Hype-ocracy PM Update

6 PM Update: The afternoon model run is consistent with the morning one in showing a low pressure area tracking to the south of the area and bringing Washington snow on Christmas.

See here for an example of how snowfall amounts are not necessarily correlated with temperatures.

Original post:
The eyeball-hungry low-fiber WaPo has pimped the "s-word" in six seven consecutive [11 pm Update] 8 out of the last 9 blog headlines, but the broadcast media have been maintaining a sensibly low profile on the chances for Washington snow on Christmas. In today's mid-day sample, WRC, Channel 4, veteran Tom Kierein mentioned the possibility of Washington snow on Christmas, but reined in the hype. Even frequent hyper-personality Tom Sater on WUSA, Channel 9, cautiously backed off the assertions last night of newcomer Anny Hong.

The National Weather Service, while carrying a 50% chance of Washington snow on Christmas, is being respectful of the uncertainty at the limits of practical predictability:

LATEST GUIDANCE CONTINUES TO BE IN GOOD AGREEMENT WITH LOW PRESSURE IMPACTING THE REGION SOMETIME FRIDAY AND SATURDAY. THERE STILL REMAINS A GOOD DEAL OF UNCERTAINTY WITH THE TRACK AND DEVELOPMENT OF THE SYSTEM. IF THE LOW TRACKS CLOSER TO THE COAST...SIGNIFICANT SNOW IS POSSIBLE DURING THIS TIME. HOWEVER...IF THE TRACK OF THE LOW REMAINS WELL OFF THE COAST...SNOWFALL WILL BE LIGHT. ALL INTERESTED PARTIES SHOULD DEFINITELY STAY APPRISED OF THE LATEST FORECASTS AS WE GET CLOSER TO THIS POTENTIAL EVENT.

The map to the right shows one major model's interpretation of the surface weather for 7 pm, Saturday, December 25. It has a strengthening storm off the Mid Atlantic coast, with snow over much of the DMV (DC/Maryland/Virginia). If interpreted literally (a serious risk at the range of 5 and a half days), it would generate a total for the event of about 3-5" of snow in the region, with the larger amounts in the southern and eastern portions.

The graph shows snow depth on the ground in Washington on Christmas for each year since 1929. By the way, the 7" last year, while tying the record for the period, had completely disappeared the next day. Note to Ice Ager Linkbot Tom N: If you can find a trend in that data, you deserve to beat out Fred the Singe-r for the Nobel Prize in Cherry Picking.

Hype-ocracy: White Christmas in Washington

In a town normally overrun with hype, the hyping of Washington snow on Christmas reaches even more extreme heights. With the event still 6 days away, the possibility of Washington snow on Christmas has once again appeared among the blogotariat and the ratings-driven media. The chances of Washington snow on Christmas was featured on at least 3 local TV channels (WTTG-5, WJLA-7, and WUSA-9) tonight; WRC-4 was delayed by the football game too late to make this survey.

In fact, this year the cold air is firmly entrenched, but that didn't prevent the earlier outlook for Washington snow [the week before] Christmas to be a complete bust today. Some previous indications of the white stuff for Tuesday have also trended strongly toward the bust-bucket. Nevertheless, some models are hinting at the possibility of a storm developing late in the week and bringing some Washington snow on Christmas.

Three years ago, CapitalClimate surveyed the climatological prospects for Washington snow on Christmas:

Climatologically, there is only about a 10% chance of 1" or more of snow on the ground on Christmas in Washington. Since 1929, there have been only 8 such occurrences. The largest amount was 7" in 1966, with 5" and 4" in 1962 and 1963, respectively. That was the only time it happened in consecutive years. The most recent was 1989, with 2". The wettest was 1.41" of rain in 1945.

Since that time, there has been one more year with Washington snow on Christmas. That was, of course, 2009, when 7" remained on the ground from the 16" which fell on the 18th-19th. That marked the first time there had been Washington snow on Christmas in 20 years. If there is Washington snow on Christmas again this year, it would be only the second time that had occurred in consecutive years since 1929.

As for Washington snow on Christmas resulting from measurable snow falling on the actual day of December 25, that's only happened 6 times in 81 years (7.4%), and only 2 of them were over 1". Here's the complete list:

1962 5.4
1969 4.3
1935 0.6
1970 0.3
1993 0.2
2002 0.2 

Still dreaming of Washington snow on Christmas? The odds are certainly better this year than the climatological average, but tonight's glib pronouncement of a "50-50 chance" for Washington snow on Christmas by Washington novice Anny Hong on WUSA, Channel 9, was waaaay premature.

Image (click to enlarge): Washington snow on Christmas (amount falling on December 25) since 1929; CapitalClimate chart from NWS data

Season's Greetings

Greetings of the season, from MIT TechTV's animated snow globe (click arrow below to play; adjust speakers, volume may be loud):

Syracuse Snowfall Smashes Monthly Max

Images (click to enlarge): December 19, 2010, snow depth and departure from normal, from National Weather Service



The 1.4" of snow which fell at Syracuse, NY on Friday, December 17, brought the monthly total so far to 70.9". This is the highest amount ever recorded in December at Syracuse. The old record was 70.3" in 2000. Aided by a persistent northwesterly wind over an unfrozen Lake Ontario, snow has fallen on all but 4 days so far this month. Six inches or more fell on each of 4 consecutive days from the 5th through the 8th, and there have been 3 days with at least 10" each.

With a little less than 2 weeks left, this month is now within 0.1" of tying the 4th highest monthly total in Syracuse history dating back to 1902:

1. 78.1 INCHES JANUARY 2004
2. 72.6 INCHES FEBRUARY 1958
3. 72.2 INCHES JANUARY 1978
4. 71.0 INCHES JANUARY 1966
5. 70.9 INCHES DECEMBER 1ST-18TH, 2010 

The latest forecast indicates that the greatest chance for more snowfall in the coming week is a 50% probability of snow showers on Monday.

The December average temperature of 26.2° so far at Syracuse, while 4.4° below average, is not even within 5° of being in the top 5 coldest Decembers. The coldest on record was 14.7° in 1998.

Today's snow depth map for the Northeast from the National Weather Service shows heavy amounts in the lee of the Great Lakes and in the Adirondacks and mountains of northern New England, but little or nothing along the coast and most interior sections.

Arctic Air Attack Registers Records; Precipitation, Not Temperature, the Real Story

It was noted here recently that heat records have far exceeded cold records in the U.S. for the last 9 consecutive months. Nevertheless, the recent outbreak of Arctic air as far south as the Gulf Coast and Florida has inspired the Ice Agers to Twitch far and wide, "Hundreds of new cold and snow records set in the USA." The heavy snowfall in Minneapolis even led to the collapse of the inflatable roof of the Metrodom [sic].

Is the oft-proclaimed, but never observed, New Ice Age upon us? Well, not quite yet. With the month of December almost half over, the new daily low temperature records have exceeded the new daily highs by a margin of 378 to 191. For the year to date, however, the heat records still exceed the cold records by 7068. At the current rate, the cumulative cold records will catch up to the hot ones in about 491 days, or a little over 16 months.

As usual, focusing on the short term obscures the true picture. Leaving aside the fact that the area of the entire U.S. is less than 2% of the area of the Earth, the latest available December month-to-date average temperature (through the 12th) shows that more of the country is near to above normal than below. Furthermore, the areas with the heaviest snow are not particularly cold.

As was the case with the Mid Atlantic blizzards of last winter, the story here is not temperature, but rather precipitation. The number of daily precipitation records so far in December is 1036, nearly 3 times the number of cold records. On December 1 alone, for example, 334 precipitation records were set, nearly as many as the cold records for the entire month to date. On Sunday, the 12th, the day of the Metrodome collapse, 192 precipitation records were set, vs. only one temperature record. That's right, Jamestown Muni Airport in North Dakota (KJMS) recorded a low of -20°F, surpassing its previous record of -16°F set in 1960. Meanwhile, 13 stations in Minnesota alone were setting daily precipitation records, 5 of them with histories of over 110 years.

Images (click to enlarge): Cumulative excess of daily high temperature vs. low temperature records since Jan. 1, 2010; Total daily temperature and precipitation records Dec. 1-13, 2010; U.S. monthly average temperature departure from normal through Dec. 12. CapitalClimate charts from National Climatic Data Center data, NCEP/NOAA data via ESRL.

Syracuse Snowless String Snapped Sharply

The National Weather Service reports that the 1" of snow which fell at Syracuse, NY on December 3 ended a string of 280 days with less than an inch of snow which began on February 26. This was 7 days less than the record of 287 days from February 26 to December 8 last year.

Since that first snowfall of the season, Syracuse has set 3 consecutive daily snowfall records:

Date    Amount  Old Record Year
Dec. 6   12.2"   8.8"      2000
Dec. 7    9.3"   7.0"      1958
Dec. 8   14.9"   8.9"      1961 

Through Dec. 9, measurable snow has now fallen at Syracuse every day this month except for the 2nd. The monthly total so far of 47.7" is over 50% above the average December total of 28.6". On the other hand, this is still well below the top 5 snowiest Decembers since 1950:

1. 70.3  2000
2. 64.6  1989
3. 52.9  2005
4. 52.5  1969
5. 51.9  1970 

The December daily snowfall record at Syracuse is 18.6", set on the 30th in 1997. The annual average snowfall is 121.1".

Another extended bout of lake-effect snow is likely next week.

As of last evening, NWS reports show 5-day storm totals approaching 5 feet in a few places:

********************STORM TOTAL SNOWFALL 12/4-12/9/2010****************

LOCATION          STORM TOTAL    TIME/DATE    COMMENTS
                     SNOWFALL       OF
                     (INCHES)   MEASUREMENT


NEW YORK

...BROOME COUNTY...
   BINGHAMTON REG        21.7   700 AM  12/9 BINGHAMTON AIRPORT
   WHITNEY POINT         16.8   700 AM  12/9 COCORAHS 1.7 SSE
   WINDSOR               13.4   700 AM  12/9 COCORAHS 8 SE
   CHENANGO FORKS        11.1   700 AM  12/9 COCORAHS 3 SE
   BINGHAMTON             8.4   700 AM  12/9 COCORAHS 1.8 SW
   VESTAL                 7.9   700 AM  12/9 COCORAHS 2.8 SSE

...CAYUGA COUNTY...
   AUBURN                20.3  1023 AM  12/9 COOP
   CAYUGA                16.0   700 AM  12/9 COCORAHS 3.2 ESE
   AUBURN                15.6   700 AM  12/9 COCORAHS 8.3 SSE
   LOCKE                 13.3  1029 AM  12/9 COOP

...CHEMUNG COUNTY...
   VAN ETTEN              1.6   700 AM  12/9 COCORAHS 0.3 ENE

...CHENANGO COUNTY...
   SHERBURNE             28.3   700 AM  12/9 COCORAHS 3.6 NNE
   SHERBURNE             16.2  1030 AM  12/9 COOP
   NORWICH                8.1   700 AM  12/9 COCORAHS 5.4 W

...CORTLAND COUNTY...
   FREETOWN              15.0  1001 AM  12/9 COCORAHS
   MCGRAW                15.0   700 AM  12/9 COCORAHS 5.2 SE
   WILLET                14.8   700 AM  12/9 COCORAHS 1.8 E
   MARATHON              13.1   700 AM  12/9 COCORAHS 1 NW
   MARATHON               8.6   700 AM  12/9 COCORAHS 0.7 WSW

...DELAWARE COUNTY...
   HAMDEN                12.3  1005 AM  12/9 COCORAHS

...MADISON COUNTY...
   FENNER                50.6   827 AM  12/9 SPOTTER
   CAZENOVIA             48.7   838 AM  12/9 SPOTTER
   MORRISVILLE           35.2  1040 AM  12/9 COOP MRRN6
   MUNNSVILLE            32.0   700 AM  12/9 COCORAHS 2 SW
   LAKEPORT              26.5   700 AM  12/9 COCORAHS
   CAZENOVIA             25.8   700 AM  12/9 COCORAHS 2.9 SE
   EARLVILLE             19.7   700 AM  12/9 COCORAHS 0.4 W
   CANASTOTA             16.8   700 AM  12/9 COCORAHS 0.9 S
   ONEIDA                15.4   700 AM  12/9 COCORAHS 0.7 NNE

...ONEIDA COUNTY...
   DURHAMVILLE           17.9   700 AM  12/9 COCORAHS 3.5 NNW
   VERNON                17.8   700 AM  12/9 COCORAHS 0.4 NNW
   POINT ROCK            15.5   700 AM  12/9 COCORAHS 0.6 SE
   NEW HARTFORD          10.6   700 AM  12/9 COCORAHS 0.8 S
   STOKES CORNER         10.2   700 AM  12/9 COCORAHS 1.4 NE
   LAKE DELTA            10.1  1031 AM  12/9 COOP
   WHITESBORO             8.9   700 AM  12/9 COCORAHS 3.9 NE
   ROME                   7.8   700 AM  12/9 COCORAHS 4.8 SSE
   WESTERNVILLE           7.7   700 AM  12/9 COCORAHS 2 NW
   WESTMORELAND           7.6  1030 AM  12/9 SPOTTER
   HOLLAND PATENT         7.4   700 AM  12/9 COCORAHS 1.5 WSW
   BOONVILLE              3.5  1032 AM  12/9 COOP
   BOONVILLE              3.3   700 AM  12/9 COCORAHS 8 E
   MARCY                  2.0   804 AM  12/9 COCORAHS

...ONONDAGA COUNTY...
   DE WITT               58.2   700 AM  12/9 COCORAHS 1.4 WSW
   SYRACUSE              58.2  1009 AM  12/9 COCORAHS
   LIVERPOOL             54.7   700 AM  12/9 COCORAHS 3.1 N
   CLAY                  52.1   700 AM  12/9 COCORAHS 4.6 NW
   VILLAGE GREEN         49.6   700 AM  12/9 COCORAHS 2.6 ESE
   SYRACUSE              46.1   500 PM  12/9 SYRACUSE AIRPORT
   CAMILLUS              45.2   700 AM  12/9 COCORAHS 1 W
   CLAY                  44.2  1010 AM  12/9 COCORAHS
   FAYETTEVILLE          40.4   700 AM  12/9 COCORAHS 1.6 W
   MARCELLUS             36.1   700 AM  12/9 COCORAHS 1.6 E
   BREWERTON             34.4   700 AM  12/9 COCORAHS 1.5 ESE
   SYRACUSE              33.8   700 AM  12/9 COCORAHS 1.4 SE
   BREWERTON             23.5  1032 AM  12/9 COOP BWTN6
   JAMESVILLE            22.3  1012 AM  12/9 COCORAHS
   POMPEY                22.3   700 AM  12/9 COCORAHS 2 NNW
   TULLY                 17.0   700 AM  12/9 COCORAHS 1.7 WSW

...OTSEGO COUNTY...
   HARTWICK              18.8   700 AM  12/9 COCORAHS
   WORCESTER             18.5   700 AM  12/9 COCORAHS 4 SSW
   COOPERSTOWN           17.6   700 AM  12/9 COCORAHS 0.3 S
   UNADILLA FORKS        16.8  1014 AM  12/9 COCORAHS
   RICHFIELD SPRINGS     13.5   700 AM  12/9 COCORAHS 0.5 ESE
   MARYLAND              10.9  1033 AM  12/9 COOP
   NEW BERLIN             6.0   900 AM  12/9 COCORAHS 

Image (click to enlarge): Clinton Square in downtown Syracuse, Wednesday morning (Dec. 8), from Syracuse Post-Standard.

Drought Dispatch: Florida's Fall Increased Intensity

The latest U.S. Drought Monitor report shows that the intensity of the ongoing drought increased in Florida through the last reporting week of November and the end of meteorological fall. As of November 30, only 4% of the state (in the extreme southeast) was free of drought conditions, down from 8% the previous week and 74% at the beginning of autumn. The portion of the state in Extreme Drought (Category D3), the second highest category, was 8%, up from 2% the previous week.

Dry conditions in Florida began to become established in mid summer, and they have steadily increased since then. Although percentages of normal precipitation increased somewhat in November from October's ultra bone-dry levels, particularly in a small area on the southwestern coast and panhandle, they were well below 75% over much of the state.

November precipitation was substantially substandard in most of east-central Florida. The National Weather Service (NWS) reports that the measurable rainfall on November 2 ended a 34-day dry spell at both Orlando and Melbourne. This was the 4th longest rain-free stretch at Orlando on record and the 5th longest at Melbourne. Melbourne was the only major reporting station in the region to report above-average rainfall for the month. The total of 4.62" for the autumn season at Daytona Beach was a new record low, surpassing the 5.37" in 1925.

STATION           NOV 2010      30 YEAR   DEPARTURE     PERCENT OF
                  RAINFALL      NORMAL    FROM NORMAL     NORMAL

DAYTONA BEACH      0.95"         3.03"      -2.08"           31%
(DAB)
ORLANDO            1.68"         2.32"      -0.64"           72% 
(MCO)
MELBOURNE          3.43"         3.12"      +0.31"          110% 
(MLB)
VERO BEACH         2.43"         3.04"      -0.61"           80% 
(VRB)
CLERMONT           1.67"         2.40"      -0.73"           70% 
(CLRF1)
DELAND             1.74"         2.72"      -0.98"           64%    
(DELF1)  
SANFORD            1.37"         2.96"      -1.59"           46% 
(SFNF1)
TITUSVILLE         1.71"         3.45"      -1.74"           50% 
(TITF1)
FORT PIERCE        1.38"         3.50"      -2.12"           39% 
(FPCF1)
STUART             2.29"         4.23"      -1.94"           54% 
(STRF1)  

Images (click to enlarge): Florida drought monitor for November 30, 2010 from USDA/NOAA--intensity ranges from D0/Abnormally Dry (yellow) through D3/Extreme Drought (red); Florida percent of normal precipitation for October and November 2010, from National Weather Service