"56 degrees Fahrenheit, a 6 mph tailwind - but 93% humidity"

I must enter a name. wrote:

Thanks Muggy. That is the data I've been searching for, for the last 24 hours. How were you able to get it? I had the same problem with redirecting to Logan.

Looks like you can get there by clicking directly on the station name, e.g. if you're on the page for Brookline, Massachussetts, click the "White Place Station" to go to the station page and then scroll down to the history. If you just click the "history" tab it defaults to the Airport station.

malmo wrote:

Harambe wrote:

This is a dewpoint of 54F. That's very ideal. It's just not an issue AT ALL. Find another excuse.

Agreed. Here's the actual data. It doesn't get much better. Mostly cloudy and a strong tailwind makes it a fantastic day.

Time / Temp / DP / RH / W Dir / W speed / W gusts / Condition

8:54 AM 63 F 55 F 75 % S 12 mph 0 mph Mostly Cloudy

9:54 AM 67 F 55 F 66 % S 14 mph 0 mph Mostly Cloudy

10:54 AM 69 F 52 F 54 % SW 15 mph 0 mph Mostly Cloudy

11:44 AM 59 F 50 F 72 % W 22 mph 39 mph T-Storm / Windy

11:54 AM 59 F 50 F 72 % W 22 mph 33 mph Light Rain / Windy

12:54 PM 59 F 49 F 69 % W 25 mph 31 mph Mostly Cloudy / Windy

I know where you pulled the data from but it is completely false to what the conditions were on course... From the top of the Heartbreak Hill to the finish, there was no running in shade.... During this stretch in the time frame from noon to about 1pm, when I ran there the temps were up to 69F, humidity 80-90%, sunny, barely windy, 10mph tops, from SSW, maybe SW... I call bullshit on all the above data.

I ain't complaining, just stating. I know this is Boston, you take what it gives you and run with it;)

This was more realistic weather tracker:

http://findmymarathon.com/weather/boston-marathon-weather.php

Now that I understand how to get previous data on wunderground (thanks) I looked at a few more stations especially in the middle of the race. This is when things started to go wrong for a lot of people, and personally it started to feel differently. I'm not sure exactly where the weather station is at (just the town) but it shows that I ran through a dew point around 59 as early as mile 5, and that high again in Newton. In fact it looks like just about all of the race was somewhere between 56-60.

That is definitely going to take a toll on somebody who is not acclimated, especially when you add in the noon day sun.

If a 3 hr runner came in, with perfect knowledge of what the weather was going to be, and readjusted their goals immediately, it might have only cost them a few minutes, but many runners probably didn't realize it wasn't just the normal fatigue that comes during an endurance event, and especially if their weekly mileage wasn't super high, probably wilted with 20min.+ positive splits.

Hardloper wrote:

I must enter a name. wrote:

Thanks Muggy. That is the data I've been searching for, for the last 24 hours. How were you able to get it? I had the same problem with redirecting to Logan.

Looks like you can get there by clicking directly on the station name, e.g. if you're on the page for Brookline, Massachussetts, click the "White Place Station" to go to the station page and then scroll down to the history. If you just click the "history" tab it defaults to the Airport station.

Also if you open up the WunderMap you can see all of the stations with current wind and temp, and click on them to go to that station's page. Used this a lot this winter when trying to find the least windy place for a track or tempo workout on a given day.

I must enter a name. wrote:

If a 3 hr runner came in, with perfect knowledge of what the weather was going to be, and readjusted their goals immediately, it might have only cost them a few minutes, but many runners probably didn't realize it wasn't just the normal fatigue that comes during an endurance event, and especially if their weekly mileage wasn't super high, probably wilted with 20min.+ positive splits.

My PR is 2:59 from the fall in low 40s weather (on 75 mpw). Monday I ran 3:11 (similar training). I think part of it was the hills, which I frankly did not prepare adequately for, but I was also really suffering from the heat starting around mile 16 or so when the cloud cover gave way to sunshine.

bj;oh wrote:

Ok. You might be right when it comes to running but it is in fact a general rule that people are not bothered by dew points lower than 60F. Cool air simply can not hold enough water. At 80F the air can hold 5 times as much water as when it is 50F! That why a relative humidity of 72% is absolutely miserable at 80F but a relative humidity of 40% at 80F is delightful. .

wrong reason. It's not the amount of water but the partial pressure of the vapor, which limits rate of evaporation from the skin. If you needed to sweat as much at 60F as at 80F, the higher humidity would be a lot worse. Fortunately, you don't have to sweat nearly as much, because the rate of heat loss by conduction is much higher. The best possible way to maximize that is low subcutaneous body fat.

The best possible way to deal with humidity is to acclimatize to humidity., i.e. get used to it over a few weeks. I do not understand why the tv news weather or online weather stations do not focus more on the dewpoint. Some times they mention it, if it's really high and sustained like over 70F. It's actually a very important element in the weather forecast. A temperature of 80F can mean misery or delight depending on the dew point. Below like 50-55F it does not matter, running or not.

Humidity is worthless to report, dewpoint is what matters

You can figure the dew point if you know the relative humidity and temperature. But not too many people can do this calculation in their head and even if they could most do not know the importance of the dew point as it relates to their comfort. It would be best if tv news weather reports said something like "It's clear out now, the temperature is 73F and the dew point 65F. A little sticky out there" . From that you know it feels a bit muggy AND you know it's going to be warm all night. The dew moves very slowly, unless there's a front that comes through. This means the low temperature will not drop below 65F as the dew point can not exceed the temperature. So if you run and the temperature is 55F or above always look for the dew point: Here's a very rough idea what to expect at various dew points:

55-60F: Very light humidity. Hair gets soaked if running at closer to 60F. but no major effect on performance.

60-65F: Moderate humidity. Now shirt get soaked. Running is noticeably harder.

65-70F: It's humid. Tough to run in. Major perspiration.

70-75F: Makes you feel miserable. You may want to stay in. If you run you will feel exhausted.

75F+: Unless you live in the Persian Gulf and similar places you will thankfully never experience this torture.

It clearly wasn't ideal weather conditions for a marathon. Sorta average for the time of year perhaps?

Exactly, seems to be an awful lot of time spent arguing if conditions were great or horrible. For most people the conitions were somewhere in the middle. Time to move on

People who ran want to use the weather as an excuse. People who didn't run or had a good day want to deflate that excuse.

I ran, had a bad day, so also will blame the weather.

Ha. I ran and had a good day but trying to find a reason why I didn’t have a better day. But I always do that.

The bottom line with the weather was that leading up to it there was some talk about whether or not a dew point in the mid50s would have any effect on runners. Some people said yes, some people said no. What actually happened was the dew point was close to 60, and it had an effect on almost everybody. If you went in assuming you'd be fine, you probably weren't. If you almost immediately changed your goal pace by maybe 10 seconds a mile, you probably wound up OK.

Fortunately there were no major medical problems, because I think generally these were the sort of conditions that wear you down and force you to go slower... not the type that you can fight through and cause yourself a medical emergency by not giving in. Runners also did not have a lot of mental time to adjust to the forecast... most people packing probably were more prepared for 40 degree weather with headwind than upper60s.

I should add, that I suspect that most people that had a good day, already had a moderately conservative goal pace. The conditions were such that if you never went over the edge, there is no reason you couldn't have run steady with probably a slight fade.

The weather was great. I dropped at 21 after running near 2:30 pace for reasons entirely unrelated to the weather, the only people who have an excuse to complain are the slower folks who got caught in a driving rainstorm after 2pm and probably went hypothermic because they weren't moving quickly. It was about as good as Boston gets.

First off, I didn't race on Monday. I did last year. People claiming that a dew point under 60 doesn't have an effect on runners are nuts. 55-60F dew points are still humid. It may not feel muggy going outside for a walk, but running for 2+ hours is a different story. I don't understand people here trying to rain on the parade (pun intended) of Monday's accomplishments. Running a marathon in the upper 50s-low 60s when many of us haven't had more than a day or two of training in those temps in months is a disadvantage. I think most runners would have preferred temps closer to 30 than 60.

Harambe wrote:

This is a dewpoint of 54F. That's very ideal. It's just not an issue AT ALL. Find another excuse.

Wait are people trying to claim it was a slow day? I wouldn't call it a historically fast day, but slightly faster than average.

If you want to argue that common runners got stuck in some morning rain waiting in Hopkinton, I'll slightly take that into account, but still should be faster than average.