Counting Down to Washington's Record Warmest Year: "It Hasn't Warmed Since 2012!"

Record Hot Year Countdown Scorecard

Date  High Low 2012-YTD 1991-YTD Departure to Miss 
12-10 63   49   62.7      61.5    -18.1    
12-11 62   41   62.6      61.4    -19.5 
12-12 47   39   62.6      61.4    -20.7  
12-13 50   35   62.5      61.4    -22.1 
12-14 52   30   62.5      61.4    -23.4 
12-15 54   37   62.4      61.3    -25.2
12-16 52   46   62.4      61.2    -27.6
12-17 55   48   62.4      61.1    -30.5
12-18 62   43   62.3      61.1
12-19 54   36   62.3      61.0
12-20 53   41   62.2      60.9    -41.0  
12-21 59   39   62.2      60.8
12-22 45   35   62.1      60.8
12-23 47   29   62.1      60.7
12-24 41   31   62.0      60.7
12-25 51   34   61.9      60.6 
12-26 45   33   61.9      60.5
12-27 43   37   61.8      60.5
12-28 45   36   61.8      60.4
12-29 42   34   61.7      60.4
12-30 42   32   61.6      60.3
12-31 41   29   61.6      60.2 

(Departure to Miss indicates how much the average temperature must be below normal for the rest of the year in order to avoid setting a new record for warmest year.)

January 2 Update: Thanks to a quirk in calculation methodology, the National Weather Service is rounding down the final average to 61.5°. It was also the record warmest year at Washington Dulles and the 3rd warmest at Baltimore. From the NWS report:

2012 WAS THE WARMEST YEAR ON RECORD FOR WASHINGTON DC WITH AN ANNUAL AVERAGE TEMPERATURE OF 61.5 DEGREES. THE PREVIOUS WARMEST ANNUAL AVERAGE TEMPERATURE ON RECORD WAS 60.2 DEGREES IN 1991. THE AVERAGE TEMPERATURE FOR 2012 WAS 3.3 DEGREES ABOVE THE 1981-2010 NORMAL AND WOULD BE COMPARABLE TO THE NORMAL ANNUAL TEMPERATURE OF ATLANTA...OKLAHOMA CITY AND SAN JOSE...JUST TO NAME A FEW LOCATIONS.

DULLES ALSO EXPERIENCED THEIR WARMEST YEAR ON RECORD WITH AN ANNUAL AVERAGE TEMPERATURE OF 57.9 DEGREES IN 2012. THE PREVIOUS WARMEST YEAR ON RECORD WAS 1998...WHEN THE ANNUAL AVERAGE TEMPERATURE WAS 57.1 DEGREES. THE 2012 AVERAGE TEMPERATURE WAS 2.6 DEGREES ABOVE THE 1981-2010 NORMAL.

2012 WAS THE THIRD WARMEST YEAR ON RECORD FOR BALTIMORE WITH AN ANNUAL AVERAGE TEMPERATURE OF 58.6 DEGREES. ONLY 1931 AND 1949 WERE WARMER WHEN THE ANNUAL AVERAGE TEMPERATURES BOTH YEARS WERE 59.2 DEGREES. THE 2012 AVERAGE TEMPERATURE WAS 3.5 DEGREES ABOVE THE 1981-2010 NORMAL.

December 31 Update: The 42/32 temperatures yesterday and 41/29 today give a final unofficial yearly average of 61.6°, so the record is broken by the higher amount of 1.4°. (Chart updated)

December 29 Update: Today's high of 42° exceeded expectations by 4°, so the gap to a final yearly average of 61.6° has narrowed to less than 0.004°. A miss of Monday's forecast low of 26° could be the clincher.

December 28 Update: Today's +4° temperature departure means the remaining 3 days need to average -0.5° or warmer to clinch a 1.4° excess over the old annual record. The forecast is for a deficit of 2.1°, however.

December 27 Update: Thanks to continued above-average temperatures, a departure of just 1° in the next 4 days would be enough to raise the final yearly average to 1.4° above the old record.

December 25 Update: Yesterday was just the second day this month with cooler than average temperatures (2° below). Today's high outpaced expectations, however, as so many recent days have done. The year-to-date average is outpacing the previous record by 1.3° at 61.9°. With less than a week now remaining, it is now highly likely that the final yearly average will break the record by that amount. The forecast temperatures for the next 6 days average exactly equal to normal, and the average would have to be at least 5° colder in order to avoid a final average 1.3° above the old record. On the other hand, a departure of just +1.2° for the final 6 days would raise the yearly average by another 0.1°.

December 17 Update: Today's low of 48° through 5 pm is 2° above the normal high. At this point, even if temperatures set new record lows and record cold highs for every day in the next 2 weeks, it will still be a record warm year.

December 15 Update: While it's technically not impossible, Washington would now have to set a new record low temperature every day for the next 16 days in order to avoid setting a new record high annual temperature. (See scorecard above.)

December 13 Update: The temperature departure from normal required to avoid setting a new record is now over 22° for every day for the rest of the year. Since that is clearly not happening soon, we are verging on the realm of physical impossibility to avoid a record. The average of all record low temperatures for every day from the 14th through the 31st is -25.5° relative to normal.

December 12 Update: Yesterday's high/low temperatures went virtually midnight to midnight; the final values of 62°/41° averaged out 11° above normal. Today was considerably colder, but the 47°/39° range was still 3° on the warm side. Using the forecast temperatures for the next 7 days and climatology for the remainder of the month yields a projected yearly average of 61.4°. It would have to average almost 21° below normal for the rest of the month in order to avoid breaking the previous record.

Original post:
With just 3 weeks remaining before New Year's Eve, it's becoming increasingly evident that the climate denialists will have to find a replacement for the tired old talking point, "It hasn't warmed since 1998." As the November climate summary showed, 2012 is well on its way to being the warmest on record in the U.S. contiguous 48 states. That will most likely be true in many individual locations as well, particularly in Washington DC.

While well below the record for December 10, today's high of 63° was 15° above average, and the low so far of 49° is a degree above the normal high. This puts the average for the month over 50°, more than 7° above normal to date. If this were to continue through the end of the month (extremely unlikely), it would be the warmest December on record by over 4°.

The year-to-date average temperature of 62.7° is 1.2° above the pace of the previous record warmest year of 1991. If the remaining 3 weeks average just normal (high/low range of 48/34 currently, declining to 44/29 by the 31st), the final 2012 average (marked "Climo" on the charts) will still be 1.1° above the old record. This is a huge amount for a yearly average, as indicated by the top-10 chart, which shows only a 0.9° difference between the current record and the 10th place year of 2002.

It will certainly be colder between now and the end of the month, but how much colder would it have to be to avoid breaking the record? Assuming today's low remains unchanged through midnight, the remaining 21 days of December would have to average an eye-popping -18.1° relative to normal just to tie with 1991. That means an average high for 3 weeks below 30° and an average low below 16°. While such a frigid blast is not physically impossible, it would take an incredibly intense and fanatical belief in the Ice Age Fairy to think that it will happen.

Stay tuned; we'll keep you posted as this historic event unfolds.

Note: While not unexpected, these results were so extreme the the Climate Capitalist suspected that the data monkeys down at Momma Nature's Weather Grill had gotten into the eggnog a bit early. A cross-check of the daily year-to-date values with the monthly averages and a comparison of the projection with a hand calculator confirmed the data, however.

Midsummer Precipitation Review: Who Ya Gonna Call? Drought Busters!

For more posts on Washington, DC temperature and precipitation, see:
Washington DC Weather Records

July 15 Update: As expected, the new Drought Monitor report including data through Tuesday shows little change from last week.

• The Virginia total drought area remains at 85.9%, with the Moderate Drought portion increasing slightly to 37.4%.
• The Maryland total drought area declines to 85.6%, with Moderate Drought down a little to 60.5%.

Original post:
Just when we were getting the "d" word on the brain, the chefs down at Momma Nature's Weather Grill decided to revise the menu. The Washington-Baltimore area has been in the sweet spot for a series of showers and thunderstorms over the last several days. In fact, 5 out of the last 6 days have had measurable rain, and 2 of those had over 1", with over 2" in the 24 hours ending this morning. This brings the Washington July total to 3.77" so far, over 3 times the amount in last year's near-record dry July and a few percent above the normal amount for all of July.

Although lawns and gardens are looking much happier in the short run, the longer-term deficit remains. Five of the 6 months so far this year have been below average. Although March was barely below, February was barely above, so the year-to-date deficit is still 3.42". Furthermore, the heaviest recent rain has been concentrated along the I-95 corridor, so some outlying areas in Maryland and Virginia are still running dry, particularly Southern Maryland, the Eastern Shore and the Northern Neck of Virginia. Even as close as Dulles Airport, the July total is less than half of the Washington National amount. This week's drought report to be issued tomorrow won't include the latest downpours, but conditions should be improved across much of the immediate area.

Here are the regional July precipitation totals to date and monthly/seasonal (since June 1)/yearly departures from average:

Washington National  3.77"/+2.14"/+0.88"/-3.42"
Washington Dulles    1.79"/+0.11"/-2.67"/-2.77"
Baltimore BWI        2.83"/+1.12"/-0.76"/-0.46"
Baltimore Downtown   4.06"/NA/NA/NA 

Images (click to enlarge): July 2010 precipitation percentage of normal through 8 am EDT, July 14, from National Weather Service; Washington, DC 2009-10 monthly precipitation and departures from average, CapitalClimate charts from National Weather Service data

Mid-day update: Marching in Washington

Now
Washington has long been noted for its Marches, and as Josh explains below, this one promises to be every bit as exciting as many in the past. Except for a sun angle more typical of World Series time in October (Did you notice how BRIGHT the snow was Tuesday?), today could easily be mistaken for a mid-January day whose temperature is about 5 degrees below the average for that time of year. Yesterday's high was only 37. That was as cold as, or colder than, 20 days of this past January and all but 2 days of last month. Brisk northwesterly winds gusting up to 30 mph should make it feel even colder than that. The winds are generated by the pressure difference ("gradient") between a large high-pressure area stretching from the upper Midwest all the way to the Gulf of Mexico and the low pressure area which brought our snow on Monday, still spinning over the Maritime provinces of Canada.

How cold can it get in DC in March? The all-time low of 4 was set on the 4th in 1873. On the other hand, the lowest record maximum for any date in March is 77, with an all-time high of 93 on the 23rd in 1907. So, if you want to experience all the seasons in Washington, come back each March, and you'll eventually see just about every kind of weather except tropical storms. Some years, you might even see spring!

At noon, temperatures around the area ranged from 32 at Leesburg to 39 at Culpeper, within a degree or 2 of those at the same time yesterday. Winds were gusting as high as 26 mph. We're on track for a high in the upper 30's and a low tonight about 20.

Tales from the Weather Grill
In our last episode, we revealed some of the secrets behind Momma Nature's management of the Weather Grill. Unfortunately, that wasn't the whole story. In fact, it's downright chaotic there. As we said, she goes out and buys the very best ingredients: crispy cold air, ripe juicy tropical moisture, the liveliest energy ("vorticity") available. She hires the most skilled technicians to develop partial-differential equations and program them into the tastiest recipes. But then, something seems to go terribly wrong. Perhaps she forgets where she put the recipe and leaves the ingredients sitting around until they spoil and have to be thrown out. Maybe she rushes around too fast and everything turns out undercooked. Or, she mixes the ingredients, puts them into the oven, and then spends so much time talking on her cell phone to the other goddesses that she doesn't hear the timer go off, and dinner is burned beyond all recognition. What can you do? She's a quirky lady, but she's the only Nature we've got. Even though we keep complaining, snow fans or snow-haters alike, we love her anyway, and we keep coming back to see what she's dishing out today. If you don't like your meal, please don't complain to us. We don't cook it; we only interpret the menu from the clues Momma gives out. If you want, you could try filing a report at Zagat's.

Washington Wacky Winter Weather Wimpiness
Recent discussion of the wimpiness of Washington's response to winter weather (or the threat thereof) reminded me of the fast-food commercial of a decade or so ago which went something like this:
Geezer 1: "When I was a kid, we had to walk to school 10 miles in the snow. And it was uphill both ways. In fact, we didn't even have shoes on our feet."
Geezer 2: "Feet, you had feet?"

Storm updates...

Nowcast

1:00pm: At 12:30, radar showed snow continuing across the DC metro area, with additional snow extending to the southwest to well south of Charlottesville, which was reporting light snow. This area of snow was moving generally toward the northeast. The rain/snow line has remained fairly steady since early morning just north of Richmond on I-95 and extending northeastward. Ft. Belvoir was reporting moderate snow and the other local reporting stations had light snow. Besides Charlottesville, other VA stations reporting snow included Staunton and Lynchburg with light snow and Roanoke with moderate snow. In MD, snow was light at Baltimore and Andrews AFB, moderate at Annapolis. The wind at Cape Hatteras was from the north-northwest and the barometer was steady, indicating that the storm continues to move gradually away.
We will continue to see snow through the afternoon in most of the area. Depending on the intensity of the precipitation and the amount of mixing with sleet or rain, snowfall amounts will be on the low end of our predictions.
Scroll down to the bottom of Jason's post below for the latest on closings and other useful links.

Background

Here's a dirty little secret: Momma Nature runs a sloppy kitchen down at her Weather Grill. She hasn't been cited for any code violations lately, not since she got that honking new supercomputer to help keep track of things, but it does get a bit out of hand there at times. The staff is very temperamental, and they don't always see eye to eye. It was an especially rowdy scene recently. All weekend long, the European chefs were arguing with the American ones over which recipe to use. The ingredients were on hand in large quantities for an exceptional meal, the biggest event of the season in the mid-Atlantic region:

• crispy cold air
• ripe, juicy tropical moisture
• some of the liveliest vorticity (energy) on the planet

But, there was hot dispute over exactly what to prepare. The Europeans were in favor of a more wintry menu, with low pressure staying off the coast and colder air giving snow for us. The Americans favored a more traditional springtime menu, with the low pressure area moving inland and warmer air giving us rain. Tempers flared; the Europeans became so upset that they began threatening to keep the low so far out to sea that there wouldn't be enough heavy snow to satisfy all the customers who had made reservations because they were counting on a snow day. As time wore on, though, the Europeans began to convince the Americans of their point of view. Finally, Momma herself stepped in to settle things once and for all, but it was too late to get new menus printed with all the latest details. We'll just have to listen carefully as the waitpersons recite the daily specials.

We'll keep you continually updated as things develop. Remember our motto, "We keep hitting the page reload button so you don't have to!"

However the forecast turns out from your point of view, here's a bit of humor from the Washington Post's Style Invitational contest:
What's the definition of "Chiropractors-Christmas", taken from a page heading in the Yellow Pages directory?
"A forecast of freezing rain and heavy, wet snow."

History

11:30am: At 11am, radar showed snow continuing across the DC metro area. Rain and showers were over the lower Chesapeake Bay and middle Eastern Shore. None of the official reporting stations in the immediate area were reporting anything heavier than light snow, but Charlottesville, Staunton, Lynchburg and Roanoke in VA all had moderate snow. In west-central Montgomery County, grassy areas are whitish, but mostly green/brown; streets are wet. Temperature has dropped about 1/2 a degree to just a bit above 32. The wind at Cape Hatteras was straight north and the barometer had stopped falling at 29.27" (991 mb). This indicates that the storm is beginning to move away from the coast.
10:00am: At 10am, radar shows snow continuing to break out across the DC metro area. At the official reporting stations, flurries at 9am had become light to moderate snow, with visibilities as low as 1/2 mile reported at Ft. Belvoir. Here in west-central Montgomery County, a light flurry which began shortly before 8 has given way to steadier and heavier snowfall, enough to moisten the pavement and begin to whiten some bare ground in the last 15 minutes. Temperature is just a fraction below 33. One interesting spot to watch as this storm continues to develop is Cape Hatteras, which has been reporting strong NE to NNE winds. The barometer there continues to drop at a pretty good rate, down 5 mb (.15") in the last 3 hours to 991 mb (29.27").

Mid-day update: Do not break arm patting self on back :)

How about that classic DC President's Day snow storm? What snow, you ask. Well, there were at least 10 or 12 lonely flakes drifting down mid-afternoon yesterday. If you blinked, you probably missed them, but our hawk-eyed observers kept you up to date. After some light rain during the night, the sun broke through the overcast about 9-10 am this morning, and temperatures are headed well up into the 50's in the metro area, depending on the amount of sun we get. Despite a nominal mostly high overcast, at 1pm temperatures in the immediate area ranged from a low of 50 at Quantico to 59 at Stafford and Culpeper. Fredericksburg VA had already reached 61 by noon and 63 at 1pm. There is still the chance of some showers as a complex low pressure area moves through the Northeast and a cold front approaches from the west. There is currently a strong squall line moving through Tennessee, but that will not be reaching our area.

As Jason has already noted, the CapitalWeather team did an excellent job handling the latest storm system. As I indicated in my Friday pm update, there were already signs that snow, if any, would change to rain, and we updated the outlook through comments and postings through the weekend. My reasoning for being skeptical of snow was the following:

When I was but a wee lad in the shire long, long ago and far, far away I learned an important lesson in the kitchen of Momma Nature's Down East Weather Grill (besides "Don't mess with Momma!"). That was that the secret sauce absolutely required to cook up a nice batch of fluffy snow is . . . Are you ready for this? COLD AIR! It's all very nice to have a shot of cold air come in during the week, and there's the mountain factor contributing to cold air damming, which the models still can't get a good handle on, but there also needs to be some support from the upper-air flow for this to happen. I just didn't see that without any kind of trough along the east coast, and none was predicted by the models, either. The official minimum temperature for DC turned out to be 35 last night. Another clue was Kevin's comment which noted the breakout of precip in IL and KY Saturday way ahead of the development of the surface low back a few states. This was an indication that the juicy tropical moisture previously pumped in by the low off California was racing ahead of the necessary vertical motion, which, of course, is another crucial ingredient in cooking up precip, whether frozen or not. Note that DCA eventually received a whopping 0.06" of precipitation in the 24 hours ending at 7am today. Even if all of that had been frozen, the depth would have been way less than an inch.

So, hopefully without sounding more like a geezer than I already am, let me say that we have already seen several times this winter that the models are great as far as they can go, but there is still a role for good old-fashioned synoptic analysis: Look at the actual data and interpret what is going on in terms of hard-earned experience. I expect I will have more to say on this subject as time goes on.

News items
The Washington Post reports this morning on a memo expressing concern over the effects of National Weather Service budget cuts.

The American Association for the Advancement of Science reported at its annual meeting in Washington on Thursday that "ocean temperatures are rising because of human activity, and the global impact could be severe".
There was also a report that aging in the brain can be slowed; perhaps there is hope for the geezer weather guy after all!