Friday, May 29, 2009

DC Region Rain Reign Remains

Image (click to enlarge): Monthly precipitation percentage of average as of 8 am May 29 from National Weather Service

May 31 correction: May 2009 is the 6th wettest in Washington.

6:30 pm Update: The additional 0.32" at Washington National since 5:00 puts this May past 1989 into 6th place.

6 pm Update: Additional amounts in the past hour:
Washington National 0.06"
Washington Dulles 0.36"
Baltimore (BWI) Trace
Original post:
Continuing thundershowers this afternoon have added to the already soggy May rainfall totals in the Washington, DC region. Month-to-date totals through 8 am this morning were already above 150% of average for the District of Columbia and much of adjacent Maryland and Virginia. Amounts have been particularly high in southern Montgomery County, MD and northern Fairfax County, VA, where some places (dark blue on the map) reached 200-300% of average before today's additional downpours.

As of 5 pm, daily and monthly totals were:
Washington National 0.43"/7.47"
Washington Dulles 0.40"/9.90"
Baltimore (BWI) 0.89"/8.00"
The total at National now makes this May in the 7th wettest in Washington history.

Here are some rainfall amounts from Thursday's storms reported by the National Weather Service:
********************STORM TOTAL RAINFALL********************  

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

MARYLAND

..MONTGOMERY COUNTY

BARNESVILLE 1.42 615 PM 5/28 LOCAL MESONET
DAMASCUS 1.01 615 PM 5/28 LOCAL MESONET
MONTGOMERY CTY 0.74 555 PM 5/28 AWOS-METAR

VIRGINIA

..AUGUSTA COUNTY

CHAPIN 2W 1.50 613 PM 5/28 IFLOWS-ELLIOTS KNOB

..FAIRFAX COUNTY

WASH DC/DULLES ARPT 1.00 452 PM 5/28 METAR
HERNDON 0.79 530 PM 5/28 LOCAL MESONET

..FREDERICK COUNTY

GAINESBORO 1.88 500 PM 5/28 LOCAL MESONET

..LOUDOUN COUNTY

STERLING 0.75 600 PM 5/28 LOCAL MESONET

WEST VIRGINIA

..HAMPSHIRE COUNTY

CAPON BRIDGE 1.14 330 PM 5/28 LOCAL MESONET

Copenhagen Climate Change Conclusions

Just back from this week's World Business Summit on Climate Change in Copenhagen, CNBC's political correspondent John Harwood reported this morning on the "key takeaways" regarding an emerging global consensus on climate:
  • Is it a threat? Yes
  • Can markets fix it? No
  • Will governments act? Yes





At the conference, world business leaders issued a call for a climate treaty that creates
clear long-term certainty on incentives, targets and time lines for unleashing the private sector strategies and investments needed to make a low-carbon economy possible.
The full text of the conference's statement calls for:
  1. Agreement on a science-based greenhouse gas stabilization path with 2020 and 2050 emissions reduction targets that will achieve it;
  2. Effective measurement, reporting and verification of emissions performance by business;
  3. Incentives for a dramatic increase in financing low emissions technologies;
  4. Deployment of existing low-emissions technologies and the development of new ones;
  5. Funds to make communities more resilient and able to adapt to the effects of climate change, and
  6. Means to finance forest protection.


Wednesday, May 27, 2009

More Daily Rainfall Records

The National Climatic Data Center reports the following daily rainfall records for May 26:
                                PREV
DATE REC PREV YEAR POR ST NAME
---------- ---- ---- ---- --- -- --------------------------
Virginia
5/26/2009 2.87 0.67 1997 31 VA STERLING RCS
5/26/2009 2.76 1.31 1997 94 VA MT WEATHER
5/26/2009 2.15 1.62 1952 57 VA WOOLWINE 4 S
5/26/2009 1.56 1.11 1945 116 VA DALE ENTERPRISE
5/26/2009 1.44 1.07 1987 58 VA MEADOWS OF DAN 5 SW
5/26/2009 1.3 0.96 1965 45 VA CRAIGSVILLE 2 S
5/26/2009 1.11 0.88 1977 41 VA GLASGOW 1 SE
5/26/2009 0.98 0.89 2001 48 VA COVINGTON FLTR PLT
5/26/2009 0.69 0.14 2006 46 VA CHARLOTTESVILLE FAA AP
5/26/2009 0.63 0.3 1909 102 VA GALAX WTP

West Virginia
5/26/2009 1.56 1.1 1998 45 WV WAYNE 2
5/26/2009 1.48 0.7 2001 56 WV BUCKEYE
5/26/2009 1.3 0.73 1997 34 WV SNOWSHOE
5/26/2009 1.23 1.2 1997 67 WV IAEGER 1 SW
5/26/2009 0.86 0.76 1998 47 WV DRY CREEK

North Carolina
5/26/2009 3.32 2.05 1948 96 NC ELKIN
5/26/2009 3.1 1.19 2004 43 NC W KERR SCOTT RSVR
5/26/2009 2.7 2.23 1946 73 NC ROSMAN
5/26/2009 2.42 1.5 1906 107 NC BREVARD
5/26/2009 2.17 1.97 1938 76 NC WILMINGTON INTL AP (KILM)
5/26/2009 1.95 0.91 1975 60 NC BENT CREEK
5/26/2009 1.1 0.6 1907 116 NC MT HOLLY 4 NE
5/26/2009 0.78 0.77 1959 53 NC CASAR


POR: Period of record in years

Tuesday, May 26, 2009

More on Cap & Trade (Waxman-Markey Bill)

Record Mid Atlantic Rainfall for May 26

Images (click to enlarge): 24-hour precipitation ending at 8 am, May 26, from National Weather Service/NOAA; Washington, DC 2008-9 monthly precipitation vs. average, CapitalClimate chart from NWS data

May 27 Update: Even with 4 more days providing several more opportunities for adding to the month's total, it's going to be hard for this May to reach the 10.66" recorded just last year at Washington National, which made it the 3rd wettest in Washington history. Nevertheless, May 2009 is already the 10th wettest May, and it's well within striking distance of the 8th or even 7th spot. Here are the current top 9:
1889 10.69
1953 10.69"
2008 10.66"
1886 10.60"
1948 8.87"
1989 7.77"
2003 7.06"
1946 6.99"
1897 6.97

Evening Update: More National Weather Service reports:
A RECORD RAINFALL OF 3.59 INCH(ES) WAS SET AT WASHINGTON DULLES DC TODAY.   
THIS BREAKS THE OLD RECORD OF 1.59 SET IN 2002.

**********************12 HOUR RAINFALL**********************

LOCATION 12 HOUR TIME/DATE COMMENTS
RAINFALL OF
(INCHES) MEASUREMENT

DISTRICT OF COLUMBIA

..DISTRICT OF COLUMBIA

WASHINGTON 3.63 1214 PM 5/26 LOCAL MESONET

MARYLAND

..PRINCE GEORGE'S COUNTY

GREENBELT 2.50 809 AM 5/26

VIRGINIA

..FAIRFAX COUNTY

HERNDON 3.03 929 AM 5/26 LOCAL MESONET
CHANTILLY 2.97 914 AM 5/26 LOCAL MESONET

..LOUDOUN COUNTY

STERLING 3.03 1129 AM 5/26 LOCAL MESONET
ASHBURN 2.50 1128 AM 5/26 LOCAL MESONET

**********************24 HOUR RAINFALL**********************

LOCATION 24 HOUR TIME/DATE COMMENTS
RAINFALL OF
(INCHES) MEASUREMENT

DISTRICT OF COLUMBIA

..DISTRICT OF COLUMBIA

NATIONAL ARBORETUM 2.55 824 AM 5/26 COOP
DALECARLIA RESERVIOR 2.02 800 AM 5/26 COOP
WASHINGTON 5.0 N 1.30 700 AM 5/26 COCORAHS

MARYLAND

..ANNE ARUNDEL COUNTY

LAUREL 2.7 E 4.01 800 AM 5/26 COCORAHS
SEVERN 2.0 W 3.35 700 AM 5/26 COCORAHS
BALTO/WASH INTL 2.58 800 AM 5/26 METAR
ODENTON 0.8 WSW 2.07 700 AM 5/26 COCORAHS

..CHARLES COUNTY

WALDORF 3.2 SW 2.69 700 AM 5/26 COCORAHS

..CITY OF BALTIMORE

BALTIMORE - CYLBUR 1.45 800 AM 5/26 COOP

..HOWARD COUNTY

CLARKSVILLE 3.40 800 AM 5/26 COCORAHS 1.0SE
LAUREL 2.90 1200 PM 5/26
COLUMBIA 1.7 W 2.83 600 AM 5/26 COCORAHS
NORTH LAUREL 1.5 ESE 2.65 700 AM 5/26 COCORAHS

..MONTGOMERY COUNTY

SILVER SPRING 0.9 N 4.10 700 AM 5/26 COCORAHS
TAKOMA PARK 0.6 NNW 3.71 700 AM 5/26 COCORAHS
WHITE OAK 1.2 N 3.40 700 AM 5/26 COCORAHS
WHEATON-GLENMONT 0.7 2.71 700 AM 5/26 COCORAHS
OLNEY 0.4 ESE 2.34 700 AM 5/26 COCORAHS

..PRINCE GEORGE'S COUNTY

GREENBELT 4.00 809 AM 5/26
LAUREL 3.49 800 AM 5/26 COCORAHS 2.0S

VIRGINIA

..ALBEMARLE COUNTY

RUCKERSVILLE 1.30 812 AM 5/26

..ARLINGTON COUNTY

ARLINGTON 1.1 NW 1.75 715 AM 5/26 COCORAHS
REAGAN NATIONAL 1.47 800 AM 5/26 METAR

..CITY OF ALEXANDRIA

ALEXANDRIA 1.8 S 1.99 740 AM 5/26 COCORAHS 1.8S

..CLARKE COUNTY

MOUNT WEATHER 2.76 700 AM 5/26 COOP

..FAIRFAX COUNTY

WASH DC/DULLES 3.63 800 AM 5/26 METAR
FRANCONIA 1.3 SSE 1.45 730 AM 5/26 COCORAHS

..FREDERICK COUNTY

STEPHENS CITY 2.2 E 1.61 700 AM 5/26 COCORAHS

..GREENE COUNTY

STANARDSVILLE 2.1 1.59 600 AM 5/26 COCORAHS

..LOUDOUN COUNTY

STERLING PARK 4.00 839 AM 5/26
STERLING NWS/WFO 2.87 700 AM 5/26 WFO STERLING
STERLING 2.15 700 AM 5/26 COCORAHS 3.7NNW
ROUND HILL 2.7 WSW 1.62 700 AM 5/26 COCORAHS

..PAGE COUNTY

LURAY 1.60 900 AM 5/26 COOP

..PRINCE WILLIAM COUNTY

LAKE RIDGE 1.7 SW 2.22 700 AM 5/26 COCORAHS 1.7SW

..ROCKINGHAM COUNTY

DALE ENTERPRISE 1.56 700 AM 5/26 COOP

PM Update: Daily totals through 5 pm as reported by NWS show National at 1.65". The totals for Dulles and BWI are as previously shown, and all 3 are daily records. Month-to-date/year-to-date totals are:
Washington National 6.95"/16.17"
Washington Dulles 8.35"/17.86"
Baltimore (BWI) 7.09"/17.95"
These are all at least 100% above average, but still below the monthly records for May. Notice the high percentage of the 5-month total accounted for by May alone.

Original post:
Heavy downpours overnight and into this morning have caused some local flash flooding in the Washington, DC region. Through mid afternoon, daily total rainfall amounts have already exceeded the record for May 26 at all 3 major reporting locations:
Washington National 1.66"
Washington Dulles 3.59"
Baltimore (BWI) 2.28"
The reading at Dulles is more than double the previous record for May 26, 1.59" in 2002. It's also close to the all-time daily record for May, 3.73" on May 11, 2008. The BWI amount is also a daily record, exceeding the 1.72" on May 26, 2001. At Washington National, the total is just slightly higher than the previous record of 1.49" in 2001.

The following rainfall amounts were reported by the National Weather Service as of 8 am this morning:
***********************6 HOUR RAINFALL***********************

LOCATION 6 HOUR TIME/DATE COMMENTS
RAINFALL OF
(INCHES) MEASUREMENT


VIRGINIA

...LOUDOUN COUNTY...
DULLES AIRPORT DAM 3.63 811 AM 5/26
STERLING NWS/WFO 2.79 812 AM 5/26

**********************12 HOUR RAINFALL**********************

LOCATION 12 HOUR TIME/DATE COMMENTS
RAINFALL OF
(INCHES) MEASUREMENT


MARYLAND

...PRINCE GEORGE`S COUNTY...
GREENBELT 2.50 809 AM 5/26

**********************24 HOUR RAINFALL**********************

LOCATION 24 HOUR TIME/DATE COMMENTS
RAINFALL OF
(INCHES) MEASUREMENT


MARYLAND

...PRINCE GEORGE`S COUNTY...
GREENBELT 4.00 809 AM 5/26

Seasonal Outlook

Latest seasonal forecast: Click here.


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