Category: Rain

Mar 08

Saturday Morning Thoughts…

Filed under Forecast Discussion, Forecast Models, GFS, NAM Model, Rain, snow, Unseasonably Cool Weather, Unseasonably Warm
March 8, 2014

Good morning and happy Saturday! A weak weather system will move through the region and produce a couple of light showers this afternoon, but won’t be a big deal. Rain will end as a couple of snow flakes. Overall precipitation totals look less and less impressive with each model run, which wasn’t impressive to begin with. Needless to say, don’t be concerned by any sort of significant rain or snow today.

Latest simulated radar off the NAM and HRRR shows the band of light precipitation pushing through the state this afternoon.

While we’ll have a brief “set back” in the temperature department this weekend, early next week continues to look downright mild and very spring like. Note our region flirting with 60s. Impressively, a budding area of 70-degree warmth is expanding to our west.

Details remain quite sketchy in regards to nailing down the storm the middle of next week with any sort of confidence. While we’ll continue to sort through the data and gain a better understanding of things over the weekend, we’re confident on a colder regime returning by the middle of next week. Note the trough per the GFS ensembles returning to the east. Much more later!

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Mar 07

Beauty Of A Close To The Work Week…

Filed under 7-Day Outlook, Arctic Cold, Forecast, Forecast Discussion, Forecast Models, Rain, snow, Spring Tease, Unseasonably Cool Weather, Unseasonably Warm
March 7, 2014

Fri.	Sat.	Sun.	Mon.	Tue.	Wed.	Thr.

21/ 53	30/ 46	21/ 45	33/ 60	40/ 61	21/ 40	13/ 32
– – –	Light	– – –	– – –	– – –	Light	– – –

Forecast Updated 03.07.14 @ 7:30a

Get Outside & Enjoy…We’re going to wrap up the work week with beautiful conditions. If you can get out of work or school early today, IndyWx.com highly recommends it :-)! High pressure will support sunny skies (after a little morning fog in spots) and milder temperatures. Highs will zoom into the lower to middle 50s this afternoon!

Weak Weekend System…A weak cold front will slip south through the region Saturday. Early morning sunshine will quickly give way to increasing clouds and developing light rain. Rain will end as a period of light snow Saturday evening, but won’t accumulate. The key word in all of this is light, with rainfall totals under a tenth of an inch.

Sunday will be a dry, chilly day with highs in the middle 40s.

True Spring Feel…The spring crave will be in full effect early next week as highs both Monday and Tuesday shoot into the lower 60s with sunshine. We’ll notice a gusty westerly breeze Monday, assisting with the milder surge of air into the Ohio Valley.

Late Season Winter Storm Brewing? Many questions remain around the ultimate track of the storm system by the middle of next week. As of now, a blend of forecast model suggests a rain-to-snow scenario Wednesday, but it’s far too early to talk accumulations. We’ll be able to fine tune some things over the weekend and have a better idea soon in regards to precipitation type and amount. Regardless, a much colder air mass will pour into the region by the middle of next week.

Upcoming 7-Day Precipitation Forecast:

7-Day Snowfall Forecast: 1-3″
7-Day Rainfall Forecast: 0.10″ – 0.25″

For weather updates and more “behind the scenes” data on the go, be sure to Follow Us on Twitter @indywx or become a Friend of IndyWx.com on Facebook!

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Permanent link to this article: https://indywx.com/beauty-of-a-close-to-the-work-week/

Mar 05

“Trouble” Brewing Mid Month.

Filed under Arctic Cold, Canadian Model, European Model, Forecast Discussion, GFS, Rain, snow, Spring Tease, Unseasonably Cool Weather, Unseasonably Warm, Winter Storm
March 5, 2014

We continue to closely monitor the goings on towards the middle of the month- more specifically March 12th through the 14th. There are indications a significant late season winter storm is brewing and the overall pattern is one that is aligning itself in a way that certainly has to raise an eye brow. That said, it’s far too early for precise details. Is a major storm possible? Absolutely. Is it okay to pin down a given area for heavy snow totals at this stage? Absolutely not.

First, let’s take a look at the latest ensemble charts.

GFS

European

Canadian

At this stage in the game (more than a week away from the expected event), we suggest investing much more in the ensembles as opposed to a single operational model run. (Case in point just from today alone…the 0z run of the European suggested the interior northeast was ground zero for widespread 12″ type snowfall totals with little to nothing expected across central Indiana. Flip ahead 12 hours later and the 12z European takes the heavy snow axis through the heart of central Indiana on into the Northeast region).

Wikipedia has a nice write up on ensemble forecasting:

Ensemble forecasting is a numerical prediction method that is used to attempt to generate a representative sample of the possible future states of a dynamical system. Ensemble forecasting is a form of Monte Carlo analysis: multiple numerical predictions are conducted using slightly different initial conditions that are all plausible given the past and current set of observations, or measurements. Sometimes the ensemble of forecasts may use different forecast models for different members, or different formulations of a forecast model. The multiple simulations are conducted to account for the two usual sources of uncertainty in forecast models: (1) the errors introduced by the use of imperfect initial conditions, amplified by thechaotic nature of the evolution equations of the dynamical system, which is often referred to as sensitive dependence on the initial conditions; and (2) errors introduced because of imperfections in the model formulation, such as the approximate mathematical methods to solve the equations. Ideally, the verified future dynamical system state should fall within the predicted ensemble spread, and the amount of spread should be related to the uncertainty (error) of the forecast.

Though this is an event set to take shape close to a week from now, confidence on a significant storm across the east is higher than normal due to:

1.) Excellent agreement amongst the three primary mid range ensemble charts.

2.) The significance of the trough depicted on each set of ensembles.

While there are some differences, it’s highly unusual to see such relative agreement at this stage in the game. We continue to bracket March 12th through the 14th time period for potential impacts from this storm across central Indiana. Many questions will remain unanswered for now concerning precipitation type or amount, but we’re leaning more towards a winter weather maker at this early juncture for the Ohio Valley region. We stress this can, and likely will, change multiple times in the days ahead.

Regardless, we strongly agree with the week 2 temperature anomalies courtesy of the GFS. Should this come to fruition then March 12th through the 18th would feel more like early February then early to mid March. Again, we think the GFS is on to something with the return of the cold pattern.

As we move ahead know that we’ll be here keeping a close eye on the goings on behind the scenes around the potential “trouble” brewing for mid month. As we continue to dig into the details with this potential storm, you worry about finding ways to enjoy the spring like feel Friday and again Monday :-). We forecast both days to certainly have many craving spring as temperatures zoom well into the 50s both days. Get out there and enjoy it!

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Mar 02

New Work Week; Same Cold Feel…

Filed under 7-Day Outlook, Arctic Cold, Forecast, Forecast Discussion, Rain, snow, Unseasonably Cool Weather
March 2, 2014

Mon.	Tue.	Wed.	Thr.	Fri.	Sat.	Sun.

6/ 19	5/ 30	13/ 34	20/ 37	24/ 47	28/ 42	24/ 39
– – –	– – –	– – –	– – –	Light	Light	– – –

Forecast Updated 03.03.14 @ 7:55a

Brrrrrr…It may be a new work week, but the overall weather theme will remain an all-too-familiar one- COLD! A big, sprawling, area of high pressure will anchor itself over the region and result in temperatures well below where we would typically expect to be for early March. Instead of a high in the upper 40s, we’ll struggle to reach the 20 degree mark today. We’ll follow that up with yet another frigid night into Tuesday morning as lows sink to the single digits once more. Outlying ‘burbs may approach zero tonight and we call that “ridiculously cold” for early March :-).

Midweek Moderation, But Still Below Normal…Temperatures will moderate by the middle of the week, though remain below normal. We’re monitoring a weak weather system that will scoot north of the region Wednesday and this could move close enough to lead to an increase in cloudiness and a potential flurry or light snow shower Wednesday evening, but most should remain dry.

Keeping An Eye On The Weekend…We’ll continue to closely monitor next weekend. While model data certainly has yet to reach a consensus, we look to have somewhat of an unsettled weekend- at least on the front end. Stay tuned as we continue to fine tune things Friday evening into Saturday.

Upcoming 7-Day Precipitation Forecast

7-Day Snowfall Forecast: 1-2″
7-Day Rainfall Forecast: 0.25″

For weather updates and more “behind the scenes” data on the go, be sure to Follow Us on Twitter @indywx or become a Friend of IndyWx.com on Facebook!

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Permanent link to this article: https://indywx.com/new-work-week-same-cold-feel/

Mar 02

Accumulating Ice And Snow Then Frigid

Filed under 7-Day Outlook, Arctic Cold, Canadian Model, Forecast, Forecast Discussion, Freezing Rain, Rain, Sleet, snow, Unseasonably Cool Weather, Winter Storm
March 2, 2014

Sun.	Mon.	Tue.	Wed.	Thr.	Fri.	Sat.

16/ 23	9/ 19	4/ 28	10/ 30	18/ 38	27/ 50	22/ 37
Moderate	– – –	– – –	– – –	– – –	Light	Light

Forecast Updated: 03.02.14 @ 12:25a

Sunday Winter Storm…The well advertised winter storm is here and will make a mess of travel and plans for the second half of your weekend. Moisture is streaming northeast over a bitterly cold air mass locked in place at the surface and this will create a mixture of sleet and freezing rain to quickly change to a mixture of sleet and snow during the early morning hours across central Indiana.

We forecast precipitation intensity to really begin to increase across the greater central Indiana region around 3-4 am. Waves of accumulating snow will continue through the day, though it won’t snow all day. In particular, we bracket 4am to 10am and then again early Sunday afternoon.

Finally, a wave of low pressure will eject into the Tennessee Valley Sunday night into Monday, continuing the significant snow and icing down state. We anticipate the majority, if not all, of “round two” to bypass most of central Indiana to the south Sunday evening into early Monday. So, what’s the culprit behind the suppression? As mentioned in previous posts, a powerful arctic high will build south Sunday into Sunday night and this is the primary driver for the shift south in the surface low track.

All of that said, we’re still looking at significant accumulations of sleet and snow across central Indiana today, though reduced from the 6-8″ forecast we’ve had out since Thursday morning. We now forecast 2-5″ of snow and sleet across central Indiana. Needless to say, we’ll continue to monitor. Sunday night will turn downright frigid across the region as temperatures crash into the upper single digits.

As a quick side note, we once again have to tip our cap to the Canadian forecast model. It began to catch onto the southward shift with “phase 2” of the storm well in advance of the other model data (during the mid week period), including the highly touted European forecast model.

Frigid Start To The Work Week With Slow Mid Week Moderation…Fresh arctic air will be locked in place across the area to begin the new work week. While it’ll be dry, temperatures will run as much as 30 degrees below seasonal norms. The cold winter of 2013-2014 just doesn’t want to let up.

As we push into the mid week stretch we’ll note a powerful Gulf low that’s expected to push up the eastern seaboard. Early indications here keep us dry with slowly moderating temperatures. Though we’ll remain well below normal, it’ll be a step in the right direction, so to speak, from the frigid early week start.

Weak Late Week System…The early take on late next week shows a cold front moving through Friday afternoon and evening. This may create a few rain showers Friday evening followed by light snow Friday night into Saturday morning as a fresh push of cold air blows into the state. We have time to watch this and update as needed.