Category: ClientBrief

Client Brief: “System” Snow Transitions To Lake-Effect…

Type: Impactful Wintry Weather

What: Accumulating Snow/ Wind

When: Today through Tuesday Morning

Temperatures: Upper 20s to lower 30s

Wind: NW 15-20 MPH; Gusting to 35 MPH

Blowing/ Drifting: Moderate, especially with late afternoon-evening lake-effect snow band.

Pavement Impacts: Salting required; plowing required within lake-effect snow band.

Summary: We’ll undergo a transition from “system” snow (mostly light) this morning into early afternoon to a more localized, but robust lake-effect snow event late afternoon and this evening. At least for central portions of the state, this is the better opportunity for accumulating snow. As temperatures continue to fall and the wind direction becomes better aligned, a band of lake effect snow is expected to develop initially across northwestern Indiana late morning. It’s this band of snow that should continue to get better organized and heavier as we move into late afternoon and the evening hours and be driven well inland. Eventually, this lake snow band should reach areas as far south as Indianapolis (and surrounding ‘burbs) by late afternoon, potentially including the 5 o’clock rush for parts of the city. Snowfall intensity within this band is expected to be heavy enough to whiten roadways and create slick spots. For most this will only last an hour or two before the band pivots east and impacts east-central Indiana for a longer period of time into the overnight and early Tuesday morning. If you find yourself under this lake effect snow band, a quick 1″ to 2″ can be expected

Confidence: High

Next Update: Tonight (video package)

Permanent link to this article: https://indywx.com/client-brief-system-snow-transitions-to-lake-effect/

Client Brief: Sunday Night – Monday System…

Type: Impactful Wintry Weather

What: Accumulating Snow/ Wind

When: Sunday night and Monday

Temperatures: Low-Mid 30s

Wind: N 15-20 MPH; Gusting to 35 MPH

Blowing Drifting: Minimal to Moderate in lake enhanced zone, as well as east-central IN

Pavement Impacts: Salting required; plowing likely required in lake enhanced zone, as well as east-central IN

Summary: While not nearly as robust as what guidance earlier this week printed out, the season’s first widespread wintry event looms Sunday night into Monday. This is a byproduct of phasing between the southern and northern jet stream (initially set off by the evolving strongly positive PNA), but there are important differences in the speed of the initial vort. max being a bit more progressive that will keep this from bombing out like earlier guidance showed. Consequently, this will result in a much further east system (may still not have seen that eastward trend finish). While our forecast specifically focuses on Indiana, if you have travel plans east of here into Ohio early next week, please pay special attention to the local National Weather Service products as impacts will be greater from heavy snow and strong winds.

Locally, we anticipate precipitation overspreading central Indiana (from southwest to northeast) around, or just after, midnight Sunday night. Initially, this should be in the form of a cold rain before precipitation transitions to wet snow prior to sunrise. Moderate snow should be falling across east-central Indiana from the mid morning hours Monday into early afternoon. Additionally, by this point, a more organized band of lake-effect snow should be firing up off Lake Michigan. This is a bit of a wild card as a combination of ingredients favor a pretty robust lake snow band making it further south than typical. As the wind direction veers towards more of a northwesterly flow late Monday afternoon and evening, it’s possible this lake effect snow band pivots into the Indy metro and surrounding ‘burbs. We’ll keep a close eye on this as time draws closer. Within this snow band, heavier accumulations are possible. Snow showers will continue into Tuesday morning before diminishing.

Confidence: Medium

Next Update: Tonight (video package, including longer range update).

Permanent link to this article: https://indywx.com/client-brief-sunday-night-monday-system/

Evening Client Video: From “Drought To Flood” Tonight For Some, Unfortunately; Early Next Week Also Presents A Problem…

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Permanent link to this article: https://indywx.com/evening-client-video-from-drought-to-flood-tonight-for-some-unfortunately-early-next-week-also-presents-a-problem/

Client Brief: Threat Of Impactful Wintry Event Increasing As Southeast Shift Continues…

Type: Impactful Wintry Weather

What: Accumulating snow and wind

When: Wednesday into Thursday morning

Temperatures: Middle 30s falling into the middle 20s by Wednesday night

Wind: North 15-25 MPH, increasing to 25-40 MPH Wednesday night and gusty

Blowing/ Drifting: Moderate to significant by Wednesday evening, continuing into Thursday morning

Pavement Impacts: Salting and plowing likely will be required

There has been a significant shift in the majority of model data today regarding the track of our midweek storm system. This has to do with a variety of elements, but most notably, the fact that the upper level energy at one time thought to come together to result in one primary storm during the first half of the work week, now looks to come in two parts: Monday into Tuesday, followed by a separate storm Wednesday into Thursday (this was what at one time was illustrated by the models a week+ ago). The debate now will continue for the next 24 hours around the deepening Storm #2 goes through, and this will have significant impacts on what central Indiana experiences in the Wednesday through Thursday time period. We think an initial wave of low pressure will organize along and just south of the Ohio River Tuesday night before tracking northeast and strengthening along the way into the eastern Great Lakes by Wednesday night. Should this, indeed, be the case, moisture would become widespread (after a relative “lull” Tuesday evening) across central Indiana Wednesday morning. With cold air funneling into the area by this time, the predominant precipitation type would fall as snow across central Indiana, including Indianapolis. Initially, this would be a wet type of snow before transitioning to a more powdery nature Wednesday evening.

As the storm begins to deepen to our northeast, blowing and drifting snow would become a concern on west-east roadways Wednesday evening into Wednesday night as the pressure gradient increases. By this time frame, north and eventually northwest winds would gust over 30 MPH with temperatures falling through the 20s. “System” snow would come to an end Thursday morning, but lake effect will continue across the traditional primary Snowbelt of northern Indiana (please note the amounts above do not account for the additional lake effect snow that would fall for Laporte, St. Joseph, and Elkhart counties). Additional lighter snow is a good bet for all as we close the work week out Friday, courtesy of upper level energy diving southeast across the state.

One additional note: We’ve been receiving a lot of questions around whether or not the southeast shift will continue with the model updates tonight. While some slight additional southeast movement in the axis of heaviest snow is still possible, there will be a limit due to the interaction between the deepening surface wave and area of high pressure. We will continue to keep a close eye on the data overnight and update things accordingly if needed early tomorrow morning.

Confidence: Medium

Next Update: Tuesday morning

Permanent link to this article: https://indywx.com/client-brief-threat-of-impactful-wintry-event-increasing-as-southeast-shift-continues/

Client Brief: Time To Gas Up The Snow Plows…

Type: Impactful Wintry Weather

A winter storm will impact the Ohio Valley through the 2nd half of the work week.

What: Accumulating snow and sleet

When: Wednesday afternoon through Thursday evening

Temperatures: Lower 30s falling into the 10s by Thursday evening

Wind: Southeast 10-15 MPH Wednesday afternoon shifting to the north Wednesday night and northwest Thursday. Winds will gust 20-30 MPH Thursday evening.

Blowing/ Drifting: Light to moderate by Thursday evening

Pavement Impacts: Salting and plowing will be required

A busy 48 hours awaits for central Indiana as a winter storm begins to impact the region. Mid and high level cloudiness will continue spreading over the region this evening and give way to a lowering and thickening cloud deck overnight and Wednesday morning. This is all thanks to a developing area of low pressure over the Ark-la-tex region. This surface low will track northeast into the TN Valley Wednesday and into the central Appalachians Wednesday night into Thursday morning. Long time residents of the Hoosier state know this is a favorable track for impactful wintry weather across these parts and this will be no exception.

Moisture will begin to lift northeast during the day Wednesday and reach the I-70 corridor around or just after lunchtime. Across the southern half of Indiana, this moisture should primarily fall in the form of a cold rain (perhaps a bit of sleet initially as the precipitation moves in). However, further north, trouble will ensue. The air won’t only be colder at the surface, but the depth of cold air will be much deeper. This will result in precipitation that should predominantly fall in the form of a sleet-snow “concoction” along and north of the I-70 corridor where we think an axis of 2″ to 4″ of snow/ sleet will accumulate with this storm- including Indianapolis. Further north, less sleet is anticipated and will result in heavier snowfall totals. The northern Indianapolis ‘burbs and points north to include Lafayette, Kokomo, Logansport, Ft. Wayne, and Muncie can expect 4″ to 6″ of snow with this storm system. Most of that will fall Wednesday afternoon into Wednesday night with additional lighter snowfall accumulation occurring with “wrap around” snow showers and embedded squalls Thursday afternoon into evening. (The Indiana Snowbelt (you know who you are :-)) can expect additional heavier snow accumulation, courtesy of lake effect).

A brief, but potent shot of arctic air will pour into the region Thursday afternoon and set us up for widespread single digits by Friday morning, including the threat of some sub-zero temperatures where the heaviest snowpack is laid down.

Confidence: High

Next Update: Wednesday morning

Permanent link to this article: https://indywx.com/client-brief-time-to-gas-up-the-snow-plows/