Archive for June, 2009

June 2009: Cloudy, Cool & Wet
June 30, 2009

tt_june_coolandwet

Prelliminary stats are in for June 2009 at BWI-Marshall. The month turned out slightly cooler than normal with only one “sunny” day (cloud cover 30% or less) and no days with a maximum temperature of 90° or higher.

Tom Tasselmyer

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New Weather Satellite Launched
June 29, 2009

NASA has launched the latest weather satellite.

JC_GOES_O_LaunchImage above: Rising above the two lightning towers around the pad, a Delta IV rocket races into the sky with the GOES-O satellite aboard. Photo credit: NASA/Kim Shiflett

The item below is a portion of the press release concerning the launch.

——————————————-

The GOES-O satellite lifted off from Launch Complex 37 at Cape Canaveral Air Force Station in Florida at 6:51 p.m. EDT atop a Delta IV rocket. From a position about 22,300 miles above Earth, the advanced weather satellite will keep an unblinking eye on atmospheric conditions in the Eastern United States and Atlantic Ocean.

Mission Overview
GOES-O is the latest weather satellite developed by NASA to aid the nation’s meteorologists and climate scientists. The acronym stands for Geostationary Operational Environmental Satellite. The spacecraft in the series provide the familiar weather pictures seen on United States television newscasts every day. The satellites are equipped with a formidable array of sensors and instruments.

GOES provides nearly continuous imaging and sounding, which allows forecasters to better measure changes in atmospheric temperature and moisture distributions, hence increasing the accuracy of their forecasts. GOES environmental information is used for a host of applications, including weather monitoring and prediction models.

——————————————————

GOES-O will be parked in a geostationary orbit over the equator and will be tested over the next few weeks. The satellite will then be put in a “storage mode” until it is needed to replace one of the older GOES satellites now in operation.

You can see images and videos about GOES-O by clicking on the following link……..

http://www.nasa.gov/mission_pages/GOES-O/multimedia/index.html

John Collins

Tropics Heating Up
June 27, 2009

A disturbance in the Caribbean is beginning to show signs of organization.

JC_TROPsat

Hurricane forecasters do not see an immediate threat from  the feature but it is expected to drift into the Gulf of Mexico over the next day or two. Conditions will then be more favorable for further development.

If this disturbance were to become the season’s first named storm, the name would be “Ana”.

John Collins

What is a weather forecast worth?
June 26, 2009

A recent survey of American adults found that 96% use weather forecasts to some extent, 87% check the weather forecast at least once per day, and the average value of each forecast for these users is about 10.5 cents.  The survey was conducted in 2006 by the National Center for Atmospheric Research.

Some other interesting revelations from the survey include:

– Americans use about 300 billion weather forecasts each year
– Those surveyed received forecasts 3.8 times per day
– The most common source for weather forecasts is a television station

For more tidbits from this research, see the news release posted below.

Tom Tasselmyer

BOULDER-Close to 9 out of 10 adult Americans obtain weather forecasts regularly, and they do so more than three times each day on average, a new nationwide survey by scientists at the National Center for Atmospheric Research (NCAR) has found. The value Americans place on these forecasts appears to be far more than the nation spends on public and private weather services.

The research is the first comprehensive study of its kind to examine how the public perceives, uses, and values weather forecasts. Funded by the National Science Foundation, NCAR’s sponsor, and the National Oceanic and Atmospheric Administration, the study appears in the June issue of the Bulletin of the American Meteorological Society.

U.S. adults obtain an estimated 300 billion forecasts each year, says NCAR scientist and lead author Jeffrey Lazo. The study also reveals that most people are generally satisfied with weather forecasts and have fairly high confidence in forecasts with a lead time of one to two days.

“Weather forecasts equate to an enormous volume and multiplicity of information,
when you account for the array of forecast providers, communication channels, and the size and diversity of the U.S. population,” Lazo says.

Understanding how individuals use day-to-day weather information can help direct the development of more relevant and valuable weather forecasts and warnings by providers like the National Weather Service, he adds.

Gaining a better understanding of people’s attitudes and behaviors toward forecasts also provides valuable information to forecasters and emergency managers.

“Better communication strategies can be developed for hazardous weather like hurricanes, winter storms, and floods,” Lazo says. “Improved understanding will also help forecasters to communicate forecast uncertainty more effectively.”

—–More than three forecasts a day—–

The Internet-based survey, conducted in November 2006, collected information about respondents’ weather-related activities and experiences, as well as basic demographic information. Of the 1,520 individuals surveyed, 1,465 (96 percent) said they used weather forecasts.

Of those 1,465, 87.1 percent reported getting a forecast at least once a day on average, while 9.2 percent reported doing so once a day or less on average.

Although the number of forecasts a person obtains varies significantly from day to day, depending on factors like weather events and planned activities, the researchers found that on average survey participants received forecasts 3.8 times a day. These findings, when extrapolated to the total U.S. adult population of 226 million, indicate that Americans receive a yearly total of about 300 billion forecasts.

—–Valuing a forecast—–

The authors cautioned that it is difficult to put a dollar figure on the value of forecasts. However, the researchers asked respondents what they believed forecasts to be worth, presenting them with hypothetical amounts that they were currently paying in taxes and asking if they felt that value was correct, worth more, or worth less than the amount indicated.

Respondents indicated that, on a per-household basis, they would place an average value of about 10.5 cents on every forecast obtained. This equates to an annual value of $31.5 billion. In comparison, the cost of providing forecasts by government agencies and private companies is $5.1 billion, according to the paper.

“Our estimates indicate that Americans are getting a good deal on weather forecasts,” says Lazo. “While it’s hard to precisely estimate the value of the forecasts, it is clear that there is a significant difference between the cost of forecasts and the value that people place on them.”

—–Fascination with the weather—–

Coauthor Julie Demuth, an NCAR associate scientist, says the study also reveals people’s curiosity about the weather, with 85 percent of respondents saying that more than half the time they obtain forecasts simply to know what the weather will be like.

“This tells us that people generally have a high level of interest in weather forecasts, regardless of whether they are using this information directly for planning and decision making,” says Demuth.

Many people use forecasts for planning specific activities, such as vacations, and routine daily activities, such as deciding what to wear and how to get to work or school. The peak periods for accessing forecasts are the early morning, early evening, and late evening, says Demuth.

The most common source for forecast information is local television stations, with individuals obtaining forecasts 33.7 times per month on average. Cable television and radio are the next most popular sources. Web pages and newspapers were less common sources overall, but both are a daily or more frequent source of forecasts for 27 percent of respondents.

“We should be doing this type of survey every two to three years so we can see what changes are happening, particularly in how people are using technology like mobile phones and the Internet to receive forecasts,” says Lazo.

The University Corporation for Atmospheric Research manages the National Center for Atmospheric Research under sponsorship by the National Science Foundation. Any opinions, findings and conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

– The End –

Scientific contacts:
Jeffrey Lazo, NCAR Project Lead
303-497-2857
lazo@ucar.edu

Rebecca Morss, NCAR Scientist
303-497-8172
morss@ucar.edu

Julie Demuth, NCAR Associate Scientist
303-497-8112
jdemuth@ucar.edu

Cheryl Dybas, NSF Public Affairs
703-292-7734
cdybas@nsf.gov

Space Station View Of A Volcanic Eruption
June 26, 2009

From Spaceweather.com :

Perfect timing. On June 12th, just as Russia’s Sarychev Peak volcano was erupting for the first time in 20 years, the International Space Station flew directly overhead. Astronauts had their camera ready and snapped one of the most dramatic Earth-science photos ever taken from space:

Researchers are studying this rare photo to learn about the early stages of powerful volcanic eruptions.

To learn more about what the photo reveals, go to:  Spaceweather.com

Tom Tasselmyer

Two More Tornadoes
June 22, 2009

tt_june20_tornadoes

Spring 2009 was cloudy, wet and wild, going out with a round of severe thunderstorms in the final hours of the season. The National Weather Service’s Baltimore/Washington Forecast Office surveyed storm damage in Harford and eastern Baltimore Counties on Sunday and determined two tornadoes did some damage in those areas on Saturday afternoon. The National Weather Service report is posted below.

For those hoping for a change in the cloudy, wet, and stormy weather of spring, keep in mind that the summer solstice occurred at 1:46 a.m. Sunday morning, signaling the official start of a new season…and maybe a new weather pattern.

Tom Tasselmyer

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
318 PM EDT SUN JUN 21 2009

…TWO TORNADOES AND A WATERSPOUT CONFIRMED FROM SATURDAY…

SATURDAY AFTERNOON THREE WEAKER THUNDERSTORMS DEVELOPED QUICKLY
INTO SUPERCELLS WHILE MOVING ACROSS HARFORD…BALTIMORE…AND ANNE
ARUNDEL COUNTY. MUCH OF THE REASON FOR THIS WAS DUE TO THE STORMS
IMPACTING THE BAY BREEZE OVER THESE COUNTIES. THE BAY BREEZE IS
WHERE SLIGHTLY COOLER AIR OFF THE BAY MOVES OVER THE ADJACENT
SHORELINE COMMUNITIES AND SHIFTS THE SURFACE WIND DIRECTION ENOUGH
TO ASSIST WITH TORNADO FORMATION.

THE HARFORD COUNTY STORM PRODUCED A WEAK EF-0 TORNADO…THE
BALTIMORE COUNTY STORM PRODUCED EF-1 DAMAGE AT ITS WORST
POINT…AND THE ANNE ARUNDEL STORM DEVELOPED A WATERSPOUT JUST AS
IT MOVED OVER THE BAY.

HARFORD COUNTY…

AT 3:31 PM A TORNADO TOUCHED DOWN OVER PLEASANT HILLS/STONEYBROOK
MARYLAND. IT KNOCKED DOWN SEVERAL TREES AND LARGE BRANCHES IN THE
COMMUNITY…ONE OF WHICH FELL ON A DELIVERY TRUCK AS IT WAS MAKING
DELIVERIES. THE TORNADO PROCEEDED EAST AND WENT THROUGH SEVERAL QUICK
CYCLES OF DISSIPATION AND REGENERATION AS IT MOVED ALONG
HOLLINGSWORTH DRIVE…CAUSING SPORADIC DAMAGE. THE TORNADO MOVED
ACROSS A FARM BETWEEN HOLLINGSWORTH DRIVE AND RING FACTORY ROAD…
UPROOTING A DOZEN LARGE TREES BEFORE DISSIPATING OVER THE NORTHERN
END OF ATKISSON RESERVOIR AT 3:38 PM.

A NWS SURVEY CONCLUDED THAT THIS STORM WAS CONSISTENT WITH EF-0
DAMAGE. PEAK WINDS WERE ESTIMATED TO BE 75 MPH. THE PATH LENGTH
WAS 3 MILES WITH A WIDTH OF 100 YARDS.

BALTIMORE COUNTY…

AT 3:44 PM A TORNADO TOUCHED DOWN IN ESSEX MARYLAND. IT KNOCKED
DOWN A TREE THAT SEVERELY DAMAGED A HOME. SEVERAL OTHER TREES AND
BRANCHES WERE KNOCKED DOWN AS WELL. STREETS AFFECTED INCLUDED
WOODLYNN RD… LANCE AVE… KINWAT AVE… TIBSEN AVE… AND
HOMBURG AVE. MINOR SHINGLE AND SIDING DAMAGE WAS REPORTED THROUGH
THE COMMUNITY. DAMAGE IN THIS AREA WAS CATEGORIZED AS EF-0 DAMAGE
WITH PEAK WINDS AROUND 70 MPH.

THE STORM CONTINUED SOUTHEAST…MAINLY AS A FUNNEL CLOUD THAT DID
NOT REACH TO THE GROUND… BUT IT DID CAUSE A FEW LARGE BRANCHES
TO GET KNOCKED DOWN SPORADICALLY ALONG THE BACK RIVER NECK RD
CORRIDOR.

THE TORNADO INTENSIFIED AS IT APPROACHED BROWNS CREEK AND
BALLISTON POINT. AT 3:49 THE TORNADO WAS VIDEOTAPED NEARING
BROWNS CREEK. THE STORM MOVED ACROSS THE CREEK AND OVER BALLISTON
POINT AT 3:50 PM. THE TORNADO UPROOTED OR SNAPPED DOWN A
SIGNIFICANT PORTION OF THE LARGE TREES IN THE COMMUNITY ALONG
ISLAND VIEW ROAD…DOZENS IN ALL. THE STORM DISSIPATED AS IT MOVED
OVER THE BAY AT 3:52 PM.

RESIDENTS OF ISLAND VIEW ROAD HAD VIDEO AND PICTURES OF THE
TORNADO AND INDICATED SEEING THE TORNADO WARNING ON TELEVISION
BEFORE THE STORM STRUCK. AN NWS DAMAGE SURVEY REVEALED EF-1 DAMAGE
IN THE BALLISTON POINT AREA WITH PEAK WINDS ESTIMATED TO BE 90
MPH. TOTAL PATH LENGTH FOR THIS TORNADO WAS 5 MILES…ALTHOUGH THE
CIRCULATION SKIPPED AS IT MOVED SOUTHEAST. PATH WIDTH WAS 150
YARDS AT ITS WIDEST.

CHESAPEAKE BAY WATERSPOUT…

LASTLY…A STORM MOVING OVER NORTHERN ANNE ARUNDEL COUNTY MOVED
OUT OVER THE CHESAPEAKE BAY. A WATERSPOUT FORMED AT 3:52 PM AND
MOVED ACROSS THE BAY…PASSING JUST NORTH OF LOVE POINT ON
NORTHERN KENT ISLAND. THE WATERSPOUT DISSIPATED OVER THE CHESTER
RIVER AT 4:10 PM BEFORE IT COULD STRIKE ANY LAND. MOTORISTS ON THE
BAY BRIDGE COULD SEE THE WATERSPOUT AND SEVERAL PICTURES WERE
TAKEN. NO DAMAGE WAS REPORTED FROM THIS EVENT.

$$
STRONG

Stormy Saturday?
June 20, 2009

One more storm complex is slated to move across the region Saturday.

satsfcjThe Saturday morning surface map shows a low pressure area over the Great Lakes with a warm front (stalled at the time of the observations) reaching southeastward over the Bay and a cold front extending southwestward over the Ohio Valley. 

The Mid Atlantic region will be in the warm, humid air mass between these two fronts until the cold front sweeps on to the east overnight.

GOES14452009171Ga2LrKThe morning satellite image shows generally overcast skies over Maryland but there are breaks in the clouds from western Maryland westward. Sunbreaks may develop across the area in the afternoon and the potential additional heating could further destabilize the atmosphere, setting the stage for some strong thunderstorm activity.

day1otlk_1300The National Weather Service Storm Prediction Center has identified the region as having a “Sight Risk” for severe storm activity. The greatest threat would be from damaging straight-line winds and hail. Some tornado development is also possible.

Keep an eye on the sky today.

Sunday is Father’s day … and the first day of summer. The weather should be much improved with only a slight chance for isolated precipitation.

John Collins

Wet, Wet, Wet!!!
June 19, 2009

The area got soaked again Thursday.

  • BWI-Marshall Airport … 1.77″
  • Baltimore Inner Harbor … .96″
  • TV-Hill … .73″

This continues the trend we have seen all spring with considerable cloud cover and excessive rainfall.

JC_HighOnPrecip

More rain is in the forecast for the final couple of days of spring. The forecast map below shows the next storm system that will be moving into the area. Rain chances are fairly high for Friday night and Saturday.

JC_FriEvSfc

Summer officially starts Sunday at 1:46am. It is Father’s Day and it looks like rain chances will be decreasing.

John Collins

Missing Sunshine
June 16, 2009

tt_wheres_the_sun

With another cloud day recorded on Tuesday, there have been no “sunny” days in Baltimore this June.  A sunny day, climatologically, is a day when the sunrise to sunset cloud cover is 30% or less.  In fact, for April, May, and the first half of June, there have been just 10 “sunny” days.  The normal number of sunny days from April through June is 24.

Tom Tasselmyer

Dundalk Tornado
June 12, 2009

Dundalk Tornado 9June09

A report from the National Weather Service has confirmed the stormy nature of this second week of June 2009 in the Baltimore area.  The Storm Damage Survey Team from the Baltimore/Washington Forecast Office was able to determine that a small tornado briefly touched down in the Dundalk area Tuesday afternoon.  Details of their report are posted below.  Ben Petre notified us that he thinks he caught the tornado on his cell phone camera so I have posted that image here as well.

Tom Tasselmyer

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
747 PM EDT WED JUN 10 2009

…EF-0 TORNADO CONFIRMED IN DUNDALK MARYLAND ON TUE JUNE 9TH…

TODAY THE BALTIMORE/WASHINGTON WEATHER FORECAST OFFICE OF THE NATIONAL WEATHER SERVICE CONDUCTED A SURVEY OF STORM DAMAGE THAT OCCURRED ON JUNE 9TH IN DUNDALK MARYLAND IN BALTIMORE COUNTY. THE SURVEY WAS CONDUCTED IN CONCERT WITH BALTIMORE COUNTY OFFICE OF HOMELAND SECURITY AND EMERGENCY MANAGEMENT.

THE FOLLOWING WAS DETERMINED THROUGH A DAMAGE SURVEY…EXAMINATION OF RADAR AND EYEWITNESS INTERVIEWS.

BASED ON ALL EVIDENCE THE DAMAGE WAS CONSISTENT WITH A BRIEF SMALL TORNADO RATED EF-0 ON THE ENHANCED FUJITA SCALE…WITH PEAK WINDS ESTIMATED AT 70 MPH. PATH LENGTH WAS ONE MILE…WITH A MAX WIDTH OF 150 YARDS. INITIAL TIME OF TOUCHDOWN WAS 5:21 PM EDT…AND WAS ON THE GROUND FOR ABOUT ONE MINUTE.

NO INJURIES WERE REPORTED.

NO DAMAGE COST ESTIMATE WAS AVAILABLE AT THIS TIME.

EVIDENCE OF THE TORNADO WAS FIRST NOTED ALONG THE NORTHERN EDGE OF OAK LAWN CEMETERY AND THE ADJOINING EASTPOINT NEIGHBORHOOD NORTH OF THE CEMETERY…DUE MAINLY TO TREES SNAPPED OR UPROOTED. MORE DAMAGE WAS NOTED ALONG BREAD AND CHEESE CREEK FROM CARSON AVENUE EAST TO PLAINFIELD RD. THE TORNADO PRODUCED STRUCTURE DAMAGE TO 3 TOWNHOUSES ON BERKSHIRE LANE…WHERE PORTIONS OF THEIR FLAT TAR-PITCH ROOF WERE REMOVED…A TREE FELL ON ANOTHER TOWNHOUSE ON BERKSHIRE…AND A NEARBY CAR DEALERSHIP LOST A PORTION OF ITS CANVASS ROOF COVERING. THE MOST CONCENTRATED DAMAGE WAS OBSERVED FROM THE BERKSHIRE RD AREA…ACROSS MERRITT BLVD TO PLAINFIELD RD…WHERE MULTIPLE TREES WERE SNAPPED AND/OR UP-ROOTED…WITH ONE TREE FALLING ON A HOUSE.

THE TORNADO APPEARED TO WEAKEN QUICKLY AS IT MOVED FURTHER EAST THROUGH THE GRAY MANOR NEIGHBORHOOD…AND NO DAMAGE WAS OBSERVED EAST OF WOODWELL RD.

EYEWITNESS ACCOUNTS AND EXAMINATION OF RADAR DATA SUGGEST THE TORNADO BEGAN AS A GUSTNADO…A SPIN-UP CIRCULATION THAT FORMS ON THE LEADING EDGE OF A THUNDERSTORM GUST FRONT. IT QUICKLY TRANSFORMED INTO A MORE TRADITIONAL TORNADO…DEVELOPING AS A NEW THUNDERSTORM UPDRAFT OVERRAN THE ORIGINAL GUST FRONT AND BECAME COLLOCATED OVER THE ORIGINAL GUSTNADO. EYEWITNESSES REPORTED SEEING DEBRIS…TREE LIMBS AND ROOFING MATERIAL…BEING LIFTED UPWARDS INTO THE TORNADO CIRCULATION. ONE EYEWITNESS ON PLAINFIELD RD DESCRIBED THE SOUND OF A FREIGHT TRAIN AS THE TORNADO PASSED OVER HIS HOUSE.

THE WEATHER SERVICE EXTENDS THANKS TO BALTIMORE COUNTY EMERGENCY MANAGEMENT OFFICIALS…AND TO SOME MEMBERS OF LOCAL MEDIA WHO ASSISTED IN POINTING OUT LOCATIONS OF DAMAGE IN DUNDALK.

$$
STEVE ZUBRICK
SCIENCE AND OPERATIONS OFFICER
NATIONAL WEATHER SERVICE
BALTIMORE/WASHINGTON FORECAST OFFICE
STERLING VIRGINIA