Category Archives: GFS

More On This Weekend’s Winter Storm…

As we’ve been discussing, a significant winter storm is developing this weekend.  The set up is one that will feature an arctic cold front sinking south and stalling out across southern and central Indiana Saturday night.  Low pressure will then organize over the Ark-la-tex region and head northeast, tracking into the northern Tennessee Valley Sunday and Sunday night.  The low will move off the southern Mid Atlantic coastline Monday evening.  This will be more of a prolonged event when compared to our last two winter storms as waves of moderate to heavy snow move into central Indiana beginning late Saturday night.

This is an ominous set up for more heavy snow across central Indiana- one that’s notorious for heavy snow events across central Indiana.  We hoisted our initial snowfall forecast Thursday morning and placed central Indiana under the threat for 6-8″.  As of this morning, we’re remaining firm on that idea.  It should be noted that the GFS remains very bullish on heavier totals (and consistent, as well), but it should also be pointed out it’s somewhat of an outlier as of this morning as the GEM and ECMWF are more suppressed with lighter totals.  All of that said, we lean more towards the GFS solution versus the more suppressed Canadian and, to some extent, European forecast model.  Should the other model data begin to trend towards the snowfall idea per the GFS then the initial 6-8″ forecast will have to be adjusted upward.  The storm is just now coming onshore and will be sampled better with model runs later today.

Any way you slice it, a significant and disruptive winter storm is brewing this weekend and could make an absolute mess of your Sunday and Monday.  A shot of bitterly cold air will flow in behind our departing storm early next week.

Our current accumulation idea and storm track can be found below:  We’ll have another update here late tonight and you can keep up-to-date with all of our thoughts on the go on Twitter (@indywx).

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WinterStorm030214Totals1

No Comments Arctic Cold, Canadian Model, European Model, GFS, Sleet, snow, Winter Storm

Next Week’s Spring Tease Is Just That, A “Tease…”

There’s no doubt we’re looking at a brief pattern change next week that will result in air temperatures that will have many of you craving spring.  That said, the key word in that sentence is “brief” and a colder, more wintry pattern looks to return to wrap up February and head into March.

Before we discuss the return of the cold and potentially wintry regime for late month, let’s focus on the milder conditions.  Data suggests we may be looking at highs zooming all the way into the lower to middle 60s towards the 20th-23rd time period.  The spring tease is likely to come at a cost as the milder southerly breezes likely result in lots of dense fog and areas of drizzle as a deep snowpack remains locked in place.  Flooding concerns may also become a concern next week, especially if we inject moderate to heavy rain into the region.  10-day rainfall numbers do have to make us a little nervous as a blend of model data suggests 1″-1.5″ down between now and the 22nd.  We’ll continue to monitor things.

Finally, it should be noted that while a brief “relaxation” of the seemingly unending winter is on the way, the long term pattern continues to suggest a cold and wintry time of things continues overall.  Next week appears to be an “island of warmth in a sea of cold” type pattern.  Latest ensemble data continues to back this idea up.  That’s not saying we’re going to deal with the type of severe cold we’ve seen over the past several weeks, but instead means we’re going to go back below normal as we get set to wrap up February and head into March.

The latest GFS ensembles show the evolution of things well.  The “double secret probation” European model also shows something similar.

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Note the ridge and associated spring “tease” is replaced with a cold and more wintry looking eastern trough rather quickly.  Circle the 24th on your calendar for the potential of a widespread storm system.  Far too early for details or questions, but the pattern looks to produce some busy times around this point.  Before that we have plenty of weather in front of us to deal with… weekend snow opportunities, foggy/ drizzly weather to accompany the initial surge of milder air next week, and a spring tease by late next week!

No Comments Arctic Cold, Flooding, Fog, Forecast Discussion, GFS, Heavy Rain, Long Range Discussion, Monthly Outlook, Rain, snow, Spring Tease, Unseasonably Cool Weather, Unseasonably Warm

Watching The Pattern Turn Active Yet Again…

After a dry period through early to mid week, our weather pattern will begin to turn active yet again as we head into late week and this weekend.  Three of our more trusted mid range computer models handle the individual impulses of energy differently and the snow potential ranges anywhere from nothing more than 1″ to as much as 10″ in the Friday-Tuesday period.  Most likely, we’re looking at something somewhere in the middle.

Our first chance of accumulating snow arrives Friday.  Both the European forecast model and Canadian forecast model agree on this, while the latest GFS takes the same energy through the Great Lakes, missing our region entirely.  We feel the GFS may be in error mode here.  While it’s possible the GFS may lead the way (anything is possible this far off), we feel the EC and Canadian have a better handle on things and we’ve based our forecast (post below) off a blend of these two models for Friday, including accumulating snow.

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Our next shot of accumulating snow blows in Saturday.  All three models agree on this, but handle the track of the low, another clipper system, differently.  The Canadian tracks the low south of IND, strengthens it on it’s journey east and results in a full blown snow storm here Saturday.  The GFS and EC remain weaker and track the low across central or northern parts of the state, with much lighter snow amounts here.

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You can find your completed 7-Day forecast in the post below this one.  Finally, there are some signs the pattern may begin to relax and allow a milder brand of air into the region around the 20th.  We caution though that this won’t be a “suddenly it’s spring” pattern, but rather a tease of sorts as longer term signals suggest a wintry regime returns late February into March…

No Comments Canadian Model, European Model, Forecast Discussion, Forecast Models, GFS, snow