Category: Severe Weather

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/

Active Pattern Ramping Up; Monitoring Multiple Storm Chances…

Highlights:

  • Spring-like air continues
  • Severe t-storm potential Friday PM
  • Much colder weekend
  • Another round of strong-severe storms next week?

Buckle Up For A Wild Ride…Morning fog (some very dense, especially north of the city) will burn off and give way to increasing sunshine today, along with unseasonably warm temperatures.  In fact, we’ll be near-record territory (Indy’s record high today is 70° and we forecast to tie that record this afternoon).  We’ll remain near record territory over the next couple of days, but our attention will, unfortunately, have to shift from the record warmth to strong-severe thunderstorm potential.

Most of Thursday will be dry, but a few scattered showers will likely dot the central IN landscape by the evening hours.  Similar to Thursday, most of the day Friday will also be dry.  It’s not until we head into Friday evening and night that we’re concerned for thunderstorms tracking through the state.  A few of these storms will likely reach severe levels.  Large hail and damaging winds are of greatest concern with the severe thunderstorms that develop.  The cold front will sweep the state Friday night and a midnight high Saturday morning in the upper 40s will crash (most of the daytime will feature temperatures in the 30s with wind chills in the 20s) and wind-whipped snow flurries can be expected.

A weak weather system is still expected late Sunday and could feature a light rain and snow mix (not a big deal).  What will be a bigger deal is a much stronger storm system rolling through the Mid West early next week.  Unfortunately, another round of strong to severe thunderstorms will be possible Tuesday…

Upcoming 7-Day Precipitation Forecast:

  • Snowfall: Trace
  • Rainfall: 1.00″ – 1.50″

Permanent link to this article: https://indywx.com/2017/02/22/active-pattern-ramping-up-monitoring-multiple-storm-chances/

Incredible February Warmth Continues Until This Weekend…

Highlights:

  • Unseasonably warm conditions continue
  • Strong-severe t-storm potential Friday PM
  • Much colder this weekend

Spring-Like Weather Continues…A weak weather system will create the chance of showers into this afternoon, but many more dry hours can be expected than wet.  In fact, some neighborhoods won’t even see a drop of rain today.  The bigger news?  A continuation of unseasonably warm, April-like, temperatures.  In fact, we’ll turn even warmer for the second half of the work week and get back to dry time Wednesday and most of Thursday.

A strong cold front will sweep through the state Friday night.  Ahead of this front, shower and thunderstorm coverage will increase Friday afternoon into the evening hours.  Some of these storms may become strong to severe and include damaging straight line winds and hail.

We’ll then turn much colder Friday night and that will set the stage for a more seasonable weekend.  Snow flurries may fly in the blustery northwest flow Saturday.  A fast-moving weather maker will then spread a mixture of rain and wet snow across the state Sunday evening into early Monday.  Confidence is low on timing of this late weekend system and fine tuning will be required moving forward.

Upcoming 7-Day Precipitation Forecast:

  • Snowfall: Trace – Dusting
  • Rainfall: 0.25″ – 0.75″

Permanent link to this article: https://indywx.com/2017/02/21/incredible-february-warmth-continues-until-this-weekend/

Spring-Like Now, But Winter Returns This Weekend…

Highlights:

  • Dense morning fog
  • Tuesday showers
  • Severe potential Friday
  • Much colder this weekend

Two Seasons This Week…We’re starting the work week with dense fog across central Indiana.  This will eventually burn off to a variably cloudy sky by afternoon, along with continued unseasonably warm temperatures.

A weak weather system will press through the state Tuesday and this will help lead to a period of showers Tuesday morning into the early afternoon hours.  This won’t be a big event (most neighborhoods should accumulate between 0.10″-0.25″ of rain), but plan to pack the rain gear as you leave the house Tuesday morning.

A much stronger storm system will impact the region Thursday into Friday.  As strong low pressure passes by to our northwest it’ll help pull anomalously warm, moist air northward Friday.  Strong to severe thunderstorms may occur along the strong cold front that will pass late Friday.  While we still have time to “fine tune” details on timing, early thinking would place greatest emphasis on large hail and damaging wind potential.  Stay tuned.

Much colder air will hit with authority Friday night and set-up a wintry weekend.  The spring-like feel of this past weekend will be all but a distant memory and flurries may fly Saturday morning in the colder, blustery air.

Upcoming 7-Day Precipitation Forecast:

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

Permanent link to this article: https://indywx.com/2017/02/20/spring-like-now-but-winter-returns-this-weekend/

Sunday Morning Rambles: Focusing On Severe Weather…

Low clouds and areas of fog will be slow to burn off this morning, but the sunshine should eventually return later this afternoon and evening, providing a phenomenal close to the weekend.

Despite the lack of sunshine this morning, temperatures continue to run much milder than average.  We’re currently running nearly 20° above where we should be at the 9a hour.

A quiet start to the work week is ahead as high pressure dominates early on.  That said, a weak storm system will scoot through the state Monday night and Tuesday morning and this will help offer up the chance of showers and perhaps a rumble of thunder.

The next (more significant) storm system will pose a severe weather risk to close the week.  We continue to keep a close eye on Friday and the Storm Prediction Center is as well, with western IL, IN, and western KY in their Day 6 Outlook.  It’s still early, but the primary focus with the severe potential this storm may pose will be large hail and damaging straight line winds.  Stay tuned as we continue to analyze the latest data.

We’ll turn sharply colder Friday night and Saturday.  Though it’ll feel much colder, we’ll really only “chill” to seasonal levels, including a gusty northwesterly breeze Saturday.

Longer-term, we’re rumbling into a much more active weather pattern through the mid range period.  As the mean trough sets-up position in the west, the ridge will flex it’s muscle across the east yet again during early portions of Week 2.  This will set the stage for a repeat of what we deal with Friday and, accordingly, we’ll have to monitor early next week for portions of severe weather yet again.

Permanent link to this article: https://indywx.com/2017/02/19/sunday-morning-rambles-focusing-on-severe-weather/

Awesome Weekend Weather Continues; Changes Ahead Next Week…

Highlights:

  • Spring-like weather rolls along
  • Shower chances return
  • Strong t-storm potential
  • Different tune next weekend

Is This February?  Our stretch of unseasonably pleasant, spring-like, weather will continue for the second half of the weekend and as we progress into the early stages of the work week.  Find a way to get outside the next couple of days (that’s an order ;-)).

A weak weather system will scoot through here Tuesday and serve to increase our cloud cover, along with a few scattered showers.  Dry conditions return Wednesday, but by then all eyes will be on an approaching stronger storm system that will provide increased shower coverage by Thursday and strong to severe thunderstorm potential Friday.  Speaking of severe weather, we think this spring will offer up a busy severe weather season.  We’ll have additional updates on the severe potential as time gets closer, but just keep a mental note Friday could be a busy weather day.

We’ll abruptly transition back to winter Friday night and the air will grow cold enough a week from today to allow scattered snow showers to fly in a gusty northwesterly breeze next Saturday.

Upcoming 7-Day Precipitation Forecast:

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

Permanent link to this article: https://indywx.com/2017/02/18/awesome-weekend-weather-continues-changes-ahead-next-week/

Thoughts Shift Towards Severe Weather Season…

With the unseasonable warmth this week, our thoughts begin to shift to the coming spring months ahead.  Of course with spring comes the potential of storms- some of which include severe weather outbreaks.

Already, 2017 has wasted no time in the tornado department, year-to-date- more than double the (10) year average across the United States.

The Gulf of Mexico is boiling warm (running 1°-3° C above normal) and this will aid in transporting moisture-rich air north.  As storms eject out of the Rockies and Plains, one would tend to believe anomalously warm dew points and precipitable water values will be available.

The JMA Weeklies show an active stretch developing as we progress through the next few weeks.

As we rumble deeper into the spring months, the mean trough position should be located across the west.  The end result should be a mean storm track that runs into the Ohio Valley- courtesy of resistance from an eastern ridge (that warm water in the Gulf and East Coast screams the mean ridge position should be located across the east coast).  Confidence is greater than normal on a busy severe weather season.

Much more later as spring evolves.

Permanent link to this article: https://indywx.com/2017/02/18/thoughts-shift-towards-severe-weather-season/

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