Category: GFS

Oct 23

Rain Chances Going Up This Weekend; Taste Of Winter Blows Into Town Before Halloween…

Dry weather will prevail today and the majority of Thursday across central Indiana (a light passing shower is possible across northern Indiana, but this won’t be a big deal).

Scattered light showers are possible Thursday night into the day Friday, along with an increase in cloud cover, but again, significantly more dry time is anticipated than wet. Some won’t see a drop of rain Friday.

A scattered light shower is possible Thursday night-Friday across central IN.

As we rumble into the weekend, a vigorous upper level low in Oklahoma will “bowl” east across Arkansas and then shoot northeast across the Ohio Valley Saturday into Sunday. (Hint, you may want to get used to this kind of storm track over the upcoming winter). This will result in increasing aerial coverage of rain Saturday.

Rain will exit off to the northeast Saturday night and a drier second half of the weekend is expected. By the time all is said and done, a solid 0.50″ to 1″ of rain is expected (we’re currently siding with a blend of the aggressive European and lighter GFS).

After a wet 1st half of the weekend, all eyes will be set on a taste of winter that’s dialed up just before Halloween. A cold front will blow through the Ohio Valley early next week with the threat of rain followed by sharply colder air. As upper level energy rounds the base of the digging significant trough, the first flakes of the season can be expected across the region before Halloween (still will have to fine tune timing). This pattern will also serve up the first accumulating lake effect snow event of the season, including the Snow Belt regions of IN, MI, and OH.

A winter-like feel can be expected as we close October and open November.

Permanent link to this article: https://indywx.com/2019/10/23/rain-chances-going-up-this-weekend-taste-of-winter-blows-into-town-before-halloween/

Oct 10

Cool 6-10 Day Period Ahead, But Then What?

A strong cold front will sweep through the area tomorrow and help usher in the coolest air so far this autumn. This will set the tone, combined with the recurving WPAC typhoon, for a chilly upcoming 6-10 day period, but what lies beyond this period later in the month?

Recurving Super Typhoon Hagibis will promote reinforcing chill across our area next week.

We turn to a couple of our more trusted teleconnections for advice.

Note the PNA “bobbing” up and down through the medium range period, with more of a negative look around the 20th. This argues for a milder stretch of weather around that time. (Further out, we’ll keep close eyes on the PNA to see if a more consistent positive signal develops as we inch closer to November).

The EPO pops strongly positive mid month which, too, argues for milder times, locally. That said, similar to the PNA above, the EPO is trending towards a scenario that would present colder times as we rumble towards November. We’ll monitor for consistency.

To no surprise, given the two primary teleconnection drivers above (remember these can change as the seasons evolve), we see the pattern set to turn milder just beyond Day 10. Note the strong agreement between the European, Canadian, and GFS ensemble data below.

Permanent link to this article: https://indywx.com/2019/10/10/cool-6-10-day-period-ahead-but-then-what/

Sep 30

Evening VIDEO: Much Cooler Changes On The Horizon; Early Week 2 Storm?

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Permanent link to this article: https://indywx.com/2019/09/30/evening-video-much-cooler-changes-on-the-horizon-early-week-2-storm/

Jul 17

“Sneaky” Storms Precede Dangerous Heat…

As we prepare for the hottest air of the summer, we’ll have to remain on guard for the potential of thunderstorms impacting at least a part of the state Thursday morning.

Upper level energy will track southeast into the state late tonight and early Thursday and combine with just enough energy to allow thunderstorms that should develop during the overnight (across southern WI and northern IL) to track into western Indiana during the predawn hours. (It should be pointed out this is separate from the convection that is currently resulting in warnings across MO and IL- as of 6:20p eastern time). Thereafter, these storms are expected to rumble into central Indiana in a weakening format around the morning rush Thursday.

Upper level energy will likely result in a weakening complex of storms pushing into central IN Thursday morning.
Forecast radar at 8a Thursday.

Thereafter, the big story will be the high heat and humidity that will lead to truly dangerous conditions across central Indiana beginning tomorrow afternoon into Sunday. Heat indices will top out between 100-105 each afternoon and in some cases a few degrees higher. It’ll be important to build in frequent breaks inside and drink plenty of water. Most, if not all, neighborhoods can expect to remain rain-free through the first half of the weekend (after we deal with our Thursday morning storms).

Thankfully, we still are forecasting a “game changer” of a cold front to plow through the region late Sunday and early Monday with storms (a few could be severe) followed by a much cooler and more refreshing air mass next week.

This is likely the first of a couple of cold fronts that will pass through the region between now and the end of the month, ensuring we wrap up July seasonal to cooler than average.

Permanent link to this article: https://indywx.com/2019/07/17/sneaky-storms-precede-dangerous-heat/

Jul 09

VIDEO: Strong Storm Threat NW Tomorrow; Where Will Soon-To-Be Barry’s Remnants Track Next Week?

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Permanent link to this article: https://indywx.com/2019/07/09/video-strong-storm-threat-nw-tomorrow-where-will-soon-to-be-barrys-remnants-track-next-week/

Jul 07

Getting To Be That Time Of Year: Major Model Differences Around Tropical Mischief…

A trough of low pressure will continue moving south through the Southeast region (now) and into the northern Gulf (by the early to middle portion of the work week).

With warmer than average sea surface temperatures across the north-central and northeastern Gulf, along with a favorable upper level wind environment, the potential is present for this disturbed area of weather to strengthen into a tropical depression over the next few days before meandering just off the coastline.


While Gulf Coast beach-goers will need to remain on guard for the threat of more organized unsettled weather during the upcoming period centered on early to mid week, the potential inland impacts are much less certain at this point.

Reviewing the latest midday model guidance shows two different camps:

I. The GFS likes the idea of a heavy inland rain threat impacting the Carolinas (primarily east of the Appalachians) late week and into the weekend.

II. The European forecast model “curls” the area of disturbed weather west. A polar opposite of the GFS solution, the European strengthens the system across the north-central Gulf before bringing potential Barry into LA over the weekend. Thereafter, if this solution proves correct, portions of the OHV (including central Indiana) would deal with rain early next week.

We, obviously, have a long way to go with this set-up, but given the overall upper air pattern we tend to favor more of a GFS solution at this point in time. Needless to say, we’ll keep a very close eye on things over the upcoming few days…

Permanent link to this article: https://indywx.com/2019/07/07/getting-to-be-that-time-of-year-major-model-differences-around-tropical-mischief/

May 22

Prolonged Unsettled Stretch Of Weather…

Yesterday was only the beginning of a renewed prolonged stretch of unsettled and stormy weather. A series of fronts will make a move towards the OHV only to stall out and lift north back as a warm front over the upcoming 7-day period. The end result? An extended stretch of wet, stormy conditions.

Rainfall amounts will run above normal over the upcoming 7-day period.

Get used to the setup above with a stalled front nearby and waves of low pressure moving along the associated boundaries from time to time. As these ripples of energy scoot along the front, more enhanced showers and thunderstorms can be expected.

It’s still tough from this distance to say with certainty which day(s) will offer up the most widespread shower and thunderstorm coverage in this pattern, but we continue to lean towards Saturday into Sunday. Stay tuned.

Models agree on widespread 1.5″ to 2.5″ rainfall totals over the upcoming week with locally heavier amounts.

Conditions will also return to a warmer than normal theme into the middle of next week. At times, conditions will become oppressive (depending on which side of the front you find yourself on). If heading to the track, ensure you have means to remain cool and pack the rain gear just to be safe!

More later tonight on the long range, including a video recap of our Summer Outlook.

Permanent link to this article: https://indywx.com/2019/05/22/prolonged-unsettled-stretch-of-weather/

May 06

All-Access Video: Timing Out Storm Chances This Week; May Takes On A Cooler Feel…

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May 05

All-Access Video: Week-Ahead Outlook; Cooler Than Average Pattern On Deck As May Progresses…

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Permanent link to this article: https://indywx.com/2019/05/05/all-access-video-week-ahead-outlook-cooler-than-average-pattern-on-deck-as-may-progresses/

Mar 07

Long Range Video Update: Changeable Pattern For The 2nd Half Of March Into April…

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