DCA March Toward a -20 Week

[WEATHER53]

Sunday:-22.5

Monday:-24

Tuesday:-15.5

Wednesday:-16

Thursday:-24

Friday:-26.5

Saturday:-16

[WEATHER53]

We will be able to achieve a -20 week.

[WEATHER53]

Sunday:-22.5

Monday:-24

Tuesday:-15.5

Wednesday:-16

Thursday:-24

Friday:-26.5

Saturday:-16

We Did It:-20.6 average for the week .

[Ian]

Noted in recent extremes thread but was coldest week since Jan 1994. That cold snap might be hard to beat..

H	L	Avg
22	11	16.5
20	10	15
31	17	24
34	13	23.5
21	11	16
22	5	13.5
35	14	24.5
		
	7-day avg	19

[RodneyS]

 

Noted in recent extremes thread but was coldest week since Jan 1994. That cold snap might be hard to beat..

H     L	        Avg
22	11	16.5
20	10	15
31	17	24
34	13	23.5
21	11	16
22	5	13.5
35	14	24.5
		
	7-day avg	19

Remarkable week, but compare with what I would argue was the most extraordinary week in DC weather history, February 9-15, 1899:

 

H       L    Avg

10    -7    1.5   9th

 4    -8     -2    10th (coldest average in DC history)

12   -15   -1.5  11th (coldest minimum in DC history; 0.5 inch of snow)

11      4     7.5  12th (7.0 inches of snow)

10      5     7.5  13th (12.0 inches of snow) 

24      5   14.5  14th (1.0 inch of snow)

35    -6    14.5  15th

        

    7-day avg    6.0 (coldest in DC history)

[WEATHER53]

 

 

Noted in recent extremes thread but was coldest week since Jan 1994. That cold snap might be hard to beat..

H     L	        Avg
22	11	16.5
20	10	15
31	17	24
34	13	23.5
21	11	16
22	5	13.5
35	14	24.5
		
	7-day avg	19

Remarkable week, but compare with what I would argue was the most extraordinary week in DC weather history, February 9-15, 1899:

 

H       L    Avg

10    -7    1.5   9th

 4    -8     -2    10th (coldest average in DC history)

12   -15   -1.5  11th (coldest minimum in DC history; 0.5 inch of snow)

11      4     7.5  12th (7.0 inches of snow)

10      5     7.5  13th (12.0 inches of snow) 

24      5   14.5  14th (1.0 inch of snow)

35    -6    14.5  15th

        

    7-day avg    6.0 (coldest in DC history)

 

Rodney. Thanks you for that. It would be my set of facts that in order to compare 1899 DC stats to DCA 2015 you would need to add 10 degrees to all the values to make comparative. 

[WEATHER53]

Sunday:-22.5

Monday:-24

Tuesday:-15.5

Wednesday:-16

Thursday:-24

Friday:-26.5

Saturday:-16

DCA followed this up with a second week averaging -10

[WEATHER53]

DCA followed this up with a second week averaging -10

DCA will follow up the 2nd week with a -9 3rd week.  Likely the lengthiest cold since 1977.

Even with all of it's irregularities DCA was able to do this. The irregularities will be on full display tonight, already are with DCA running +10 to surrounds. See, I believe in thermodynamics.  There is NO heat mechanism down there to be able to overwhelm snowcover, frozen river, etc. Any suggestions that building to the west are somehow radiating out so much warmth are frankly absurd. What might make more sense is, oh I don't know, something along the lines that having sensors properly located involves having to leave the office and deal with security so just put up a thermometer next to the office on top of the roof and just measure the snow there also because nobody other than a bunch of weather weenies really care if Snowmaggedon accumulated 16" or 25-30". It's an FAA facility, not a NWS one and certainly not a Weenie one.

[MN Transplant]

DCA will follow up the 2nd week with a -9 3rd week.  Likely the lengthiest cold since 1977.

Even with all of it's irregularities DCA was able to do this. The irregularities will be on full display tonight, already are with DCA running +10 to surrounds. See, I believe in thermodynamics.  There is NO heat mechanism down there to be able to overwhelm snowcover, frozen river, etc. Any suggestions that building to the west are somehow radiating out so much warmth are frankly absurd. What might make more sense is, oh I don't know, something along the lines that having sensors properly located involves having to leave the office and deal with security so just put up a thermometer next to the office on top of the roof and just measure the snow there also because nobody other than a bunch of weather weenies really care if Snowmaggedon accumulated 16" or 25-30". It's an FAA facility, not a NWS one and certainly not a Weenie one.

 

The ASOS is east of the runway on the south side of the peninsula.  Nowhere near a building.

 

http://weather.gladstonefamily.net/site/KDCA

[winterymix]

The ASOS is east of the runway on the south side of the peninsula.  Nowhere near a building.

 

http://weather.gladstonefamily.net/site/KDCA

The do report the statistical temperature error:

 

 

Temperature     24 hours   Day time   Night time Average temperature error -2.1 °F -2.3 °F -1.9 °F Error standard deviation 1.4 °F 1.3 °F 1.4 °F

NOTE: If the error above is POSITIVE, then it means that the analysis temperature is HIGHER than the reported temperature. This means that your sensor is reading COLDER than expected.

[WEATHER53]

The ASOS is east of the runway on the south side of the peninsula.  Nowhere near a building.

 

http://weather.gladstonefamily.net/site/KDCA

It has been suggested so but unlike many of you I have been on site.  It is my belief that the often pictured tarmack type location could not possibly produce such values and measurements. I have been told, implicity, that they do not go out there for snow measurements. Too far, DCA has a lot of security protocol, etc. I was also told that my question of are snowfall measures taken in a more convenient to access location, like right out the door of the office, or was it based on melted liquid equivalent was a question that would not be answered. This response was quickly followed by a repeat of the operating concept that this is an FAA facility and not a NWS one. The session then ended. If anyone wishes to challenge me then so say and if you request I can e-mail you the office number and you can call to try to initiate your own research and questions.  If anyone know some things about it then so state and challenge me to provide the initials, in reverse order, of two parties who work there. I can publish that here.

I have spent years with my assertions but sort of tap dancing around it because I know the people. It's gotten to the point that staying the course is a part of a form of fundamental arrogance that has lead to this issue. Sometimes you have to go to north Florida to find the values that DCA posts, even Raleigh is often lower. When it was 3/4/5 degrees like in the 70's that was one thing ;we are now to the point that 10-15 is quite common and in a few more years it will be common for 15-20. It needs to stop, put the light on it and get it right.  

[Ian]

It has been suggested so but unlike many of you I have been on site.  It is my belief that the often pictured tarmack type location could not possibly produce such values and measurements. I have been told, implicity, that they do not go out there for snow measurements. Too far, DCA has a lot of security protocol, etc. I was also told that my question of are snowfall measures taken in a more convenient to access location, like right out the door of the office, or was it based on melted liquid equivalent was a question that would not be answered. This response was quickly followed by a repeat of the operating concept that this is an FAA facility and not a NWS one. The session then ended. If anyone wishes to challenge me then so say and if you request I can e-mail you the office number and you can call to try to initiate your own research and questions.  If anyone know some things about it then so state and challenge me to provide the initials, in reverse order, of two parties who work there. I can publish that here.

I have spent years with my assertions but sort of tap dancing around it because I know the people. It's gotten to the point that staying the course is a part of a form of fundamental arrogance that has lead to this issue. Sometimes you have to go to north Florida to find the values that DCA posts, even Raleigh is often lower. When it was 3/4/5 degrees like in the 70's that was one thing ;we are now to the point that 10-15 is quite common and in a few more years it will be common for 15-20. It needs to stop, put the light on it and get it right.  

Dude.. for someone pretty smart you should step back and re-assess this one.

 

The ASOS doesn't take snow measurements for one.. that's where all the automated items like temp/rain/wind are gathered. I know exactly where they measure snow. It's right outside the terminal next to a public sidewalk.. anyone could walk right past it and probably see it on a snow day.

 

Presently it is 24 at DCA. Here are city readings from weatherbug:

 

WTOP: 22

Nationals Park: 23

Childrens Hospital: 23

Maury ES: 22

 

Here's wunderground showing others about that temp in and around the city:

 

 

Must be some vast conspiracy if these other stations are in on it.

[gymengineer]

Dude.. for someone pretty smart you should step back and re-assess this one.

 

The ASOS doesn't take snow measurements for one.. that's where all the automated items like temp/rain/wind are gathered. I know exactly where they measure snow. It's right outside the terminal next to a public sidewalk.. anyone could walk right past it and probably see it on a snow day.

 

Presently it is 24 at DCA. Here are city readings from weatherbug:

 

WTOP: 22

Nationals Park: 23

Childrens Hospital: 23

Maury ES: 22

 

Here's wunderground showing others about that temp in and around the city:

 

 

Must be some vast conspiracy if these other stations are in on it.

I *love* this map because it clearly shows the elevation rise that immediately surrounds DC's downtown business core. The temps on it also clearly show the possible temp contrast on any given night between near-DCA part of Arlington and near-Fairfax County part of Arlington. 

[Ian]

I *love* this map because it clearly shows the elevation rise that immediately surrounds DC's downtown business core. The temps on it also clearly show the possible temp contrast on any given night between near-DCA part of Arlington and near-Fairfax County part of Arlington. 

Yes, though actually a good chunk of DC is fairly low elevation. It's really the area NW of Rock Creek Park that has the real elevation. It does gradually increase going north to the east but I think in a lot of cases those areas end up similar if a little colder/snowier than downtown because it's still considerably urban in a lot of that area.  Obviously downtown area is the worst.. and you can see similar to a degree in other urban spots across the area. No doubt they are anomalous in that they would be colder if there wasn't anything there. Upper NW has elevation and much less density of buildings.

 

As far as snow, I think we have enough evidence from people here that there is a real and fairly tight gradient between DCA/Mall/Downtown and places north.. it's slow until you hit the hillier zones then there's a bit of a jump then it's sorta slow again going north/west/northwest from there. 

 

I've seen and walked through a lot of snow events here now at various elevations and portions of the city. For Mar 25 last year I went to Fort Reno and they had a good bit more snow than me and downtown was pretty meh comparatively. Even just going up the hill from Ct Ave in my neighborhood to the Cathedral there is often a noticeable difference in marginal events.  Most of the people who complain the loudest and with the most conviction don't completely seem to understand all that is involved. 

[Deck Pic]

DCA will follow up the 2nd week with a -9 3rd week.  Likely the lengthiest cold since 1977.

Even with all of it's irregularities DCA was able to do this. The irregularities will be on full display tonight, already are with DCA running +10 to surrounds. See, I believe in thermodynamics.  There is NO heat mechanism down there to be able to overwhelm snowcover, frozen river, etc. Any suggestions that building to the west are somehow radiating out so much warmth are frankly absurd. What might make more sense is, oh I don't know, something along the lines that having sensors properly located involves having to leave the office and deal with security so just put up a thermometer next to the office on top of the roof and just measure the snow there also because nobody other than a bunch of weather weenies really care if Snowmaggedon accumulated 16" or 25-30". It's an FAA facility, not a NWS one and certainly not a Weenie one.

 

Snow is fine there.  I think there used to be some issues, but over the last 4 years they have gotten much better.  I know this because I have personally measured 81 consecutive accumulating snow events, and my snow climo is pretty close to DCA, though I am at a higher elevation and further north.  This year so far I have 20.0" and DCA 18.3", last winter I had 36.5" and DCA 32.0".  I am intimately familiar with almost every event since 2004-05.  I'm not an expert at many things, but at DC snow, I am an expert.  I think your temperature suggestions are more a factor of the location of the airport which we all agree is in a really bad spot.  DCA is not alone.  A lot of airport locations have really bad UHI.

[Deck Pic]

Here is a current pic taken from my window. I have no idea why I'd be warmer at night than surrounding areas. Lol

[Ian]

Here is a current pic taken from my window. I have no idea why I'd be warmer at night than surrounding areas. Lol

 

end of the day here today (not that it's all that much colder here):

 

[Deck Pic]

end of the day here today (not that it's all that much colder here):

 

 

we actually have really good snowcover here.  The sun didn't do much damage.  But asphalt is asphalt, and they clear it, and it does a stellar job of retaining heat.  I'm pretty sure at DCA, the parking lots, tarmack, roads are all clear and trapped heat all day.

[Ian]

we actually have really good snowcover here.  The sun didn't do much damage.  But asphalt is asphalt, and they clear it, and it does a stellar job of retaining heat.  I'm pretty sure at DCA, the parking lots, tarmack, roads are all clear and trapped heat all day.

yeah dupont was still totally covered when i left where there was grass.. prob still lost/compressed/etc like 1-2 or so there tho I'd guess. and yes definitely.. that whole area is full of parking lots soaking up march sun angle.

[Deck Pic]

1am OBS

 

DCA: 22

IAD: 6

 

NYC 20

LGA 22

JFK 21

SMQ (Somerset Airport) 5

[arlwx]

5am:

 

DCA 20

IAD 3

BWI 9

[winterymix]

Low this AM in my area = -2

[WEATHER53]

Here is a current pic taken from my window. I have no idea why I'd be warmer at night than surrounding areas. Lol

Your window and the almost parklike setting of DCA are entirely different. A person of your merit should be able to present something stronger than this. If the official station for the Nations Capitol had a thermometer on a bird feeder hook 6' off the ground right in front to the entrance to The Williard then that would be like "out your window" but not on a strip of land surrounded by frozen water to the east and south, a snow covered tarmack absent runways, a moderately used parkway to it's west. In fact, any real office buildings like "out your window" are hundreds of yards away.  What heat generating device is there down there that can overcome snow cover, frozen waters, and a borderline parklike location; there answer is-Nothing. For a while the River was thrown out but Annapolis does not have the same issue. You all have got to stop believing that some fanciful device of warmth can overwhelm snowcover, bitter cold temps, etc

[WEATHER53]

5am:

 

DCA 20

IAD 3

BWI 9

Was Jacksonville Fl colder at 5am?

[Ian]

Was Jacksonville Fl colder at 5am?

If you count 41 as colder, yes.

[Ian]

Lows on wxbug:

WTOP 18

Nats Park 19

Childrens 20

Maury ES 19

Sounds like DCA is right once again.

[NoVaSnow]

I've said this before, and I'll say it again.

 

For the past 7+ years, I have worked in Crystal City, right next to DCA. I have determined that my car thermometer consistently reads 2 degrees high. Whenever I arrive at work, I note the temp on my car thermometer. I then check the reported temperature at DCA. At least 90% of the time, the official reading is within 1 or 2 degrees of what I calibrate from my car.

 

It's just a location thing. It does not get as cold at DCA as it does at most other places in the region. Deal with it.

[Deck Pic]

Your window and the almost parklike setting of DCA are entirely different. A person of your merit should be able to present something stronger than this. If the official station for the Nations Capitol had a thermometer on a bird feeder hook 6' off the ground right in front to the entrance to The Williard then that would be like "out your window" but not on a strip of land surrounded by frozen water to the east and south, a snow covered tarmack absent runways, a moderately used parkway to it's west. In fact, any real office buildings like "out your window" are hundreds of yards away.  What heat generating device is there down there that can overcome snow cover, frozen waters, and a borderline parklike location; there answer is-Nothing. For a while the River was thrown out but Annapolis does not have the same issue. You all have got to stop believing that some fanciful device of warmth can overwhelm snowcover, bitter cold temps, etc

 

You don't understand how UHI works.  It isn't restricted to a tiny area.  Science doesn't work by thinking your way through it.  I've driven a car a ton of times in the summer and winter, and I have seen UHI at work, and this is non-traffic induced.   DCA is in a really bad location.  The low last night there wasn't actually 10 or 12 or even 15....That is preposterous...Now if their sensor is on the roof and that is where the temp is taken, then that is inappropriate, but it isn't going to make the temp as cold as Andrews.  You have never gotten specific.  The low last night at DCA was 19. What do you suggest the low actually was?  And are you specifically saying the sensor is purposely calibrated to read high?   Best to be specific.  

 

LOWS

 

BOS: 17

NYC (In central Park!) - 18, and their snow depth is 19"!!!!

LGA - 20

Somerset Airport - North Jersey: -1

[NoVaSnow]

You don't understand how UHI works.  It isn't restricted to a tiny area.  Science doesn't work by thinking your way through it.  I've driven a car a ton of times in the summer and winter, and I have seen UHI at work, and this is non-traffic induced.   DCA is in a really bad location.  The low last night there wasn't actually 10 or 12 or even 15....That is preposterous...Now if their sensor is on the roof and that is where the temp is taken, then that is inappropriate, but it isn't going to make the temp as cold as Andrews.  You have never gotten specific.  The low last night at DCA was 19. What do you suggest the low actually was?  And are you specifically saying the sensor is purposely calibrated to read high?   Best to be specific.  

 

LOWS

 

BOS: 17

NYC (In central Park!) - 18, and their snow depth is 19"!!!!

LGA - 20

Somerset Airport - North Jersey: -1

 Thanks, Matt.

[Deck Pic]

Lows on wxbug:

WTOP 18

Nats Park 19

Childrens 20

Maury ES 19

Sounds like DCA is right once again.

 

my low was 20 and the closest station to me has a notorious cold bias.  

 

I don't know why we engage. H**ward is not interested in debate.  He is interested in chest thumping and telling us how it is. Every time I have presented factual evidence that counters his assertions, he completely ignores it.  I would like him to explain to me how NYC was 18 last night in the middle of park land with 19"  snow depth.