September Medium/ Long Range

[Weather Will]

Latest WB EURO weeklies for September.  Looks like more perfect fall weather, although we need rain.

[Weather Will]

Pretty sparse late week rain  chances on the WB 12Z globals.

[Jebman]

Look I apologize for posting this stuff in the modeling long range thread. But I need a real meteorologist like Millville Wx, high risk, WxUSAF,  wxmeddler, or any other red tagged Met to explain this nomenclature to me.

My fields are software engineering and AI engineering, not these apparently statistical terms. I am not really a weather person, only a silly snow weenie in winter wishing 4 feet of snow on DCA from one storm.

This paragraph is from today's AFD for AUS.

The rainy and cloudy weather will support cooler temperatures
beginning this weekend. With a thermal trough in our area during
this period, showers and storms could be more effective at producing
rain-cooled air. The approaching front may also contribute some
cooler air depending how far south it gets, though given the time of
year, most of the cooler temperatures will probably be rain and
cloud driven. This introduces significant uncertainty in
temperatures as illustrated by 7 to 10 degree interquartile ranges
in NBM QMD maximum temperatures on Sunday and Monday. Given the
large uncertainties, the current temperature forecast is aligned
with the NBM, featuring highs in the 80s to low 90s Sunday and
Monday before gradually warming back up into midweek after the
active weather pattern passes.

 

What I would like a meteorologist to do for me here is to please explain to me in 4th grade terms, what interquartile means. This stuff is WAY above my paygrade as well as centuries above my IQ level too. lmao

 

Thanks in advance, I am sorry for posting this in the long range thread BUT I need a real Met to try and explain this term to me.

Another thing, what are standard deviations? What do meteorologists mean when they say in an area forecast disco, that moisture is several standard deviations above normal for that time of year?

 

Might have to send someone some XRP for defining INTERQUARTILE. And standard deviation.

This time next year, xrp is going to be at least 75 dollars a coin. Right now it is about 2.30 I think. It's gonna go up. By 2030 it is gonnabe about 650 a coin.

 

[Weather Will]

If you did not get rain today, no wet weather in sight over the next week. WB 18Z EPS:

[CAPE]

Mostly dry but also normal to below normal temps through mid month. Longwave pattern supports surface HP to our NW/N/NE throughout.

[frd]

Late month warm up seems to be a possiblity.

Not unusual in Septembers that feature cool shots such as this month based on medium range modeling. 

 

[mitchnick]

15 hours ago, frd said:

Late month warm up seems to be a possiblity.

Not unusual in Septembers that feature cool shots such as this month based on medium range modeling. 

 

The regular Eps has been too warm at range since the start of August while the AI version has been better. Maybe the trend continues and maybe not. Either way, until and unless the regular Eps can prevail, I wouldn't be too concerned with that map. Otoh, even if right, we're real close to the +.50-+1.0C line, so a couple degrees F isn't a scorcher.

[Rhino16]

On 9/4/2025 at 1:40 PM, Jebman said:

Look I apologize for posting this stuff in the modeling long range thread. But I need a real meteorologist like Millville Wx, high risk, WxUSAF,  wxmeddler, or any other red tagged Met to explain this nomenclature to me.

This introduces significant uncertainty in temperatures as illustrated by 7 to 10 degree interquartile ranges in NBM QMD maximum temperatures on Sunday and Monday. What I would like a meteorologist to do for me here is to please explain to me in 4th grade terms, what interquartile means. This stuff is WAY above my paygrade as well as centuries above my IQ level too. lmao

 

Basically, we can take a set of numbers and break them into quarters. Just like we do with the months in a year. 

Interquartile is the set of numbers between Q1 and Q3, the numbers in the middle of the dataset. So if the models are putting out numbers that are very spread out and uncertain like in your example, the Interquartile Range will be high. If the models are all putting out similar numbers, the difference between Q3 and Q1 will be low, so making a temperature forecast might be easier.