Client Brief: Severe Weather Event Overnight-Predawn Saturday…

Updated 12.10.21 @ 7:29a

Type: Severe weather event

The Storm Prediction Center has expanded both the ‘Slight’ and ‘Enhanced” risk zones northeast with the Friday morning update.

What: Severe weather outbreak

When: 12a to 8a Saturday, 12.11.21

Severe Risks: Damaging straight line winds and tornadoes

Summary: A strengthening surface low pressure system will lift northeast out of the central Plains this morning into the Great Lakes region by Saturday morning. A strong cold front will trail the area of low pressure and press east across Indiana Saturday morning. Ahead of the front, unseasonably warm and humid air will be drawn north to encompass most of the state. We’ll really notice a surge in moisture levels as we progress through the afternoon and evening hours. Dew points will rise from the 40s now into the lower and middle 60s all the way north to include central Indiana during the overnight and predawn hours Saturday. While CAPE (convective available potential energy) will be in question, which is typical with late fall/ early winter severe set-ups, the concern here is that we’ll be able to, unfortunately, make up for that with the influx of moisture and abundant shear.

Showers and perhaps a rumble of thunder (nothing severe) will increase by evening across central portions of the state, but it’s not until we get closer to midnight that stronger storms should get triggered. The focal point of this particular severe weather episode will fall within the 12a to 8a range. Initially, we believe there will be the opportunity of discrete super cells ahead of what should become a rather robust squall line that will move across the state (west to east) between 6a and 8a Saturday. The potential is present for all modes of severe weather, but given the dynamics in play, we’re most concerned for the potential of damaging straight line winds and tornadoes. It’ll be important to ensure you have a means of getting the latest warnings that will likely be issued tonight (be sure to set those weather radios alerts to “on”). Add in the fact that this event will take place when most people are sleeping, coupled with the likelihood of storms racing off to the east and northeast, it wouldn’t be a bad idea to give your neighbors and loved ones a friendly heads up of the developing weather situation later tonight so they, too, can prepare.

5p forecast radar: Rain will increase late afternoon and early evening with the potential of a rumble of thunder.
2a forecast radar: Individual super cells may try and develop shortly after midnight across the state. Damaging winds and the potential of quick spin-up tornadoes are possible.
7a forecast radar: A squall line will press across the state early Saturday morning with the threat of damaging winds and embedded rotating storms capable of tornadoes.

Confidence:High

Next Update: Friday afternoon- video

Client Brief: Severe Weather Event And Flash Flood Potential…

Updated 06.18.21 @ 5:37p

Type: Severe weather event

What: Severe weather event and flash flood threat

When: This afternoon through tonight

Severe Risks: Damaging wind, large hail, embedded tornado potential, flash flooding

Summary: A complex of thunderstorms to our north this morning will diminish. As a result, the cloud canopy engulfing much of the region this morning will give way to mostly sunny skies late morning and into the afternoon. Intense heat is expected this afternoon, courtesy of a southerly flow ahead of an approaching warm front and upper air disturbance. Highs will reach the lower to middle 90s this afternoon and heat indices will climb to between 100° and 105°. This heat, combined with a multitude of other ingredients: dew points into the 70s, convective available potential energy (CAPE) in excess of 4000 j/kg (suggestive of extreme instability), and steep low level lapse rates (rate of temperature change with height) all will play into what looks like a significant setup for a severe weather outbreak later this afternoon and tonight.

Initially, individual cells are likely to erupt (targeting mid to late afternoon) along an OFB (outflow boundary) across n-central Indiana. Damaging wind and large hail are the biggest concerns with these cells, but a tornado threat is also on the table in this highly unstable environment. Eventually the scattered, intense cells should congeal into more of a widespread storm complex by evening and impact most of central and southern parts of the state. Precipitable water values will be in excess of 2” and promote a flash flood risk, especially if thunderstorms back-build and train over the same communities. Should this be the case, localized rainfall amounts of 3”-4” will be a good bet. As we progress into the overnight hours, the storm complex and associated flood risk will shift downstate.

Confidence: HighN

Client Brief: Snow Builds In Overnight – Predawn Thursday…

Updated: 02.17.21 @ 4:54p

Type: Impactful Wintry Weather

What: Accumulating snow

When: 2a to 9p Thursday

Temperatures: 18° to 24°

Wind: N 10-20 MPH, shifting to the NW Thursday night

Blowing/ Drifting: Considerable  

Pavement Impacts: Plowing and salting will be required

Summary: Another round of snow will lift northeast into central Indiana during the overnight and predawn hours (likely arrives into Indianapolis between 1a and 2a). As like so many of these events in the past, this will be another cold storm, meaning we’re looking at another high ratio (15-20:1) event. The dry, powdery nature of the snow will be blown and drifted around by north to northwest winds of 10-20 MPH through the day. While heaviest snow bands should remain across southern and southeastern Indiana, I still expect the rather persistent nature of the snow tomorrow to add up to the tune of 1″ to 3″ for Indianapolis and surrounding areas. Travel will be impacted, including both the morning and evening rush hour. Eventually the snow will depart from southwest to northeast after dark, exiting Indianapolis by around 8p to 9p.

Skies will slowly clear up on Friday and lead to a dangerously cold night (similar to what we saw this morning) and Saturday morning.

Confidence: High

Next Update: Thursday morning

Client Brief: Periods Of Blizzard Conditions Tonight…

Updated 02.15.21 @ 1:18p

Type: Severe Winter Weather

What: Heavy snow & strong winds

When: Through Tuesday morning

Temperatures: Mid 10s, falling into the upper single digits by Tuesday morning

Wind: NE 15 – 25 MPH (gusts up to 35 MPH Monday evening)

Blowing/ Drifting: Severe  

Pavement Impacts: Plowing and salting will be required

Summary: A shield of snow will encompass all of central Indiana through the afternoon and into the late evening hours. Snow will become heavy at times by mid and late afternoon, continuing through the evening hours, including snowfall rates of 1″ to 2″ per hour. As the area of low pressure draws closer this evening, northeast winds will strengthen and gust up to 35 MPH. Periods of whiteout conditions can be expected around, or just after sunset. Falling snow will end from south to north by midnight to 2a. Strong and gusty northerly winds will continue into Tuesday morning leading to severe blowing and drifting, especially in the open country. In these areas, drifts of 3 to 4 feet are expected.

Confidence: High

Next Update: This afternoon (video)

Client Brief: Snow Builds In Overnight; Becomes Heavy Monday Afternoon Into Monday Night…

Updated 02.14.21 @ 12:29p

Type: Severe Wintry Weather

What: Heavy snow & strong winds

When: Monday morning – Tuesday morning

Temperatures: 16° to 21°

Wind: NE 15 – 25 MPH (gusts up to 35 MPH Monday evening)

Blowing/ Drifting: Severe  

Pavement Impacts: Plowing and salting will be required

Summary: Light snow will overspread central Indiana during the overnight, continuing through Monday morning. As the surface low moves northeast (up the Appalachian chain), snowfall rates will increase Monday afternoon into Monday night, becoming heavy at times. The cold nature of this storm system will lead to an efficient snow producer, including rates that will likely top 1″ per hour at times Monday afternoon into Monday evening. As the low moves closer, the pressure gradient will tighten and lead to strengthening northeast wind gusts (up to 35 MPH) for a period of time after sunset into the late evening hours. Travel is highly discouraged tomorrow, especially by afternoon and evening as the combination of heavy snow and strong winds will likely lead to some roadways becoming impassable. Drifts in the open country will likely reach 3 to 4 feet by Tuesday morning. Snow will end from southwest to northeast Tuesday morning.

*Our other products issued later tonight will handle the expected additional significant impacts with Storm #2.

Confidence: High

Next Update: Tonight (video)