Weather conditions for Inauguration Day

[cycloneye]

First,off the bat,this thread is only to discuss all the aspects of how the weather will be on January 20th,when the swearing-in ceremony of the 44th President of the United States will take place and not discuss anything else apart from the weather.The thread will also have historical information about past Inauguration days in terms of weather.

A first glimpse from GFS shows good weather and not very cold temps.I know its very far and that is why we have to wait for more runs as the date gets closer.

12z GFS for January 20th

[cycloneye]

Weather of Inaugurations days in history and the normal weather at that date:

Normal high temperature for the day is in the low to mid 40's.

Normal low temperature for the day is in the mid to upper 20's.

Normal weather for the noon hour is about 37°F under a partly cloudy sky with a 10 mph wind.

There is about a 1 in 6 chance of precipitation during the ceremony.

There is only about a 1 in 20 chance of snow during the ceremony.

If it does rain or snow, there is a 4 to 1 chance it will only wet the pavement.

There is about a 3 out of 10 chance that there will be snow already on the ground from a previous snowfall.

More historic weather data at link.

http://www.erh.noaa.gov/lwx/Historic_Ev ... ation.html

[cycloneye]

Not a bad weather day according to the 360 hours data from GFS.Of course more changes will come as time gets shorter.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_360l.gif

[cycloneye]

12z GFS at 336 hours:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_336l.gif

[cycloneye]

The long range continues to show fairly good weather for January 20th.

12z GFS at 312 hours

[gotoman38]

Thanks for posting up the thread cycloneye!

I'll be on the National Mall to celebrate with many others on 1.20.2009 (weather permitting, naturally).

Currently, the accu people that cannot be mentioned are conditionally forecasting a mid 40's F day with partly cloudy conditions - that would be great!

Anyone else following the conditions closely??

[cycloneye]

Here is what the Capital Weather Gang says in their predictions for January 20th weather.

http://voices.washingtonpost.com/capita ... two_w.html

The 00z GFS at 288 hours continues the trend of good weather for January 20th.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_288l.gif

[cycloneye]

Thanks for posting up the thread cycloneye!

I'll be on the National Mall to celebrate with many others on 1.20.2009 (weather permitting, naturally).

Currently, the accu people that cannot be mentioned are conditionally forecasting a mid 40's F day with partly cloudy conditions - that would be great!

Anyone else following the conditions closely??

Thank you.I made this thread only to see how the weather will be on this historic day regardless of any political afiliation that the people have.

[cycloneye]

This is the January 20th,1961 inauguration when a blizzard swept thru D.C.

[Extremeweatherguy]

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[cycloneye]

A little more moist run at the 12z run of GFS and Brrrrrr cold for the 20th.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_288l.gif

[cycloneye]

Sunny but brrrrrrrrr cold!! in this 00z GFS run at 264 hours.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_264l.gif

[gotoman38]

Am I reading this as -20C = -4F, -10C = 14F on the morning of the 20th? That is bone chilling brrrrr for the mid-atlantic states!!

[cycloneye]

No change about the cold 20th! at the 12z run of GFS at 264 and 252 hours.
From tommorow we will have the Euro runs to see if coincides with GFS.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_264l.gif

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_252l.gif

[cycloneye]

Am I reading this as -20C = -4F, -10C = 14F on the morning of the 20th? That is bone chilling brrrrr for the mid-atlantic states!!

If you are going to the mall,go with three or four layers as it looks like it will be a cold day,however no snowstorm.

[cycloneye]

Capital Weather Gang in D.C. Latest Forecast for January 20th

Dan Stillmans update:

It's looking more and more likely that we'll see some serious cold in the nation's capital mid-to-late next week. Does it last into early the following week all the way to Inauguration Day? Or do temperatures moderate by the 20th? No way to say right now, but if I change my forecast soon, odds are it will be in the colder direction, not warmer.

Previously... The extended range indicators are leaning toward temperatures slightly below normal around the time of Inauguration Day. I'm not ready to go full force in that direction, but am bumping my forecast down a couple degrees.

Also, I don't see anything in the data to justify changing my initial stab of a 30% chance of rain, with frozen precipitation staying north and west of D.C.

As I expected, the atmospheric index known as the NAO is forecast to be in the positive range, which as Jason recently explained tends to limit snow. So, I'll stick with my call against a big winter storm.



Jason Samenows Update:

Today's Update:: The cold pattern, which more than likely blasts into the area in the middle to latter part of next week, increasingly looks like it may have some staying power. So while I'm currently forecasting slightly colder than average weather, I may have to adjust temperatures down in the coming days. Still too soon for me to say any more about the chances of storminess...

Previously... I'm sticking with my previous forecast for the time being.

The real question is whether the ridge in the jet stream in the West forecast by long-range models to develop will hold. If it holds, we'll have a dip in the jet stream over the East that will likely bring us colder than average weather. If it breaks down, we'll have more moderate conditions with Pacific rather than Canadian air. I'm betting on the colder scenario -- but it's a close call.

Storminess remains nearly impossible to predict this far out, but my gut feeling suggests there will be some within a day or so of inauguration that will add a wrinkle to the forecast.


http://voices.washingtonpost.com/capita ... _blas.html

[cycloneye]

Here is the first run from Euro for January 20th and it looks Cold but without Precipitation.Lets see if this changes in further runs of the model.

http://www.ecmwf.int/products/forecasts ... 9011000!!/

The 00z run of GFS shows a little more liquid run than past runs and is distint from the Euro.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_228l.gif

[cycloneye]

The 12z GFS run at 228 hours shows some moistere and cold temps,but anything that looks like a Blizzard for the 20th in D.C.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_228l.gif

[cycloneye]

The 12z Euro for the 20th shows a clipper west of D.C. with cold temps.

http://www.ecmwf.int/products/forecasts ... 7091412!!/

[jimvb]

2008 Jan 11 06Z GFS run seems to show snow for the Inauguration in DC. The 0 line goes through Woodbridge or so, and there is a moderate precipitation blob in and near the capital. Accuweather calls for "periods of snow" for the Inauguration. If that happens, there could be some real problems. This is already a nightmare with all the security, the crowds expected, closing of bridges threatening traffic jams in RICHMOND, a problematic train trip, and all of the hype being piled on this inauguration. Add a 4-inch snow to that and you have some real problems. There have been some inaugurations in the snow before, however.

2008 January 11 09:23 EDT. This post requires an update. Accuweather now only calls for "partly cloudy" or something like that for Inauguration Day. It changed while I was writing my post. However, GFS still calls for some wintry precipitation for the Inauguration, and Accuweather still calls for "periods of wet snow" for Richmond on the night of the 20th.