The Washington Post has an excellent meteorologic team, called the "Weather Gang". Like essentially all forecasters in the DC area they went way overboard in their predictions for yesterday's non-storm. This morning they published an excellent analysis (I have not yet followed all the links) on why forecasts may fail: Snowquester: when forecast information fails.
The NWS Tauton office, which covers Boston, was very careful to emphasize the potential for a bust in all their discussions.
This was unsurprising. I basically listen only to NWS. They are generally sober, and as close as you can get to being right in weather forecasting. Most of the rest of the outlets just use NWS data, add advertising to it, and resell it. They are generally trying either to sell headlines or to prove some point about climate change.
Forecasting in the northeast is beginning to remind me of my years in Florida where during hurricane season, the slightest tropical depression beginning off the coast of Africa was going to become the next "Andrew."
I wish I didn't believe it, but I agree with TCD; advertising money for mass media is the driving force. Worst-case-scenario forecasting sells ad space.
It's just one other reason I told my cable company 2 years ago to hit the road and not to come back. I don't miss television and IMO can get better weather info online from NWS, NOAA, and MWOBS or by looking outside for that matter.
More snow!!!
Scott
"A society is defined not only by what it creates but also by what it refuses to destroy." - John C. Sawhill
Weather sells ads, and gets more eyes on those ads, I dont see that changing anytime soon.
Every time you see a TV weather forecaster use the phrase "I think that ...", it's a lock that what follows immediately thereafter is lifted almost verbatim from the NWS forecast discussion for that location. Very, very few of these media outlets have the resources to make independent forecast analyses.
sardog1
"Å! kjære Bymann gakk ei stjur og stiv,
men kom her up og kjenn eit annat Liv!
kom hit, kom hit, og ver ei daud og lat!
kom kjenn, hot d'er, som heiter Svevn og Mat,
og Drykk og Tørste og det heile, som
er Liv og Helse i ein Hovedsum."
-- Aasmund O. Vinje, "Til Fjells!"
The first paragraph of the article is very telling. It states that they fully realize an accurate forecast would be 0-14" of snow, but have no intention of reporting that information.
Is it better to forecast a horrendous Snowquester than admit the limited usefulness of computer models?
I heard a meterologist on one of the Boston stations observe that this type of storm was unusual in its size, intensity and location for this time of year. Consequently, there were few computer models to analyze.
Let's not fall into the trap of dismissing computer models. There has to be a history & pattern of storms to create models, and with climate change, we don't have enough data points to create reliable predictions. My gut says unpredictability will increase as the year-to-year climate temps go higher. Higher temps mean the atmosphere can carry more moisture.
The mind becomes purified by cultivating friendships with contented people, by being kind and compassionate to the sad and fearful, by being indifferent to the ill-intentioned, and by being accommodating to the well-meaning.--Sutra I:33
_________________________________________________
Some people walk in the rain. Others just get wet.--Roger Miller
IMO I think a lot of folks expect too much of the "Weather Man". As stated in this article and many other places..."Meteorology is not an exact Science"! I am not sure if it is apathy, ignorance, or just plain disinterest but I believe the individual has some personal resposibility in estrapulating the information they view about the weather. Local knowledge in any given area interjected with the wide array of info available is critical to understanding any given weather situation. One must keep their ear to the ground also and retain a feel for the trend rather than trying to short sight the forecast. One of the links in the original article somewhat touches on this general idea.
http://www.washingtonpost.com/blogs/...lG9M_blog.html
Last edited by skiguy; 03-08-2013 at 11:09 AM.
Don't need no stinking patches or decoder rings.
Agreed. Another excellent article by the Weather Gang: Your responsibilities as a weather forecast user.Originally Posted by skiguy
As forecasters, we strive to communicate weather information effectively. Sometimes we succeed, sometimes we fail. Either way, we’re committed to making our forecasts as useful as they can be and improving them. But for the delivery of forecasts to be successful, you, the end-user, have a set of responsibilities in receiving them.
Last edited by Mohamed Ellozy; 03-08-2013 at 12:00 PM.
Looks like we are on the same page on this one Mohamed. Interestingly the article talks about the particular difficulties of forecasting in the DC area compared to other areas. I believe it was within the last 5 to 10 years there was snow predicted by local forecasters in the Charlotte,NC area. They were correct about snow but not the "Exact Timing". They were predicting the snow to arrive late afternoon. Therefore employers sent everyone home at lunchtime with the strategy of getting everyone home and off the roads before the storm arrived. Unfortunately the storm arrived earlier than predicted and the local early commute was in progress. There were a lot of problems on the road. Afterwards the local community wanted the weatherman's head on a spear hanging from city hall. I believe a few of the weatherman in the area lost their jobs.
Don't need no stinking patches or decoder rings.
Excellent article. Uncertainty is a concept most people have a very difficult time with. And it does go both ways. Look at the storm that's winding down now: On Wednesday, my town (Sharon, MA) was predicted to get little, if any, accumulation. Thursday morning, the forecast rapidly changed to "as much as 8-12" total accumulation." Fast forward another 24 hrs: with two feet on the ground now and it still snowing, it's safe to say they underestimated this one. That's how it goes. Weather is a complicated phenomenon, and computer models are only as accurate as the data that HUMANS put in and the weighting functions that HUMANS apply. This is true of all computer models, not just those that deal with meteorology.
Preparedness isn't about what's in your pack. Experience isn't about how many mountains you've climbed.
Strange storm that hit Massachusetts! I left Brookline yesterday late morning thinking that the storm was over. Early this afternoon I looked at Boston.com and ... surprise!! ... it was back.
The forecasters had been saying for quite a while that it would be a long storm lasting into Friday. The big uncertainty was how much of it would be rain and how much would be snow because the low level temps were predicted to be very close to freezing.
It is sometimes easier to predict the water equivalent total of the precip than the form of said precip.
Just saw an explanation of what happened--a low (surrounded by a counter-clockwise wind flow) was predicted to pass SE of Boston (which it did). However, a high level low snuck in from the west, passing to the NW of Boston. The airflow combined to make a much larger counter-clockwise pattern which drew in an unexpectedly large amount of moisture from the ocean which fell in most places as snow.
I had off and on light snow yesterday with minimal accumulation and woke to heavy snow which lasted until 2pm today. (It was still snowing in some locations in MA at 6pm.) I measured 10-11 inches in my yard--Holden, MA reported 24.4 inches...
EDIT: Blue Hill Observatory reported 29.9 inches.
Doug
Last edited by DougPaul; 03-08-2013 at 10:24 PM.
Good point Kevin. Unpredictability of weather related events has already increased. Things like 100 year floods, intensity and patterns of hurricane paths, severity of droughts and severity of flooding, among many other indicators have been changing quickly over the past 2 decades with changes in climate patterns. The fact that we have seen most of the hottest 10-15 years in recorded history in this period does make it very difficult to predict since as you mentioned, models are based on the past years which have shown much more variation recently.
I agree the job of the meteorologist is very challenging and maybe more so now than ever. The issue i have is with the extreme sensationalism that decision-makers place around weather at mass media outlets and then use use to grab attention. I prefer my news, especially scientifically based news, to be presented in a responsible manner. It's my feeling some outlets have become irresponsible in this way. Unfortunately, everyone then blames the meteorologist for overdramatizing done by the suits selling ad space.
Scott
"A society is defined not only by what it creates but also by what it refuses to destroy." - John C. Sawhill
The global weather models used in weather forecasting can presumably make predictions based upon any quasi-realistic inputs (of the current weather conditions). However, models are developed using past data and may be less accurate when run on conditions that were not seen very often (or not seen at all) in the past data.
Computer models are the cornerstone of modern weather forecasting. They encapsulate much of our current knowledge of how weather works. However, many of the details still not known or poorly understood. The atmosphere is broken into gridboxes by location (5km and larger) and altitude and the enormous number of gridboxes required to approximate the earth requires an enormous amount of computation. In fact, the number of useable gridboxes is limited by the size of our largest supercomputers (more is better...). But still, there are many phenomena that are significantly smaller than the smallest gridbox and therefore cannot be modeled accurately. Thus while modern weather forecasting could not exist without computer models, the models are still just approximations. There are also multiple models--some are better at handling one situation and others are better at other situations. The forecasters generally look at the predictions from more than one model before making a prediction. (At least one of the Boston TV forecasters often shows the outputs of several models before stating his guess of which he believes is most accurate in the current situation.)Let's not fall into the trap of dismissing computer models. There has to be a history & pattern of storms to create models, and with climate change, we don't have enough data points to create reliable predictions. My gut says unpredictability will increase as the year-to-year climate temps go higher. Higher temps mean the atmosphere can carry more moisture.
Weather itself is driven by the heat energy flow from the sun-warmed tropics to the polar regions where it radiates back out into space. (The heat is carried by air movements, water movement, moisture in the air, changes between ice, liquid water, and water vapor, and radiation.) Weather, as we experience it, is just turbulence in the atmosphere driven by the heat flow. Turbulence, by its very nature, has limited predictability and will always limit our ability to predict the weather. The current limit of prediction (average accuracy vs time) is about two weeks. (In certain situations, such as this just past storm, the predictions for only 24 hours out can contain large errors...).
As for whether the weather is becoming more or less predictable, I have no idea. The climate is changing rapidly while our prediction techniques are improving. (The climate change appears to be increasing the severity of certain storms but that is not the same as reducing the prediction accuracy.)
Doug
Last edited by DougPaul; 03-09-2013 at 10:52 AM.
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