Category: GFS

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.

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Sep 30

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

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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.

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Jul 09

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

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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…

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