for jumping on Saturday’s system well in advance of the other modeling.  Sometimes it’s easy to hammer the GFS, but it should be pointed out during the model’s shining moments, as well.

Back to the near-term… We think widespread snow overspreads central Indiana Thursday morning and continues through the majority of the day and on into Friday in varied intensity.  By the time all is said and done, 2-4″ of new snowfall will be likely across central Indiana, with some locally higher amounts possible.

Here’s a look at the latest HRRR simulated radar valid 10am Thursday. Some moderate to briefly heavy snow is possible late morning into the afternoon.

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Of interest, we note forecast models carrying a vigorous upper level disturbance across the state Thursday night/early Friday and this will help carry accumulating snow into Friday for some.

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We’ll note an intrusion of briefly drier air Friday afternoon into Saturday morning, but by this time all eyes will be focused on the next clipper system that promises to keep snow shovels and plows busy for parts of Indiana into the weekend.  We think snow overspreads the region from northwest to southeast Saturday afternoon and evening.  Steadiest snow falls Saturday night and could accumulate to the tune of a few inches by daybreak Sunday within the axis of best moisture.  Just to the north of the clipper’s track will be where you find the highest snow totals with Saturday’s system and the precise track of this clipper will be tough to iron out with any sort of certainty until Friday evening.  Stay tuned.  By the way, the snowy and cold events keep on keepin’ on in the longer range…

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Permanent link to this article: https://indywx.com/reviewing-the-snowy-details/

Jan 15

Series Of Fast Moving Snow Makers…

A series of fast moving snow makers will make for busy times in the good ole forecast office in the days (and weeks) ahead.

Of course we’re dealing with scattered snow showers this morning, but this really isn’t a big deal as accumulations will be nothing more than a dusting for most communities.

Our next clipper system will deposit light snow and snow showers across the region Thursday and Friday.  Short-term, high resolution data, highlights the chance of some light accumulation Thursday into Friday- generally an inch or less for most.  Here’s a look at the latest simulated radar valid Thursday morning at 8am and Friday at 4am:

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We then look ahead towards Saturday when potentially the best shot of accumulating snow arrives.  The GFS has been leading the way on this system and now other forecast models are following it’s lead.  It’s important to note that these northwest flow systems can be over-achievers (as mentioned in previous posts) and the “fluff effect” can really kick into gear thanks to high snow ratios with the cold air.  We’ll continue to monitor this.  As of now, we think a few inches of snow is possible Saturday as this clipper moves through.  Stay tuned…

gfs_ptype_slp_east_15gfs_ptype_slp_east_16

Permanent link to this article: https://indywx.com/series-of-fast-moving-snow-makers/

Jan 14

Challenging Northwest Flow…

We’ve made mention of this in the past and we bring this up again as the upcoming weather pattern is one that’s predictable in one sense, but very challenging in another.  We know it’s going to get colder, that we’re confident on.  That said, models will continue to struggle with the details of snow chances, associated with clipper systems diving southeast into the region.  Issues with timing and snowfall amounts are common in these patterns up until 24-48 hours prior to the event.

Case in point, let’s take this weekend. Three forecast models are handling snow chances differently in the Friday-Saturday period.  The European model and Canadian are jumping more on Friday snow (light accumulations), while the GFS is focused on Saturday snow (again, light accumulations)…

Which is the correct solution?  It’s a tough call at this point, but we’ll go with a blend of the three for now, focused on best accumulating snow chances (1-2″ variety) coming late Friday into Saturday morning.  That said, as mentioned above, it’s a tough call and this will require fine tuning as we move forward.  Make it a great day!

The European and Canadian forecast models are honing in on Friday for best chance of light accumulating snow:

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Meanwhile, the GFS is focused on Saturday for best snow chances:

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Permanent link to this article: https://indywx.com/challenging-northwest-flow/

Jan 09

Bet On The Colder Look…

Sometimes in life there are things much more important than the weather and so has been the case the past few days. Moving forward, posts will be a bit erratic,…

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Permanent link to this article: https://indywx.com/bet-on-the-colder-look/