Tuesday Morning Rambles: Potential Tropical Impacts Down The Road And Renewed Heatwave Claim Headlines…

I. Another quiet, pleasant mid-summer day is on tap thanks to high pressure. Though very warm, humidity will remain low today. We should add another 90 degree day to the books later this afternoon.

II. A cold front will move into the Ohio Valley Wednesday and we expect a couple of lines of thunderstorms to move across central Indiana during the day. The first line will likely be in a weakening state as it approaches central Indiana around lunchtime tomorrow, however, we expect a second line of showers and t-storms to move through the heart of the state tomorrow evening.

The Storm Prediction Center includes northwest IN in a ‘Slight’ risk of severe weather Wednesday.

III. While dry conditions (and cooler temperatures) will return here for late week and into the first half of the weekend, all eyes by this time will be centered on soon-to-be Barry. Conditions still seem favorable (sea surface temperatures and upper level wind environment) for a disturbance currently over SW GA to strengthen into a named tropical system over the northern Gulf over the next 24-48 hours.

While confidence remains low concerning potential inland impacts from the eventual remnants of Barry (always the case with tropical systems), there seems to be an opportunity for two paths as of now.

“Path A” would essentially be a scenario where Barry gets trapped under an upper level ridge to the north, resulting in raining himself out over Texas next week. “Path B” would curl Barry north and northeast into the OHV, spreading a swath of heavy tropical rains well inland. Stay tuned.

IV. The other headliner will be a return of significant heat next week. While Barry may (or may not) have a say in cooling us down late next week, there will be a renewed stretch of 90 degree warmth that develops Sunday into at least the middle of next week. Longer range data continues to trend hotter and we’ll have a look at the updated European Weeklies later today or Wednesday.

Bill McMillan July 9, 2019 No Comments Client, Forecast Discussion, Forecast Models, Heavy Rain, Long Range Discussion, Tropics, Unseasonably Warm, Weather Rambles

VIDEO: Tuesday Evening Rambles…

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Bill McMillan May 21, 2019 No Comments Client, Ensemble Discussion, Forecast Discussion, Forecast Models, Indy 500, Long Range Discussion, Memorial Day weekend, MJO, Plant '19, Rain, Severe Weather, Spring, Summer, T-storms, Unseasonably Cool Weather, Unseasonably Warm, Weather Rambles, Weather Videos

“Transition” Is The Name Of The Game…

As we look ahead to late-May and early June, “transition” is the word that comes to mind when describing the overall weather pattern.

We’re going to begin pulling out of this unseasonably chilly pattern late-week and we’ll replace it with a true summer-like regime. Note the differences at 500mb between now and this weekend:

Not only will the 80s return, but oppressive dew points can be expected as well by Friday (65-70 degrees). The sweat factor will be back in full effect!

With that said, there’s reason for concern that the flip to summer may not last.

Not only do we continue to see high-latitude blocking in place, but the MJO is showing signs of rotating into Phase 1 as we inch closer to early-June. That Phase 1 this time of year is a cool one for the eastern portion of the country. Note the tendency for eastern troughiness illustrated in Image 2 below.

Perhaps ensemble data is seeing this cooler transition in the pattern on today’s 12z run:

Bottom line, confidence is high on a summer-like flip as we welcome in the weekend, continuing into early parts of Week 2, but we don’t think it’s a “stick and hold” variety of warmth. There’s growing reason to believe a flip back to cooler conditions looms before we close out the month.

Bill McMillan May 13, 2019 No Comments Client, Ensemble Discussion, Forecast Discussion, Forecast Models, MJO, Plant '19, Spring, Summer, Unseasonably Cool Weather, Unseasonably Warm, Weather Rambles

Tuesday Afternoon Rambles: Weekend Model Differences; What’s Beyond The Cooler Mid-May Shift?

I. A couple widely scattered light showers have flared up this afternoon, but most central Indiana neighborhoods have enjoyed dry conditions with sunshine and temperatures in the mid-upper 70s. Look for more of the same Wednesday, including filtered sunshine through a good chunk of the day. Warm Air Advection (WAA) will help boost temperatures into the lower 80s for most of the immediate area.

II. Better aerial coverage of showers and thunderstorms will develop late Wednesday night into Thursday night. We believe 3 rounds of showers and storms are possible during this time frame (at least impacting portions of the central Indiana viewing area):

Late Wednesday night into the predawn Thursday
Thursday afternoon
Thursday evening as the cold front sweeps through the state

III. High pressure will build into the region as we close the week. This will lead to improving weather conditions, including increasing sunshine. A very nice close to the work week/ open to the weekend is dialed up! Make those patio plans now!

IV. Modeling differs on the handling of our weekend weather feature(s). The GFS (image 1) maintains the idea of a dry Saturday, followed by showers Sunday as a cold front sweeps through the region. Moisture would be limited with such a solution. The European (image 2), however, is more bullish on a more widespread rain event arriving Saturday PM into Sunday AM. Stay tuned as we work to reach some sort of agreement between the data.

V. After a cooler than normal period of weather through the middle of the month, we’re thinking the coolest anomalies will pull back into the intermountain west and 4-Corners region. Do we foresee any major late-May heat? No, but we should moderate against the norms during the last week to 10 days of the month.

After a drier stretch of weather through the mid-May period, precipitation should return to at least average levels through the late month stretch. Early indications would then suggest wetter than normal times return as we get set to open June…

Bill McMillan May 7, 2019 No Comments Client, Forecast Discussion, Forecast Models, Heavy Rain, Plant '19, Rain, Spring, T-storms, Unseasonably Cool Weather, Unseasonably Warm, Weather Rambles

Pattern Returns To An Active Time Of Things…

One word to describe the mid-April weather pattern? ACTIVE. Tonight’s medium and long range video update dives in further…