Sunday Morning Weather Rambles…

1. August has gotten off to a cool start through the first eight days and we expect this to continue during the upcoming week, only growing cooler, relative to the…

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Pick Of The Weekend Is Today; Taste Of Early Fall Coming…

Screen Shot 2015-08-08 at 9.21.27 AMHighlights:

  • Half-n-half weekend
  • Early week storms
  • Fall preview coming

The weekend is off to a pleasant start- both from a temperature and humidity perspective, but also with current sky conditions across the area.  Expect periods of mid and high level cloudiness to increase later today.  We also note some of our shorter term modeling trying to push light rain into the picture by evening, but think the air mass will take some time to moisten up before we see much in the way of rain.  Most of this should dissipate moving into western IN this evening.

The second half of the weekend will provide much better chances of showers and embedded thunder.  In fact, we expect a couple waves of showers and thunderstorms Sunday.  It won’t rain the entire time, but keep the umbrella and rain gear handy.  Thunderstorm chances will continue as we open the new work week before a big push of cooler and drier air engulfs the region heading into mid week.  An early fall preview will settle in Tuesday evening and have things feeling mighty nice around these parts for the rest of the week.

Upcoming 7-Day Rainfall Forecast: 0.50″ – 1.00″

Weather Rambles To Wrap Up The Work Week…

   1.) The high resolution NAM has been consistent on trying to deliver a skinny line of showers and thunderstorms into central Indiana Friday evening. We’ll keep an eye on…

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August Outlook

Before we dive into what we expect for the month of August, here’s a look at where we stand so far for July (with 4 days left as of this post).

This was our July forecast upper air pattern, issued 6.29:

July2015UAHere’s a look at temperature anomalies through 7.27:

ncep_cfsr_noram_t2m_anomWhile overnight lows have been running warm with all of the clouds and moisture, daytime highs have been significantly below average:

tmax30dydevWith four days left in the month, it’s already been the wettest month on record at IND.  The Corn Belt, as a whole, has been quite wet month-to-date.

nws_precip_conus2_mtd nws_precip_indy_mtd precip30dydevAs we progress into August (where does time go) we think we continue in an active pattern, locally, biased cooler than normal and wetter than normal.

AugustUA2015While modeling disagrees with the specifics in regards to the timing, most mid to long range modeling does agree on the overall idea of the hot dome (ridge) backing west and setting up shop over the southwest portion of the country early August which will put our region in (you guessed it) the favorable northwest flow for active weather.  Similar to July, disturbances will ride the periphery of the hot dome to our southwest and offer up plenty of chances for showers and thunderstorms.  That’s not to say we’re looking at setting another record for greatest amount of rain within a month, but it is saying precipitation should be above average yet again.

From time to time the ridge will attempt to expand northeast, but we don’t think it’s potentially until the last portion of the month before the ridge has much chance to encompass our region for any staying power more than a few days.  We suggest getting used to this 500mb look:

EarlyAugThe latest NAEFS and CFSv2 highlights the cooler than normal period we should undergo early August (especially after the 5th).

wk1.wk2_20150726.NAsfcT2015072712_054@007_E1_north@america_I_NAEFS@TEMPERATURE_anomaly@probability@combined@week2_186The latest European Weeklies suggest there may be a window for a “calmer” regime after the 25th.  That said, it’s a rather volatile pattern.

Yet another tool we’ve been keeping a close eye on the past few months has been the SOI (Southern Oscillation Index) as it’s been a big help in tipping us off for prolonged wet weather.  Note the consistent negative SOI:

Screen Shot 2015-07-27 at 11.22.11 PM

 

 

 

 

 

 

World

Not to sound like a broken record, but we continue to think the relentless wet weather pattern “keeps on keepin’ on” as we progress through August.  It’s very interesting to note the dynamics at play between the strengthening El Nino and warm northeast PAC waters… More on that, and the implications we feel for fall and winter, in the weeks and months ahead. 🙂

July2015SST