Category: Severe Weather

Thursday Morning Rambles…

1.)  Morning showers and thunderstorms continue to impact north-central Indiana this morning and given the look to downstream trends on radar and satellite, it would seem like it’s going to be tough to get into any sort of significant sunshine this afternoon. This is great news as it’ll limit severe potential.  That said, we still can’t rule out a severe thunderstorm this evening with large hail and damaging straight line winds of greatest concern.  The updated (9a eastern) outlook from the Storm Prediction Center continues the “enhanced risk” for the southern half of Indiana.

2.)  We bracket the hours of 2p-8p (couple hours earlier from yesterday’s thinking) as the period of potential most widespread strong to severe thunderstorms across central Indiana, and the HRRR forecast radar shows what the radar may look like this evening. Have a means of getting the latest warnings.

3.)  Scattered showers will continue into Friday morning before drier air arrives during the evening hours.

4.)  This drier trend Friday PM is one that will continue into the weekend.  High pressure will supply mostly dry weather through the entire weekend (small shower chances return Sunday evening), including sunshine.

5.)  Another active period of weather awaits next week, including multiple rain chances early and late week.  The latter storm looks to be the bigger event with heavy rain and thunderstorm potential Wednesday into Thursday.  7-day rain numbers check in between 1.5″-2″ with locally heavier amounts.

6.)  The story becomes a chilly one next weekend, and models suggest central Indiana may be dealing with frost and freeze conditions by next Saturday or Sunday morning.

Permanent link to this article: https://indywx.com/2017/03/30/thursday-morning-rambles-2/

Timing Thursday Storms…

Happy Wednesday!  Today’s sunshine sure was nice and I hope you had an opportunity to get outside and enjoy it.  Unfortunately, the pleasant weather won’t last as a storm system begins to impact central Indiana as early as the overnight period.  Clouds will continue to thicken tonight and showers and thunderstorms (non-severe) will arrive during the predawn hours.

We note short-term, high resolution, forecast radar data brings the initial wave of thunderstorms through the city during the 2a-3a time frame early Thursday morning.

Multiple rounds of showers and thunderstorms will likely impact central Indiana through the mid and late morning hours Thursday.

As we press into the early afternoon hours, model data suggests we see a “lull” in the stormy weather and potentially even a few breaks in the cloud cover.  This would serve to “up the ante” in regards to the prospects of severe weather potential Thursday afternoon, particularly mid and late afternoon through the evening hours.  Accordingly, the Storm Prediction Center continues to highlight central Indiana for the risk of severe weather Thursday.

In fact, given a look at the most recent data, I wouldn’t be surprised to see the “enhanced” risk area expand further north in future updates.  This would also include all modes of severe weather (large hail, damaging straight line winds, and potentially a tornado). As things stand this evening, we bracket the hours of 4p and 10p Thursday for the greatest potential of severe weather.

Forecast radar paints a stormy picture Thursday evening and, as mentioned above, a few of these storms could become severe.

As we push into the overnight hours Thursday into Friday, unsettled weather will continue, but we’ll get rid of the severe potential.  “Nuisance” type showers will continue into the first half of Friday before drier air arrives Friday afternoon and evening.  This drier theme will settle in for the weekend and provide a very pleasant open to April.

Ensure you remain weather-aware Thursday and have a means of getting the latest warnings.

Permanent link to this article: https://indywx.com/2017/03/29/timing-thursday-storms/

Looking Ahead Into Early April…

Month-to-date, Indianapolis is running near seasonal norms from a temperature standpoint (0.50° above normal).  Chill has dominated the northern tier and eastern third of the country.

Precipitation is running above normal, locally, to the tune of nearly 1″ month-to-date.  Heaviest rains have fallen across southeastern Indiana over the past (30) days.

A look at precipitation anomalies across the mid west, month-to-date:

As we progress through the upcoming (10) days, a transient weather pattern will persist.  This will keep forecasters busy, but it should also be stressed it’s not all a “doom and gloom” type pattern, either.  There will be plenty of dry time over the upcoming period, including drier conditions building in tomorrow (Tuesday) into a good chunk of Wednesday.

By Wednesday night/ Thursday morning, shower chances will begin to increase and that will set the stage for a wet close to the work week as numerous showers and embedded thunder move across the region Thursday into Friday.  This is courtesy of a storm system “bowling” through to our south.  This won’t be a severe weather maker for our neck of the woods, but will serve to create a rather damp and gloomy regime during the aforementioned period.

However, timing is our friend this go around as upper ridging develops over the upcoming weekend.  Not only will we dry out, but we’ll also enjoy increasing sunshine as the weekend progresses.

That said, looking further down the pipe line, another (potentially more significant) storm system looms during the 8-10 day period.  This would fall in the April 3rd-4th time frame.  From this distance, models are bullish on hefty rainfall totals with this storm system and we’ll keep a close eye on things as time draws closer.

Speaking of April, our overall thoughts for the fourth month of the year (where does time go?) would imply a warmer than average month and active (wetter than average).  Relative to average, we feel we still may have some chill to traverse early month, but there’s also some indication we could bust into an early summer-like feel mid and late month.  With the mean trough position west and ridging east, we’ll have to also be mindful for the potential of an active severe weather month- especially mid and late month.  Overall, the CanSIPS idea below is one we would agree with from a mean 500mb perspective.

Permanent link to this article: https://indywx.com/2017/03/27/looking-ahead-into-early-april/

Thursday Morning Weather Rambles…

1.)  All of a sudden what was a warm March has revered big time.  Officially, Indianapolis is running close to 1° below normal on the month and will continue to fall further once today’s data is factored in.  Always fun to see Mother Nature “balance” things out.

2.)  It’s another cold start to the day with many central Indiana neighborhoods in the teens and hard freezes extending south into Florida this morning.

3.)  Sunshine can be expected today and after the frigid beginning, a moderating trend will begin this afternoon that will send temperatures into the lower to middle 40s.  That’s still close to 10° below average for daytime highs, but will feel much better than what we’ve been dealing with over the past several days.  Add in that high March sun angle and it’ll actually be a very pleasant afternoon.

4.)  Unfortunately, we won’t hang on to the sunshine for St. Patrick’s Day.  A warm front will lift northeast through the region during the overnight and lead to an increase in clouds by evening.  A wintry mix of sleet and freezing rain will impact central IN predawn Friday morning before transitioning to showers mid-to-late morning.  “Light” is the key word here with models suggesting less than 0.20″ total.  By Friday afternoon we’re back to dry times.

5.)  We’ll turn a touch cooler Saturday and it’ll be a blustery day, as well.  A couple of early snow showers are possible across east and northeast portions of the state before afternoon sunshine returns.  High pressure settles in overhead Saturday evening and will set up a nice second half of the weekend- lots of sunshine and milder temperatures by Sunday (lower 50s).

6.)  Looking ahead, the quiet times will be hard to come by as we progress through the latter portions of the month.  Both the new JMA Weeklies (shown below) and other ensemble guidance is bullish on a wetter than average close to the month, and also one that features wild temperature swings.  Thoughts shift back to severe prospects, especially for our friends to our south and the potential of backlash wet snow showers in the colder air.  From a temperature perspective, it’s a pattern that will be very “transient” with no true long-lasting periods of significant warmth, or cold- relative to average.

Permanent link to this article: https://indywx.com/2017/03/16/thursday-morning-weather-rambles-4/

VIDEO: Busy Night Of Severe Weather On Tap…

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Permanent link to this article: https://indywx.com/2017/02/28/video-busy-night-of-severe-weather-on-tap/

Active Severe Weather Night Ahead…

The updated outlook from the Storm Prediction Center shows an expanded “Enhanced Risk” to encompass all of central Indiana.

This morning’s showers and thunderstorms were the first of (3) rounds of storms expected today.  Ironically, most of the daytime hours should be rain and storm-free.  We’ll note scattered showers and thunderstorms across northern portions of the state this afternoon, as a warm front continues to lift north.

As we progress into the overnight hours tonight into Wednesday morning, that’s when we’re most concerned for potential severe weather impacts to central Indiana.  Short-term, high resolution, modeling continues to suggest individual storms (perhaps super cells) will develop around midnight across the region.  These would include all modes of severe weather, including the potential of large hail and a tornado.

Finally, our severe weather threat will come to an end with the passage of a squall line during the pre-dawn hours Wednesday morning.  The biggest threat with this line of storms will be damaging wind, but a quick spin-up tornado can’t be ruled out either.

With the majority of this event occurring when most are sleeping, please have a way to get the latest information on watches and warnings that are sure to come tonight.  We highly encourage everyone to have a weather radio, and be sure to set the alert mode to “on” before bedtime tonight.

We’ll be back this evening with a fresh 7-day update!  Make it a great Tuesday!

Permanent link to this article: https://indywx.com/2017/02/28/active-severe-weather-night-ahead/

Unseasonably Warm And Stormy Weather Gives Way To Late Week Chill…

Monday evening is running much warmer than this time Sunday across most of the central, including right here in Indiana.

This warmer regime is the sign of stormy times that will develop as we move into Tuesday.  An initial round of showers and thunderstorms will impact central Indiana Tuesday morning and the HRRR forecast radar is picking up on this nicely, especially during the predawn hours.

The wet, stormy start to the day will give way to a mostly dry time of things through the majority of the daylight hours Tuesday, but our concentration will be on the Tuesday night-Wednesday morning period, as the potential exists for some rather turbulent weather.

We note the National Weather Service’s Storm Prediction Center outlines all of the region for the chance of severe weather Tuesday night and also note the possibility the “enhanced” risk area may expand in future updates.  Additionally, given some of the ingredients we’re observing this evening, there’s also the possibility we may see an upgrade to a “moderate” risk for portions of the region.  It’ll be particularly important to pay attention to weather updates Tuesday night.  Primary concerns are for large hail and damaging winds in a possible squall line that develops ahead of an approaching cold front.  Additionally, if storms develop ahead of the primary line of storms, the potential exists for a couple of tornadoes.  Have a means of getting the latest watches and warnings Tuesday night.

Modeled radar suggests things may begin to get “busy” around these parts late evening and during the overnight.  The latest high resolution NAM (hot off the press as of this update) paints a rather ominous look as midnight nears Wednesday morning.

We then note modeling bringing the squall line through central Indiana during the overnight and predawn hours.  We’ll have to fine tune timing as we move through the day Tuesday, but we bracket the hours of 2a and 6a when a concentrated line of strong to severe storms rumbles through the state (northwest to southeast).  Hail and damaging straight line winds are of greatest concern, but a quick spin-up tornado can’t be ruled out.

Our weather will turn quieter, but colder, as Wednesday progresses into Wednesday evening, including blustery conditions with falling temperatures.

A fast-moving clipper system will dive southeast Thursday evening into early Friday morning and this could produce a snow shower, or two, across the region, but shouldn’t amount to much from a snow perspective (keeping true to the tune of the winter, heh?).  The bigger story will be the “rude” feel to the air mass as we wrap up the work week, as highs only reach the upper 30s with a gusty wind.

That said, the chilly late week conditions won’t last long, and a gusty southwesterly air flow will develop as early as Saturday.  This will help give temperatures a significant boost Saturday afternoon after a cold start to the day.  60° is possible Saturday afternoon and the mercury may approach 70° Sunday!

More updates in the AM!  Have a great night, friends!

Permanent link to this article: https://indywx.com/2017/02/27/unseasonably-warm-and-stormy-weather-gives-way-to-late-week-chill/

Looking Ahead To Spring…

Meteorological spring begins in a few days (runs March through May).  We’ve already touched on the expected busy severe weather season and want to dedicate this post towards looking deeper into the weather pattern and the resulting precipitation and temperature impacts.

The latest longer-range data continues to be in very good agreement on the upper air pattern.  In short, the balance of the spring season looks to offer up a continued theme of warmer than average temperatures for our region.  (Not saying we won’t have to deal with a wintry “trick or two” over the first couple weeks of March).  When we look at spring, as a whole, we believe it’ll be one known more for the warmth and active, stormy times.

CFSv2 March Temperature Anomalies

CFSv2 April Temperature Anomalies

CFSv2 May Temperature Anomalies

JAMSTEC March through May Temperature Anomalies

The latest JMA monthly idea is one that has to raise an eye brow as it would paint an early summer across the Ohio Valley and Great Lakes.  Anomalous warmth (true summer-like air) would develop with a strong ridge over the Great Lakes and northeast.  This is something we’ll have to keep an eye on.  A big caveat here is how strong and quickly the coming El Nino develops.  It should be noted, El Nino years can feature some of the hottest air early, not late, in the summer season (relative to averages), and the JMA would, indeed, yield an early summer with such a look.

JMA May Forecast 500mb Pattern

It should also be noted modeling is suggesting a wet look, locally, especially during the early portions of spring.  The JAMSTEC and JMA are particularly bullish on a wet pattern.

JAMSTEC March through May Precipitation Anomalies

JMA March through May Precipitation Anomalies

The CFSv2 hits the wet March hard before a drier regime mid and late spring.

March Precipitation Anomalies

April Precipitation Anomalies

May Precipitation Anomalies

In closing, we seem to have a bit of a bumpy ride in front of us as meteorological spring begins.  While Old Man Winter hasn’t been seen much as of late, don’t be shocked if he makes his presence felt a few more times through the first half of March- both from a cold and snow perspective.  That said, data really points towards more of an overall warm regime developing the second half of the month, and continuing through the majority of spring, for that matter.  We’re keeping a close eye on May for an early summer-like feel to take hold, locally.  Subsequent JMA updates will be monitored closely.  We also remain confident of an active severe weather season.  Note the tendency of model data (above) to pull the mean trough position to the northwest March into April.  The clash of late-season wintry conditions west, combined with unseasonably warm temperatures across the east (not to mention the warmer than average Gulf of Mexico) likely will equal busy times as we progress through the spring severe weather season.

Permanent link to this article: https://indywx.com/2017/02/26/looking-ahead-to-spring/

Severe T-storms This Evening Give Way To Much Colder Air This Weekend…

Highlights:

  • Record warmth
  • Severe t-storm potential this evening
  • Scattered snow showers Saturday
  • Active pattern next week

Focused On Severe Weather This Evening…Though the day is beginning on a quiet note, we’re concerned it might not end that way, as strong to severe thunderstorms impact central Indiana this afternoon and evening.  The sunshine this morning is actually something that adds further concern for the potential of explosive thunderstorm development later today.  More specifically, we’re bracketing the hours of 4p and 10p for the likelihood of storms impacting central parts of the state (west to east), and some of these may become severe.  All modes of severe weather are in play today, including large hail, damaging winds, and a tornado or two.  Please have a means of getting the latest warning information and ensure you know your family’s severe plan.  Otherwise, we forecast to shatter the record high today as we zoom all the way into the middle 70s with a gusty southerly wind.

Winter will return with authority tonight and set-up a much colder weekend.  That high in the upper 40s Saturday will actually come at midnight with falling temperatures (most of the daytime hours will feature low-mid 30s with ‘chills in the 20s), windy conditions, and scattered snow showers.

A weak weather system is looking less and less impressive for the second half of the weekend, but we’ll continue to keep a chance of light rain in our forecast by evening.

Better rain chances will begin to ramp up Monday evening and become widespread Tuesday, including the possibility of thunderstorms, as well.  The second half of next week will trend colder…

Upcoming 7-Day Precipitation Forecast:

  • Snowfall: Trace
  • Rainfall: 0.50″ – 1.00″

Permanent link to this article: https://indywx.com/2017/02/24/severe-t-storms-this-evening-give-way-to-much-colder-air-this-weekend/

Looking At Friday’s Severe Set-Up…

An updated 7-day forecast will hit later today.  This morning we wanted to take the time to dig in a little deeper on Friday’s severe weather threat.

Severe Weather Outlook:

This morning the latest update from the National Weather Service Storm Prediction Center has expanded the ‘Enhanced Risk’ of severe weather Friday.  This includes all of central Indiana.

Summary:

A sub 1000 mb surface low pressure system will track northeast from northern MO (Friday morning) to central MI (Saturday morning).  Ahead of this, a warm front will lift north through central IN and into lower MI Friday afternoon.  A strong cold front will be located near the MS River Friday morning and barrel eastward, sweeping the state Friday night.

Unseasonably warm and moist air will be drawn northward and encompass the entire region Friday.  Forecast highs should break records tomorrow and be in the lower-middle 70s for most of the region (thinking we see plentiful sunshine during the daytime hours).  Dew points will near 60°. Considering this is late February, those are impressive ingredients coming into play.  The added sunshine tomorrow is actually a bad thing as it will add “fuel to the fire,” so to speak, and help play a role in potentially explosive thunderstorm development Friday evening.

Forecast dew points will reach around 60 degrees across the region Friday afternoon.

Surface-based CAPE (Convective Available Potential Energy) is modeled to reach between 1200-1600 J/kg Friday evening across the region.

Threats and Timing:

Most of Friday is going to be quiet, but it’s as we move into Friday afternoon and evening that we’ll need to keep close eyes to the sky and radar.  The potential exists for individual super cells to develop out ahead of an eastward-advancing line of thunderstorms Friday evening.  All modes of severe weather are possible Friday evening, including large hail, damaging winds, and tornadoes.  As of now, we bracket the hours of 4p and 10p for the period where severe weather may be impacting portions of central IN.

As mentioned yesterday, we highly recommend reviewing your family’s severe weather safety plan and ensure weather radios are charged with warning modes “on” Friday.

Permanent link to this article: https://indywx.com/2017/02/23/looking-at-fridays-severe-set-up/

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