Archive for September, 2010

Wet, Wet, Wet!!!
September 30, 2010

A quick look at some rain totals through mid afternoon……

3.61″   BWI (old record 1.6″ 1920)

3.21″   Inner Harbor

2.89″   TV Hill

7.55″   Annapolis

6.66″   Pasadena

5.62″   Edgewater

6.35″   Port Deposit

4.40″   Rock Hall

8.50″   Patuxent River NAS

The map below outlines the mid afternoon Doppler Radar estimate of the most significant rains in the area.

A second impulse of rain is moving up from the south and could approach the rain totals achieved to this point.

John Collins

Nicole Dissipates…Heavy Rain Still Moving North
September 30, 2010

Tropical Storm Nicole lasted for just a few hours; declared the 14th named storm of the season with the 11:00 a.m. advisory from the National Hurricane Center, the storm had dissipated as of 5:00 p.m.

TROPICAL STORM NICOLE DISCUSSION NUMBER   6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL162010
500 PM EDT WED SEP 29 2010

SATELLITE...AIRCRAFT...AND SURFACE DATA SHOW THAT THE CIRCULATION OF
NICOLE HAS BECOME ELONGATED THIS AFTERNOON.  THE CENTER...
WHICH WAS NEVER VERY WELL DEFINED...HAS BECOME UN-TRACKABLE AND
THIS WILL BE THE LAST NHC ADVISORY ON THIS SYSTEM.





However, while the center of the tropical low pressure system became “un-trackable” earlier this afternoon, the abundant moisture associated with this system is still evident on satellite and radar imagery this evening.  Computer models continue to show a series of low pressure systems moving north along the south Atlantic coast toward Maryland tonight and Thursday.  These low pressure systems, and the tropical moisture tied up in them, will bring a threat of heavy rain and severe thunderstorms to Maryland Thursday.  As of late Wednesday evening the main threats to Maryland on Thursday are:

Rainfall:  2-5″, possibly more than 5″ on the eastern shore

Winds:  Gusts to 35 mph in heavier showers

Severe Storms:  Isolated severe thunderstorms with possible tornadoes

Tides:  Tides on the western shore of the bay 1 to 2 feet above normal

Tom Tasselmyer

Tropical Soaking On The Way
September 29, 2010

UPDATE … 2pm Wednesday …….Tropical Depression 16 has been upgraded to a marginal tropical storm (Nicole) with 40 mph winds circulating around an ill defined center between Cuba and Florida. The latest computer model analysis indicates that the storm may take a more easterly track than previously thought. This raises the level of uncertainty of the storm’s impact on the Mid Atlantic region over the next 24 to 48 hours. Check back for updates later today.

+++++++++

Tropical Depression 16 continues it’s northward track. While the storm may reach marginal tropical storm strength, it appears the storm’s major impact will likely be excessive rainfall.

The overnight water vapor satellite image below from the Naval Research Laboratory shows wind circulation at the middle and high levels of the atmosphere.

Upper level winds circulating around low pressure areas over the Atlantic Ocean and the U.S. Mainland are channeling tropical moisture up the eastern seaboard. This same circulation pattern will draw the tropical depression up the coast as well.

The end result can be seen on the National Hurricane Center’s forecast track map for the storm. The storm is expected top be “post-tropical” in nature by the time it reaches the Mid Atlantic Region.

The map above shows what the situation will be Thursday morning.

The map below shows estimates for rainfall through Friday morning.

You can click on any of the maps and pictures to enlarge them.

The bottom line is that Thursday will be stormy with rainfall in the 2-4 inch range. Some flooding is likely. Winds will be gusty and may contribute to high tides on the Bay running as much as three feet above normal. Some severe thunderstorm activity is possible.

Keep checking wbaltv.com and all of WBAL-TV’s newscasts for updates.

Stay dry.

John Collins

TD 16 (Nicole?) Headed This Way?
September 28, 2010

The 5:00pm update from the National Hurricane Center (NHC) indicated Tropical Depression #16 has not yet reached tropical storm strength.  Maximum sustained winds are still around 35 mph and the satellite imagery indicates the storm is still disorganized.  In fact, to quote the NHC, “clearly, this is not a classical tropical cyclone”.  Still, the forecast is for some strengthening and TD #16 is expected to become Tropical Storm Nicole over the next 24 hours.

The forecast track takes the low pressure system north toward Miami and eventually near Wilmington, NC Thursday afternoon.  From there computer models bring the tropical moisture north into Virginia and Maryland with the potential for 3-5″ of rain along the path of the storm.  If the forecast verifies, Thursday could be very soggy around here with the possibility of severe thunderstorms and tornadoes in parts of central and eastern Maryland.  Stay tuned to this blog for updates and check out our hurricane section.

Tom Tasselmyer

Wet And Getting Wetter
September 28, 2010

Some areas across the region got a good soaking on Monday.

The map above show rain total for Monday from various reports received by the National Weather Service.

The pattern really doesn’t change that much over the next several days as tropical moisture will continue to be channeled northward from the Caribbean and Gulf of Mexico.

A new twist is the development of Tropical Depression 16 in the western Caribbean. If strengthening continues as expected the storm will become Nicole.

The storm is forecast to reach marginal tropical storm strength and track across western Cuba and southeast Florida and then losing any well defined identity as it approaches the South Carolina coast. The remnant of the storm is expected to continue northward and carry a significant plume of tropical moisture to the Chesapeake Bay region.

The forecast map above shows the rain total outlook along the eastern seaboard through Friday morning. The heaviest rains locally will be most likely fall Wednesday night and Thursday.

Don’t put your umbrella away.

John Collins

Matthew is the 13th Tropical Storm of 2010
September 24, 2010

Just prior to the beginning of the 2010 hurricane season the National Weather Service’s Climate Prediction Center forecast an “active to extremely active” season in the Atlantic Basin.  The forecast was for a 70% chance of 14 to 23 named storms.  Today the 13th named storm of the season, Matthew, formed in the Caribbean.  With more than two months left in the season (June 1st through November 30th), just one more named storm will verify the forecast.  So far this year there have been six hurricanes in the Atlantic Basin, the forecast made at the end of May was for 8 to 14 tropical storms reaching hurricane strength.

Matthew is a weak tropical storm as of Thursday evening, but it is forecast to become a category 1 hurricane as it moves toward central America and the Yucatan Peninsula of Mexico.

Tom Tasselmyer

10th Twister In New York City Since 1950
September 18, 2010

National Weather Service meteorologists investigating damage from thunderstorms that swept through Brooklyn and Queens in New York City on Thursday have confirmed two tornadoes touched down.  The tornado in Brooklyn was rated EF-0 with maximum wind speeds of 80 mph.  The Queens tornado was slightly stronger, rated EF-1 with maximum winds of 100 mph.  Interestingly, straight line winds not associated with a tornado, but with a macroburst, produced with highest wind gusts which were estimated at 125 mph.  The two tornadoes were the 9th and 10th confirmed in New York City since 1950 and the third this summer.  A weak tornado touched down in the Bronx back in July.  The complete report from the National Weather Service is posted below:

PUBLIC INFORMATION STATEMENT...
NATIONAL WEATHER SERVICE NEW YORK NY
1022 PM EDT FRI SEP 17 2010

...TWO TORNADOES AND A MACROBURST CONFIRMED ON SEPTEMBER 16 2010...  

...TORNADO CONFIRMED NEAR PARK SLOPE IN KINGS COUNTY (BROOKLYN) NY...

LOCATION...PARK SLOPE IN KINGS COUNTY (BROOKLYN) NY
DATE...SEPTEMBER 16 2010
ESTIMATED TIME...5:33 PM EDT
MAXIMUM EF-SCALE RATING...EF0
ESTIMATED MAXIMUM WIND SPEED...80 MPH
MAXIMUM PATH WIDTH...75 YARDS
YARDS PATH LENGTH...2 MILES
BEGINNING LAT/LON...40.67 N / 73.99 W
ENDING LAT/LON...40.69 N /73.96 W
* FATALITIES...0
* INJURIES...0

* THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENT(S) AND PUBLICATION IN NWS
STORM DATA.

...SUMMARY...
THE NATIONAL WEATHER SERVICE IN NEW YORK NY HAS CONFIRMED A TORNADO
NEAR PARK SLOPE (BROOKLYN) IN KINGS COUNTY NY ON SEPTEMBER 16 2010.

THE TORNADO TOUCHED DOWN IN PARK SLOPE AND LIFTED 2 MILES NE OF
PARK SLOPE.

THIS INFORMATION CAN ALSO BE FOUND ON OUR WEBSITE AT
WEATHER.GOV/NYC.

FOR REFERENCE...THE ENHANCED FUJITA SCALE CLASSIFIES TORNADOES INTO
THE FOLLOWING CATEGORIES:

EF0...WIND SPEEDS 65 TO 85 MPH.
EF1...WIND SPEEDS 86 TO 110 MPH.
EF2...WIND SPEEDS 111 TO 135 MPH.
EF3...WIND SPEEDS 136 TO 165 MPH.
EF4...WIND SPEEDS 166 TO 200 MPH.
EF5...WIND SPEEDS GREATER THAN 200 MPH.

&&

...TORNADO CONFIRMED NEAR FLUSHING AND BAYSIDE IN QUEENS COUNTY NY...

LOCATION...FLUSHING/BAYSIDE IN QUEENS COUNTY NY
DATE...SEPTEMBER 16 2010
ESTIMATED TIME...5:42 PM EDT
MAXIMUM EF-SCALE RATING...EF1
ESTIMATED MAXIMUM WIND SPEED...100 MPH
MAXIMUM PATH WIDTH...100 YARDS
PATH LENGTH...4 MILES
BEGINNING LAT/LON...40.74 N / 73.84 W
ENDING LAT/LON...40.80 N / 73.76 W
* FATALITIES...1
* INJURIES...0

* THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENT(S) AND PUBLICATION IN NWS
STORM DATA.

...SUMMARY...
THE NATIONAL WEATHER SERVICE IN NEW YORK NY HAS CONFIRMED A TORNADO
NEAR FLUSHING/BAYSIDE IN QUEENS COUNTY NY ON SEPTEMBER 16 2010.

THE TORNADO TOUCHED DOWN 2 1/2 MILES SOUTH OF FLUSHING AND LIFTED
1 MILE NE OF BAYSIDE.

THIS INFORMATION CAN ALSO BE FOUND ON OUR WEBSITE AT
WEATHER.GOV/NYC.

FOR REFERENCE...THE ENHANCED FUJITA SCALE CLASSIFIES TORNADOES INTO
THE FOLLOWING CATEGORIES:

EF0...WIND SPEEDS 65 TO 85 MPH.
EF1...WIND SPEEDS 86 TO 110 MPH.
EF2...WIND SPEEDS 111 TO 135 MPH.
EF3...WIND SPEEDS 136 TO 165 MPH.
EF4...WIND SPEEDS 166 TO 200 MPH.
EF5...WIND SPEEDS GREATER THAN 200 MPH.

&&

...MACROBURST /STRAIGHT LINE WIND DAMAGE/ CONFIRMED NEAR
MIDDLE VILLAGE AND FOREST HILLS IN QUEENS COUNTY NY...

LOCATION...MIDDLE VILLAGE/FOREST HILLS IN QUEENS COUNTY NY
DATE...SEPTEMBER 16 2010
ESTIMATED TIME...5:40 PM EDT
ESTIMATED MAXIMUM WIND SPEED...125 MPH
MAXIMUM PATH WIDTH...5 MILES
PATH LENGTH...8 MILES
* FATALITIES...0
* INJURIES...0

* THE INFORMATION IN THIS STATEMENT IS PRELIMINARY AND SUBJECT TO
CHANGE PENDING FINAL REVIEW OF THE EVENT(S) AND PUBLICATION IN NWS
STORM DATA.

...SUMMARY...
THE NATIONAL WEATHER SERVICE IN NEW YORK NY HAS CONFIRMED A
MACROBURST /STRAIGHT LINE WIND DAMAGE/ NEAR MIDDLE VILLAGE IN QUEENS
COUNTY NY ON SEPTEMBER 16 2010.

THE PATH OF THE MACROBURST WAS FROM MIDDLE VILLAGE TO FOREST HILLS.

THIS INFORMATION CAN ALSO BE FOUND ON OUR WEBSITE AT
WEATHER.GOV/NYC.

FOR REFERENCE...
A MACROBURST IS A CONVECTIVE DOWNDRAFT WITH AN AFFECTED OUTFLOW AREA
OF AT LEAST 2 1/2 MILES WIDE AND PEAK WINDS LASTING BETWEEN 5 AND 20
MINUTES. INTENSE MACROBURSTS MAY CAUSE TORNADO-FORCE DAMAGE OF UP TO
EF3 INTENSITY. STRAIGHT-LINE WINDS ARE GENERALLY ANY WIND THAT IS
NOT ASSOCIATED WITH ROTATION...USED MAINLY TO DIFFERENTIATE THEM
FROM TORNADIC WINDS.

Tom Tasselmyer

Get A Look At Igor
September 17, 2010

Take a look at Hurricane Igor this weekend from the perspective of the Bermuda Weather Service. For example, there is a live radar loop that will show the eye of the storm nicely and a live webcam that should be interesting. Check these out:

webcam from Bermuda: http://www.weather.bm/webcam.asp

radar from Bermuda: http://www.weather.bm/radarLarge.asp

more radar: http://www.weather.bm/radar.asp

Bermuda Weather Service main page: http://www.weather.bm/index.asp

You can also track the tropics on our website at http://www.wbaltv.com/hurricanetracker
Or, try our interactive radar to track the storms at http://www.wbaltv.com/interactive-radar

-Tom

Igor Visits NOAA Buoy 41044
September 17, 2010

A valuable sample of meteorological data was gathered Thursday evening as the center of hurricane Igor passed close to one of the National Oceanic and Atmospheric Administration’s buoys maintained by the National Data Buoy Center.  The buoy, similar to the one pictured above, is moored in 17,600 feet of water located at latitude 21.652 N and longitude 58.695 W, which is a few hundred miles northeast of Puerto Rico.

The chart above shows the wind speed and air pressure as Igor passed by the buoy.  The barometric pressure trace (green) plummets to its lowest point, 27.8″ just after 00 GMT (8pm EDT) as the peak wind gust (red) reaches 85 knots (98 mph).  Shortly thereafter the wind gusts subside and the pressure begins to sharply rise.  The buoy also reported 38 foot waves and a water temperature of 83F.

Igor has weakened somewhat but remains a very dangerous category 3 hurricane with maximum sustained winds of 125 mph near the eyewall, hurricane force (74 mph) winds extending out 105 miles from the center, and tropical storm force winds (40 mph) reaching out 290 miles from the center.

With the storm still forecast to move in the direction of Bermuda, perhaps passing over or very near the island Sunday evening, the probability of hurricane force winds impacting Bermuda has increased to 30%  with a slightly over 50% probability of storm force (58 mph) winds reaching the island.  A Hurricane Watch has been issued for Bermuda.  Large swells and dangerous rip currents are expected to reach the beaches along the mid Atlantic coast of the United States on Friday and last through the weekend.

Tom Tasselmyer

Hurricane Triple Play
September 16, 2010

The National Hurricane Center is currently tracking three hurricanes; two in the Atlantic and one in the far southern Gulf of Mexico.  Karl in the southern Gulf of Mexico is a category 1 storm with maximum sustained winds of 75 mph.  Julia is a category 2 storm with 100 mph winds.

BULLETIN
HURRICANE IGOR ADVISORY NUMBER  34
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL     AL112010
1100 AM AST THU SEP 16 2010 

...LARGE AND POWERFUL IGOR MOVING SLOWLY NORTHWESTWARD...

SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...21.0N 57.2W
ABOUT 430 MI...ENE OF THE NORTHERN LEEWARD ISLANDS
ABOUT 910 MI...SSE OF BERMUDA
MAXIMUM SUSTAINED WINDS...140 MPH...
PRESENT MOVEMENT...NW OR 305 DEGREES AT 7 MPH...
MINIMUM CENTRAL PRESSURE...934 MB...27.58 INCHES

Igor remains the most powerful of the three, it is a category 4 storm with maximum sustained winds estimated around 140 mph.  A recon plane will investigate the storm this morning and send back a more accurate assessment of the storm’s strength.

The forecast track of Igor continues to pose a threat to Bermuda this weekend with the center of the storm possibly passing just east of the island Sunday evening.  The probability of hurricane force winds (74 mph) reaching the island is currently around 20%, but the probability of storm force winds (58 mph) rises to 40%.

Tom Tasselmyer