HIExpress

Weather for the 117th Running of the Boston Marathon 4/15/2013

Posted by: HIEXPRESS, 4:13 AM GMT en Marzo 22, 2013

I'm back to the Boston Marathon this year. I have a bib for this year, but a recent injury has sidetracked my training. It has improved enough so it looks like I will be able to run it. I have a BQ for next year also, so I will look forward to racing it then. Now, a little over three weeks out, what does the weather look like for race day?

According to the Climate Prediction Center, patterns in the near term favor below normal temperatures and precipitation in the Northeast in the 8-14 day outlook.Link

while their long lead seasonal outlook favors "ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES CONTINUE FOR THE GREAT LAKES REGION, THE NORTHEAST, etc.." and "EQUAL CHANCES OF
BELOW, NEAR AND ABOVE MEDIAN SEASONAL PRECIPITATION AMOUNTS" for the Northeast.
"ENSO-NEUTRAL CONDITIONS ARE LIKELY TO CONTINUE THROUGH BOREAL SPRING 2013."

The two forecasts are at odds on the temperature, and the date of the marathon falls in between the two forecast periods. This fact is borne out in the 30 day discussion from the NWS 30-DAY OUTLOOK DISCUSSION FOR APRIL 2013
"CONFIDENCE IS SUPPRESSED BECAUSE WE NEED A LARGE CHANGE
IN THE CURRENT CIRCULATION PATTERN FOR THIS FORECAST TO VERIFY."
______________________________
From my 2008 BAA marathon weather blog:
According to WU almanac/archives, the averages for 4/21 are:
The Average High Temperature is 62 F with a historical range of 48 F to 87 F
The Average Low Temperature is 44 F with a historical range of 36 F to 55 F

There is a 57% chance of a Warm Day (temperature over 60°F / 16°C).
(16 days out of 28 in historical record)
The Average Daily Precipitation is 0.11 with a historical range of 0.00 to 0.67
There is a 36% chance of a Precipitation Day.

Average Cloud Cover is partly cloudy
There is a 18% chance of a Cloudy Day.

The Average Wind is 10 mph with a historical range of 5 mph to 17 mph
There is a 43% chance of a Windy Day (average wind over 10 mph / 15km/h).

Humidity:
The Average High Dew Point is 45 F with a historical range of 23 F to 59 F
The Average Low Dew Point is 30 F with a historical range of 10 F to 49 F
There is a 0% chance of a Humid Day (dew point over 65°F / 18°C).

The 26.2 mile race starts further inland in Hopkinton, MA, and they average 2F colder than Boston. Graphical Averages

Historically, race day conditions are either cooler than normal, with a headwind, or warmer than normal, with a tailwind. As the Boston Marathon is a straight point-to-point run, the wind shouldn't change much during the race, but a wide swing in conditions during the race is a possibility (especially for those who, like me, are going to take several hours to complete the run). A survey of race day weather from past Strong LaNina years indicates that slightly warmer than normal temperatures and a tailwind are favored.
________________________________
It appears that ENSO neutral conditions like we have now favor neither of the usual race day weather regimes.

The CPC Prognostic Discussions
Valid: Mar 27 - 31, 2013 (6-10 Day Outlook)
Valid: Mar 29 - Apr 04, 2013 (8-14 Day Outlook)
Issued: Mar 21, 2013
list these analog years to the current pattern:
ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
20010330 - 19710322 - 19720402 - 19520331 - 20050318

ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
20010329 - 20010323 - 19710321 - 19510310 - 19600311

According to WU archives,
April 2001 featured only one day with a low below freezing, and not a single day with a high temp below 45F. Additionally, 10 days had a high temp of above 60F, with 2 days having high temps above 75F.

April 1971 was similar. The highest temp days had the wind out of the West (a tailwind).

Living and training in Florida year round, my preference is: the warmer, the better. :)

I will look again as the date comes within the range of the 16 day GFS (obviously a low %age forecast; the resolution improves 7 days out) and other models.

Updated: 4:15 AM GMT en Marzo 22, 2013

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Weather for the 117th Running of the Boston Marathon 4/15/2013

Posted by: HIEXPRESS, 4:13 AM GMT en Marzo 22, 2013

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2010 ING New York City Marathon Weather

Posted by: HIEXPRESS, 12:39 AM GMT en Octubre 31, 2010

Starting one week from race day, just to get an idea what to expect. The forecast will change,so look to the comments below for updates...Hope it doesn't happen, and at 180 hours out the forecast is certain to numerous times, but the GFS keeps returning to cold & rain (or some form of precipitation) for this year's NYC marathon. http://wxweb.meteostar.com/sample/sample.shtml?text=KNYCThe official NWS forecast seems to agree more with the ECMWF model calling for bet...

Updated: 12:20 AM GMT en Noviembre 10, 2010

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Central Florida Sports Weather

Posted by: HIEXPRESS, 12:48 AM GMT en Noviembre 19, 2009

A place for Runners, Cyclists, Tri, Fishing, Ball Sports, Equestrian, & all others participating, watching, and/or supporting outdoor sports in Central Florida (anywhere else is OK too WU bloggers) to comment on how the weather will affect your event. Have an event planned? - Post it!Have an opinion on what the weather will be like for an event - tell us what and why!Just completed an event? - tell us how you did and how the weather worked out for you. Tell us abou...

Updated: 3:17 PM GMT en Marzo 04, 2010

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2008 Boston Marathon Weather

Posted by: HIEXPRESS, 2:29 AM GMT en Marzo 21, 2008

The 112th Boston Marathon is scheduled for Monday, April 21, 2008, and one month out now, it still looks like we will have good weather. You may remember that after receiving pre-race emails from the BAA warning about extreme conditions, last year's runners saw race day conditions improve at the last minute, warming from near freezing temps and a very strong headwind, although the rain and some headwind persisted. According to the CPC, the current ENSO outlook is fo...

Updated: 12:14 PM GMT en Abril 20, 2009

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