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Which website do you think is the most accurate for a 7-day forecast?
I'm finding that when I check 7 days out, the websites are radically different. It's most important that we are aware of the weather ahead of us when we leave New England to drive to NC, using the 95S to 287S to 78W to 81S to 66E back to 95S route.
Been using Weather.gov and AccuWeather, occasionally WeatherUnderground. Interesting that all 3 can be different!!!
Which website do you think is the most accurate for a 7-day forecast?
I'm finding that when I check 7 days out, the websites are radically different. It's most important that we are aware of the weather ahead of us when we leave New England to drive to NC, using the 95S to 287S to 78W to 81S to 66E back to 95S route.
Been using Weather.gov and AccuWeather, occasionally WeatherUnderground. Interesting that all 3 can be different!!!
I might sound like a broken record to those who heard me say this but. .. Once you realize what and how forecasts are made you'll realize why they are very different at times (especially past 3 days!).
Every single forecast you see from 1hr from now to 7 days from now, from local meteorologists to big outlet sources is from weather models.
Sometimes the source has their own model, most times the sources blend models together. Sometimes more accurate than others, other times less accurate.
I used to think someone was behind the forecasts typing it out for my town.. lol. Then I realized that would be impossible to do for millions of cities across the nation. So it's computer generated and uses all kinds of algorithms and models to put out a forecast.
So I hope that helps at least understand why forecasts you see are different. It's the future. Nobody knows an exact. All we can do is use technology and tools available to make a better guess.
Are you familiar with where to get your local NWS Office forecast discussions? A lot of times you will see them reference the models.
This is for your area which NWS Boston (Taunton) covers. Notice they are making a forecast based on what the models are showing.
Quote:
NATIONAL WEATHER SERVICE TAUNTON MA
700 AM EST SAT FEB 28 2015
PTYPE WILL PROBABLY BE ALL SNOW FOR A LOT OF THE REGION. IT BECOMES
MORE UNCERTAIN ACROSS SOUTHERN RI AND FAR SOUTHEAST MA. THE NAM
MODEL IS AN OUTLIER AND MOST AGGRESSIVE IN BRINGING A SURGE OF WARM
MID LEVEL AIR NORTHWARD...WHICH WOULD CHANGE PTYPE TO RAIN FOR JUST
ABOUT ALL OF RHODE ISLAND AND SOUTHEAST MA SUN NIGHT.
HOWEVER...MOST OF THE OTHER GUIDANCE KEEPS PTYPE SNOW EXCEPT FOR
AREAS NEAR THE SOUTH COAST/CAPE/ISLANDS. SO FOR NOW WILL KEEP THE
CHANGE OVER LINE JUST SOUTH OF THE TAUNTON TO PROVIDENCE
CORRIDOR...BUT THIS MAY NEED TO BE ADJUSTED BASED ON LATEST MODEL
DATA.
TUE NIGHT INTO THU... MODEL CONSENSUS IS NOW GENERALLY IN AGREEMENT THAT BOTH THE NRN
AND SRN STREAMS PHASE IN SOME FASHION ACROSS THE CENTRAL CONUS
WITH THE FORMATION OF LOW PRES WHICH IS EXPECTED TO SLIDE ACROSS
SRN CANADA.
Then sometimes they will change the forecast like this morning because current OBS showing something different then models had overnight.
7 AM UPDATE...
UPDATED TEMPS AND DWPTS TO BRING THEM UP TO CURRENT TRENDS. A LOT
OF VARIABILITY WITH RADIATIONAL COOLING.
I understand that it's just a "forecast" and it's based on models, was wondering which one overall is more often correct than not.
Perhaps, it's just a question that can't really be answered. I like to tie up loose ends and ya just can't do that with weather, especially New England and especially with a winter like this one.
Thanks for taking the time to explain how the forecasts are created, we'll just have to keep a watchful eye.
I used to think someone was behind the forecasts typing it out for my town.. lol. Then I realized that would be impossible to do for millions of cities across the nation. So it's computer generated and uses all kinds of algorithms and models to put out a forecast.
Hmm. I thought it was a bit more than that. The meteorologists at the local office (for me NWS Boston at Taunton) puts out a general forecast and a computer algothithm takes their forecast to produces and individual point forecast for any place in the area. The local forecast office is most obvious when looking at snowfall graphics: sometimes there's a jump in snowfall prediction when going to a different NWS office.
The one habit I've noticed from NWS forecasts is they tend to be conservative: any extreme model prediction (such as unusual cold or a big snow or rain event) the forecast will put out a less extreme version of low probabilities until it gets close. Weatherunderground adopts model output of events 5+ days out faster and estimates snow amounts. I often give it a glance even though I don't always trust it; it gives a good indication if something big might happen.
was wondering which one overall is more often correct than not.
Perhaps, it's just a question that can't really be answered.
Not sure there are skill scores or hardcore tracking to know who's more accurate but I would Just use NWS site. Enter city & state on the left. Like nei says they are a bit too conservative but at least they are reputable. AND they will update multiple times a day. Not sure about those other sites.
Now... if you wanted to keep score and keep track just for a month or so to see who's "more" accurate out there, please report back to us, we'll be curious at the findings. It's very time consuming and needs to be compared multiple times a day since they change throughout the day.
Quote:
Originally Posted by nei
Hmm. I thought it was a bit more than that. The meteorologists at the local office (for me NWS Boston at Taunton) puts out a general forecast and a computer algothithm takes their forecast to produces and individual point forecast for any place in the area. The local forecast office is most obvious when looking at snowfall graphics: sometimes there's a jump in snowfall prediction when going to a different NWS office.
Yeah, for the main climo site I'm sure there's more a "personal" touch to it and of course local meteos and their TV's putting out a forecast but still based on the models of course. But just imagine the sites like TWC, NWS, WU, Accu, ect ect having someone physically put together a forecast for every single city you enter.... They would need to hire a lot more folks. LOL
Yup, of course the snow and precip forecast maps are physically done..
-----------------------
Speaking of daily changes... Check out what NWS NY put today
Quote:
NATIONAL WEATHER SERVICE NEW YORK NY
1257 PM EST SAT FEB 28 2015
.NEAR TERM /THROUGH TONIGHT/...
12Z KALY AND KOKX SOUNDINGS AS WELL AS 12Z BUFKIT DATA SUGGEST MIXING TO AROUND 950 HPA THIS AFTERNOON. BASED ON THIS LOWERED HIGHS A COUPLE OF DEGREES. REMAINDER OF FORECAST REMAINS ON TRACK.
So the 12z balloon launch this morning revealed more mixing in the atmosphere than models had shown, so they had to lower their max temps they had for today. Case in point... forecasts even for same day can be off.
The answer is none. There isn't a single forecast that is highly accurate 7 days out. They all have a hard time just 4 days out.
Yup.
I had a passion for weather since I was 7yrs old in the 1980s writing down current OBS. Been looking at forecasts since and always wondered why they were always off.. Now it's just more fun to look at models or simply out the window. lol Once in a while I'll still glance at the forecasts out there but I never ever and I learned not to use the details as gospel..
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