Thursday, August 20, 2009

Mid-Atlantic Drought Update

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


After diminishing earlier in the summer, minimal drought has crept back into much of the Washington-Baltimore region. D0 (Abnormally Dry) conditions have jumped this week from 17% to nearly half of the state of Virginia. In Maryland, the D0 area has increased from 48% to 54% of the state.

Through Aug. 20, monthly rainfall at Washington National is less than 50% of average, and seasonal rainfall since June 1 is a little more than 1" in deficit. As of 5 pm today, monthly/seasonal/yearly totals in the area are:
Washington National 0.92"/7.85"/25.12"
Washington Dulles 0.41"/9.28"/29.06"
Baltimore (BWI) 1.52"/10.33"/29.61"
Images (click to enlarge): Maryland and Virginia weekly drought conditions from U.S. Drought Monitor (NOAA/USDA)

Wild William Wanes, Waxes
Hurricane Bill Fluctuates in Strength, Threatens Bermuda, Maritimes

After having reached Category 4 with maximum winds of 135 mph, Hurricane Bill weakened to as low as 120 mph this morning and is now back up to 125 mph. The storm continues on a path which should take it between the East Coast of the U.S. and Bermuda, then close to Nova Scotia and Newfoundland. At 5 pm, the Bermuda Weather Service upgraded its Tropical Storm Watch to a Warning, and a Hurricane Watch is also in effect. High waves and dangerous rip currents are likely to affect Bermuda and much of the U.S. East Coast in the next couple of days.

The storm is moving steadily northwest at 18 mph from a position a little less than 600 miles south of Bermuda. A more northerly turn is expected by Saturday.

Image (click to enlarge): Hurricane Bill forecast track from National Hurricane Center

Wednesday, August 19, 2009

Thoughts on Climate Science and Skepticism

As a response to a discussion at the Canadian political blog BigCityLib (BCL), a CapitalClimate visitor left a comment yesterday regarding the state of climate science as depicted in the 20 "Climate Tutorials" links in the left margin of this page. In essence, he said,
I find that the evidence is still underwhelming. . . Primarily, what Im looking for is empirical evidence (which excludes computer models) which links human CO2 with catastrophic warming.
I started to write a comment in reply, but I found that it raises a number of issues about the relationship of science, skepticism, and political policy, so I decided to make a separate post out of it:

Well, thanks for stopping by. I'm sorry you couldn't find what you were looking for. I'm sure the thousands of scientists who have worked for over a century on this problem are even more disappointed. The simple fact is that the science is what it is, whether or not you or anyone else likes it (or more importantly the policy implications). Like any branch of science, there are always some uncertainties involved. Whether those uncertainties are sufficient to preclude policy action is, however, a political question, not a scientific one. Although there are some legitimate scientific concerns, by and large these have been hijacked and used dishonestly for political purposes. (That was behind the original point of the BCL post.)

I have personally paid country club prices to see Lindzen present his position. FWIW, I'm confident he's sincere, but his "iris" hypothesis is just that, a proposal subject to testing. His theory, however, has been widely found by objective observers to be not supported by the evidence (one recent example here).

The Roger Pielkes (there are 2 of them, Jr. and Sr., although some might argue that there are in fact more), have made careers out of self-referential contrarianism. In the case of Jr., this has frequently taken the form of reckless charges of plagiarism, theft, bias, and fraud, all the while cloaking himself in the presumably infallible role of TheHonestBroker™. Their latest effort is meeting with legitimate skepticism on scientific grounds, but that has certainly not deterred the deniosphere from attempting to make political hay out of it.

As a degreed scientist with a minimal knowledge of physics, I find modern particle physics to be too complicated, confusing and counter-intuitive. However, I'm not wasting my time going around to physics forums denouncing the science and its practitioners as commie-pinko-enviro-nazis. Why is it, then, that climate science does provoke such reactions, even among Meteorologists Who Should Know Better? One of the meanings behind the name of this blog is that climate science, through its policy implications, has been inextricably linked to financial and economic issues. Once money comes into the picture, people get very crazy very quickly, and if large amounts of it are involved, even crazier; just look at the recent financial market insanity for proof.

So, the bottom line here is that anyone is entitled to their own opinion, but that doesn't make it science, even if the proponent has the outward trappings of a scientist. Given the economic and political subtext of the discussion, it's not only fair but necessary to ask, "What are the financial and ideological motivations behind what is being said?"

Global warming theory is based on the CO2 greenhouse effect which was discovered over a century ago. I have a more-than-50-year-old atmospheric physics text on my shelf which describes and quantifies it quite well. The development of the computer models the deniosphere so loves to hate (Not Computer Models) has simply added more support to the underlying principles. These and other subsequent analyses have continued to improve confidence in the theory to the point that many scientists involved in the field have called for policy actions to limit the potential negative effects of increased greenhouse gas emissions. They have done this not only individually in some cases, but also through such organizations as scientific societies (including the AMS and AGU), the IPCC, and various national science academies. That has provoked a strong reaction from some who have a vested interest in inaction. A realistic debate about policy choices is one thing, but fraudulent smearing of the science and its practitioners is something else again. The proper response to those tactics is what BCL was discussing. I would call that true skepticism.

Monday, August 17, 2009

Austin's Hottest Summer To Date

For the latest record temperature posts, see:
Record Heat
Record Cold


The extreme summer heat and drought in Texas continue to set records. Through Aug. 16, this is the hottest summer on record in Austin (records since 1854) and San Antonio (since 1885). The averages exceed the previous records by over 1°. Del Rio is having its third hottest summer since 1906. Austin and Del Rio have also had 14 consecutive days of 100° temperatures through yesterday, and San Antonio had 12 consecutive 100°+ days through the 12th. As of 3 pm CDT today, the temperature is 97° in Austin and 98° in both San Antonio and Del Rio. Here are the details from the National Weather Service:
JUNE 1ST TO AUGUST 16TH...2009 WAS THE WARMEST  
JUNE 1ST TO AUGUST 16TH AT AUSTIN MABRY AND SAN ANTONIO...AND
THE 3RD WARMEST AT DEL RIO. JULY 2009 WAS THE WARMEST JULY AND
MONTH FOR AUSTIN MABRY AND SAN ANTONIO. THE TABLE BELOW COMPARES THE
AVERAGE TEMPERATURE FOR JUNE 1ST TO AUGUST 16TH...2009 WITH THE
WARMEST JUNE TO AUGUST PERIODS FROM THE PAST.

AUSTIN MABRY WARMEST JUNE 1ST TO AUGUST 16TH PERIODS FROM
DAILY CLIMATE DATA FROM 1898 TO 2009...A 77 DAY PERIOD

1. 88.4 JUNE 1 TO AUGUST 16...2009
2. 87.2 JUNE 1 TO AUGUST 16...2008
3. 87.0 JUNE 1 TO AUGUST 16...1998

AUSTIN MABRY WARMEST JUNE TO AUGUST PERIODS FROM MONTHLY DATA
FROM 1854 THROUGH 2008.

1. 86.7 JUNE TO AUGUST 1998 AND 2008
2. 86.2 JUNE TO AUGUST 1925 AND 1980
3. 86.1 JUNE TO AUGUST 1923
4. 85.8 JUNE TO AUGUST 1956 AND 2006
5. 85.7 JUNE TO AUGUST 1886...1918 AND 1954

SAN ANTONIO WARMEST JUNE 1ST TO AUGUST 16TH PERIODS FROM
DAILY CLIMATE DATA FROM 1885 TO 2009...A 77 DAY PERIOD

1. 87.9 JUNE 1 TO AUGUST 16...2009
2. 86.7 JUNE 1 TO AUGUST 16...1998
3. 86.6 JUNE 1 TO AUGUST 16...1980

SAN ANTONIO WARMEST JUNE TO AUGUST PERIODS FROM MONTHLY DATA
FROM 1885 THROUGH 2008.

1. 86.2 JUNE TO AUGUST 1980 AND 1994
2. 86.0 JUNE TO AUGUST 1998
3. 85.9 JUNE TO AUGUST 2006
4. 85.6 JUNE TO AUGUST 1962
5. 85.4 JUNE TO AUGUST 1990

DEL RIO WARMEST JUNE 1ST TO AUGUST 16TH PERIODS FROM DAILY CLIMATE
DATA FROM 1906 TO 2009...A 77 DAY PERIOD

1. 89.9 JUNE 1 TO AUGUST 16...1998
2. 89.8 JUNE 1 TO AUGUST 16...1953
3. 88.9 JUNE 1 TO AUGUST 16...2009

DEL RIO WARMEST JUNE TO AUGUST PERIODS FROM MONTHLY DATA FROM 1906
THROUGH 2008

1. 88.7 JUNE TO AUGUST 1998
2. 88.5 JUNE TO AUGUST 1953
3. 88.4 JUNE TO AUGUST 2001
4. 87.8 JUNE TO AUGUST 1951
5. 87.6 JUNE TO AUGUST 1996

AUGUST 16TH WAS THE 14TH 100 DEGREE DAY IN A ROW AT AUSTIN MABRY AND
DEL RIO. FOR THE FIRST 16 DAYS OF AUGUST 2009 SAN ANTONIO HAD 12 100
DEGREE DAYS IN A ROW FROM THE 1ST TO THE 12TH. THE TOTAL 100 DEGREE
DAYS FOR 2009 SO FAR ARE AS FOLLOWS...57 AT AUSTIN MABRY...46 AT
AUSTIN BERGSTROM INTERNATIONAL AIRPORT...54 AT DEL RIO...
50 AT SAN ANTONIO INTERNATIONAL AIRPORT...AND 60 AT SAN ANTONIO
STINSON FIELD.

IN SOME YEARS...NO 100 DEGREE DAYS WERE OBSERVED. IN THE 1970S...
SAN ANTONIO DID NOT HAVE ANY 100 DEGREE DAYS FROM 1972 TO 1977...AND
IN 1979. IN THE 1970S AUSTIN DID NOT REPORT ANY 100 DEGREE DAYS IN
1973...1975 AND 1979...AND DEL RIO HAD NO 100 DEGREE DAYS IN 1976.
IN 2007 DEL RIO AND SAN ANTONIO DID NOT REPORT ANY 100 DEGREE
DAYS...WHILE AT AUSTIN FOR 2007 THERE WERE 3 100 DEGREE DAYS.

SO FAR IN THE SUMMER OF 2009...EXTREME ALL TIME MONTHLY HIGHS
HAVE NOT BEEN OBSERVED YET...HOWEVER A FEW RECORD DAILY HIGHS AND
RECORD DAILY WARMEST EARLY MORNING LOWS HAVE OCCURRED. THE HEAT FOR
THE SUMMER OF 2009 HAS BEEN OF LONG DURATION...NEARLY CONTINUOUS
FROM EARLY JUNE THROUGH AUGUST 16TH. THE DRYNESS ACROSS THE AREA
SINCE SEPTEMBER 2007 HAS CONTRIBUTED TO THE HEAT THIS SUMMER.
IN THE DRY PERIOD 100 YEARS AGO...THE HIGH OF 107 AT SAN ANTONIO
ON AUGUST 20...1909 WAS THE WARMEST ALL-TIME HIGH UNTIL
AUGUST 19...1986 WHEN THE HIGH WAS 108 AND SEPTEMBER 5...2000...WHEN
THE HIGH WAS 111. DURING THE DRY PERIOD IN 1988...DEL RIO HAD AN
ALL-TIME HIGH OF 112 ON JUNE 12...1988...THAT STILL STANDS TODAY.
AT AUSTIN MABRY THE OLD ALL-TIME HIGH OF 109 JULY 26...1954 AND
AUGUST 18...1923 WAS DURING DRY PERIODS...AND WAS LATER EXCEEDED BY
THE HIGH OF 112 SEPTEMBER 5...2000...IN THE LATE AUGUST TO EARLY
SEPTEMBER OF 2000 HEAT WAVE.

THE HOTTEST DAYS THIS YEAR AS OF AUGUST 16TH ARE LISTED BELOW.

LOCATION HOTTEST DAYS AND DATE

AUSTIN MABRY 106 JUNE 25...JUNE 29...AND JULY 8
AUSTIN BERGSTROM 107 JUNE 25
BURNET 103 JULY 8...JULY 9...AND JULY 16
DEL RIO 107 MAY 6
FREDERICKSBURG 101 JUNE 25...JULY 8...AND JULY 9
HONDO 105 JULY 5 AND JULY 8
KERRVILLE 104 JUNE 29...JULY 5...JULY 8...AND JULY 9
LA GRANGE 105 JUNE 25
LLANO 106 JULY 16 AND 26...AUGUST 5...6...AND 11
NEW BRAUNFELS 107 JUNE 25
PLEASANTON 104 JULY 5 AND AUGUST 12
ROCKSPRINGS 100 JULY 8 AND JULY 9
SAN ANTONIO 104 JUNE 29...JULY 5...JULY 8...AND JULY 9
SAN ANTONIO STINSON 107 JULY 5
SAN MARCOS 106 JUNE 25...JUNE 29...AND JULY 5
UVALDE 108 MAY 8 AND JULY 9

JUNE 1ST TO AUGUST 16TH...2009 IS THE DRIEST SUCH PERIOD AT
SAN ANTONIO WITH ONLY 0.97 INCHES OF RAIN...AND THE 10TH DRIEST AT
AUSTIN MABRY WITH 1.62 INCHES OF RAIN. THE SAME PERIOD IS THE 37TH
DRIEST JUNE 1ST TO AUGUST 16TH AT DEL RIO THIS YEAR...WITH 3.24
INCHES OF RAIN. THE TABLE BELOW LISTS THE DRIEST JUNE TO AUGUST
PERIODS FROM THE BEGINNING OF RECORD THROUGH YEAR 2008.

DRIEST JUNE TO AUGUST FROM 1856 TO 2008 AT AUSTIN MABRY

1. 0.92 JUNE TO AUGUST 1910
2. 1.45 JUNE TO AUGUST 1934
3. 1.49 JUNE TO AUGUST 1977
4. 1.50 JUNE TO AUGUST 1884
5. 1.77 JUNE TO AUGUST 1980

DRIEST JUNE TO AUGUST FROM 1871 TO 2008 AT SAN ANTONIO

1. 1.13 JUNE TO AUGUST 1871
2. 1.81 JUNE TO AUGUST 1911
3. 2.00 JUNE TO AUGUST 1938
4. 2.06 JUNE TO AUGUST 1982
5. 2.29 JUNE TO AUGUST 1910

DRIEST JUNE TO AUGUST FROM 1906 TO 2008 AT DEL RIO

1. 0.28 JUNE TO AUGUST 1956
2. 0.48 JUNE TO AUGUST 2001
3. 0.62 JUNE TO AUGUST 1951
4. 0.65 JUNE TO AUGUST 1952
5. 0.75 JUNE TO AUGUST 1989

YEAR TO DATE RAINFALL THROUGH AUGUST 16TH SHOWS JANUARY TO AUGUST
2009 AS ONE THE DRIER JANUARY TO AUGUST PERIODS SO FAR...WITH
ONLY 7.16 INCHES OF RAIN AT DEL RIO...8.02 INCHES OF RAIN AT
SAN ANTONIO...AND 11.48 INCHES OF RAIN AT AUSTIN MABRY. WITH STILL
15 MORE DAYS IN AUGUST THE FIGURES FOR JANUARY TO AUGUST 2009 COULD
CHANGE.

IN THE MEANTIME...THE DRIEST JANUARY TO AUGUST PERIODS THROUGH
YEAR 2008 ARE LISTED BELOW.

AUSTIN MABRY DRIEST JANUARY TO AUGUST PERIODS 1856 TO 2008

1. 7.51 JANUARY TO AUGUST 1925
2. 8.75 JANUARY TO AUGUST 1954
3. 9.59 JANUARY TO AUGUST 1956
4. 10.06 JANUARY TO AUGUST 1984
5. 10.45 JANUARY TO AUGUST 1917
6. 11.91 JANUARY TO AUGUST 1912
7. 12.01 JANUARY TO AUGUST 1879
8. 12.03 JANUARY TO AUGUST 1963
9. 12.10 JANUARY TO AUGUST 1893
10. 12.14 JANUARY TO AUGUST 1875

SAN ANTONIO DRIEST JANUARY TO AUGUST PERIODS 1871 TO 2008

1. 7.16 JANUARY TO AUGUST 1925
2. 7.49 JANUARY TO AUGUST 1917
3. 8.41 JANUARY TO AUGUST 1871
4. 8.98 JANUARY TO AUGUST 1925
5. 9.24 JANUARY TO AUGUST 1910
6. 9.44 JANUARY TO AUGUST 1996
7. 10.23 JANUARY TO AUGUST 1956
8. 10.24 JANUARY TO AUGUST 1953
9. 10.60 JANUARY TO AUGUST 2006
10. 10.69 JANUARY TO AUGUST 1902

DEL RIO DRIEST JANUARY TO AUGUST PERIODS 1906 TO 2008

1. 0.98 JANUARY TO AUGUST 1956
2. 3.10 JANUARY TO AUGUST 1937
3. 3.47 JANUARY TO AUGUST 1933
4. 4.13 JANUARY TO AUGUST 1967
5. 4.33 JANUARY TO AUGUST 1962
6. 4.55 JANUARY TO AUGUST 1951 AND 2001
7. 4.75 JANUARY TO AUGUST 1953
8. 5.69 JANUARY TO AUGUST 1924
9. 5.89 JANUARY TO AUGUST 1989
10. 6.10 JANUARY TO AUGUST 1952

Sunday, August 16, 2009

PM Update: Tropical Storm Ana Depressed, Bill Burgeons, Claudette Continues

11 pm EDT Update: As of 11 pm, Ana was moving across the Leeward Islands with 35 mph winds, Bill had strengthened to just below hurricane force at 70 mph, and Claudette (50 mph) was about to make landfall on the Florida Panhandle from a position about 25 miles west of Panama City.

Original post:
Tropical Storm Ana has continued weakening this afternoon and is now a tropical depression with maximum winds of 35 mph as of 5 pm. Little change in intensity is expected in the next 24 hours, but it could degenerate further into a tropical wave tonight. Tropical Storm Watches are in effect, however, from the Dominican Republic eastward through much of the northeastern Caribbean Islands.

Satellite images show that Tropical Storm Bill has developed an impressive-looking structure, including a central dense overcast, banding, and upper-level outflow. It now has maximum winds of 65 mph. The models continue to forecast strengthening, and one of them has a 38% chance of a 30 kt. increase in wind speed in the next 24 hours. Several of them show Bill becoming a Category 4 hurricane within 5 days.

Tropical Storm Claudette continues approaching a likely landfall on the Florida Panhandle tonight. Winds remain at 50 mph, but some strengthening is still possible. The main threat from this storm is heavy rain, with amounts of 3-6" and isolated maximums of 10" expected. At 4 pm CDT, the storm was centered about 40 miles west-southwest of Apalachicola, Florida moving northwest at 14 mph.

Images (click to enlarge): Forecast tracks for Tropical Storms Bill (upper) and Claudette (middle) and combined 5-day probability of tropical storm force winds from National Hurricane Center

Tropical ABC's: Tropical Storm Claudette Joins Weaker Ana and Stronger Bill

An area of heavy thunderstorm activity in the eastern Gulf of Mexico became Tropical Depression 4 overnight, and it was declared Tropical Storm Claudette at 11:15 CDT based on radar observations. Aircraft reconnaissance subsequently indicated maximum winds have reached 50 mph with higher gusts, and some strengthening is possible before landfall on the northern Gulf Coast of Florida tonight. A Tropical Storm Warning is in effect from the Alabama/Florida border eastward to the Suwanee River in Florida. The storm is centered about 40 miles south of Apalachicola, Florida and is moving northwest at 14 mph.

Meanwhile, Ana has been found to be weakening. Aircraft measurements indicate that the storm is poorly organized, is barely a tropical storm, and could dissipate later today. Maximum winds are 40 mph. As a precaution, a Tropical Storm Watch remains in effect for Puerto Rico, the U.S. and British Virgin Islands, and a number of other islands in the northeastern Caribbean.

Tropical Storm Bill, on the other hand, has strengthened this morning to maximum winds of 60 mph as it moves west-northwest at 16 mph from a position over 1500 miles east of the Lesser Antilles. Favorable environmental conditions in the form of light wind shear and warm water temperatures are expected to contribute to more strengthening, and Bill is forecast to become a hurricane within 24 hours, and a major hurricane in the next several days.

Images (click to enlarge): Forecast tracks for Tropical Storms Claudette (upper) and Bill (lower) from National Hurricane Center

Seasonal Outlook

Latest seasonal forecast: Click here.


Latest 3-month temperature outlook from Climate Prediction Center/NWS/NOAA.