| |
W1GMF > SKYWRN 04.05.06 11:46l 172 Lines 9522 Bytes #999 (0) @ NEBBS
BID : 44434_W1GMF
Read: GUEST
Subj: SKYWARN WEATHER PREP WEEK
Path: ON0AR<ON0AR<HS1LMV<7M3TJZ<CX2SA<HP2AT<KD4GCA<N1UAN<N1UAN<W1GMF
Sent: 060504/1131Z @:W1GMF.#EMA.MA.USA.NOAM #:44434 [Abington, MA FN42MC]
From: W1GMF@W1GMF.#EMA.MA.USA.NOAM
To : SKYWRN@NEBBS
Hello to all….
This week is Severe Weather Preparedness Week in Southern New England. The National Weather Service in Taunton Massachusetts is issuing Public Information Statements on the characertistics of Severe Thunderstorms and Tornados along with safety measures against these severe weather threats. Statements are being issued on a daily basis from Monday through Friday. Below are the first three Public Information Statements as issued from NWS Taunton:
NOUS41 KBOX 031327
PNSBOX
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
925 AM EDT WED MAY 3 2006
...SEVERE WEATHER AWARENESS WEEK CONTINUES...
...DEFINITION OF A SEVERE THUNDERSTORM...
THE NATIONAL WEATHER SERVICE IN TAUNTON HAS DECLARED THIS WEEK
AS SEVERE WEATHER PREPAREDNESS WEEK IN SOUTHERN NEW ENGLAND. THE
FOLLOWING IS THE THIRD IN A SERIES OF INFORMATIONAL STATEMENTS...
THE DEFINITION OF A SEVERE THUNDERSTORM.
A 'SEVERE THUNDERSTORM' IS DEFINED AS A THUNDERSTORM THAT PRODUCES
WIND GUSTS OF AT LEAST 58 MPH AND/OR HAIL 0.75 INCHES IN DIAMETER OR
LARGER...THE SIZE OF A PENNY OR DIME. SEVERE THUNDERSTORMS CAN AND
OCCASIONALLY DO SPAWN TORNADOES.
A SEVERE THUNDERSTORM WATCH IS ISSUED BY THE STORM PREDICTION CENTER
IN NORMAN OKLAHOMA FOR LARGE PORTIONS OF THE REGION WHEN THE
POTENTIAL EXISTS FOR SEVERE THUNDERSTORMS. A SEVERE THUNDERSTORM
WARNING IS ISSUED BY THE LOCAL FORECAST OFFICE...SUCH AS IN
TAUNTON...WHEN SEVERE THUNDERSTORMS ARE IMMINENT BASED ON RADAR OR
ALREADY OCCURRING BASED ON SPOTTER OBSERVATIONS.
HOW ABOUT HEAVY RAIN? TORRENTIAL DOWNPOURS OF RAIN THAT CAUSE
FLOODING...DAM BREAKS...ETC. ARE NOT PART OF THE DEFINITION OF
'SEVERE.' THEY WOULD CERTAINLY PROMPT THE ISSUANCE OF FLOOD OR FLASH
FLOOD WARNINGS...BUT NOT SEVERE THUNDERSTORM WARNINGS.
DOES FREQUENT LIGHTNING CONSTITUTE A 'SEVERE' THUNDERSTORM? THE FACT
IS THAT EVERY THUNDERSTORM HAS LIGHTNING -- IT IS THE RAPID
EXPANSION OF THE AIR HEATED TO 50,000 DEGREES CELSIUS THAT CAUSES
THE THUNDER IN THE FIRST PLACE. THUS...IF LIGHTNING WERE A CRITERIA
FOR SEVERE THUNDERSTORM WARNINGS...WE WOULD HAVE TO WARN FOR EVERY
THUNDERSTORM WHICH OBVIOUSLY WOULD NOT BE PRACTICAL OR ADVISABLE.
OF COURSE LIGHTNING CAN BE EXTREMELY DANGEROUS AND DEADLY. THE
NATIONAL WEATHER SERVICE WILL ISSUE SHORT TERM FORECASTS AND SPECIAL
WEATHER STATEMENTS REGARDING FREQUENT LIGHTNING ACTIVITY...BUT
SEVERE THUNDERSTORM WARNINGS ARE RESERVED FOR THOSE STORMS THAT
PRODUCE DAMAGING WINDS AND/OR LARGE HAIL.
$$
GAF
NOUS41 KBOX 021526
PNSBOX
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
1125 AM EDT TUE MAY 2 2006
...SEVERE WEATHER PREPAREDNESS WEEK CONTINUES...
...TORNADO SAFETY...
THE NATIONAL WEATHER SERVICE HAS DECLARED THE WEEK OF MAY 1-5, 2006
AS SEVERE WEATHER PREPAREDNESS WEEK FOR SOUTHERN NEW ENGLAND. THE
FOLLOWING IS THE SECOND IN A SERIES OF INFORMATIONAL STATEMENTS
ABOUT SEVERE WEATHER.
TORNADOES DO OCCUR IN SOUTHERN NEW ENGLAND ALMOST EVERY YEAR AND
KNOWING WHAT TO DO IS ESSENTIAL.
A TORNADO WATCH IS ISSUED BY THE STORM PREDICTION CENTER IN NORMAN
OKLAHOMA WHENEVER ATMOSPHERIC CONDITIONS ARE FAVORABLE FOR THE
DEVELOPMENT OF SEVERE THUNDERSTORMS...WITH LARGE HAIL AND DAMAGING
WINDS...SOME OF WHICH COULD SPAWN TORNADOES. THE WATCH OFTEN COVERS
SEVERAL STATES. IT IS YOUR INITIAL WORD THAT DANGEROUS WEATHER IS
POSSIBLE. A SEVERE THUNDERSTORM WATCH MEANS THAT LARGE HAIL OR
DAMAGING WINDS MAY OCCUR. ALTHOUGH TORNADOES CAN FORM WHEN ONLY A
SEVERE THUNDERSTORM WATCH IS IN EFFECT...THE ATMOSPHERE IS MORE
CONDUCIVE TO FORMING TORNADOES IF WE ARE UNDER A TORNADO WATCH.
IF YOUR LOCAL NATIONAL WEATHER SERVICE OFFICE...IN TAUNTON
MASSACHUSETTS FOR EXAMPLE...ISSUES A TORNADO WARNING...IMMEDIATE
ACTION SHOULD BE TAKEN TO PROTECT LIFE AND PROPERTY. A TORNADO
WARNING MEANS THAT A SEVERE THUNDERSTORM IS IN PROGRESS AND THAT A
TORNADO HAS EITHER BEEN SIGHTED OR IS IMMINENT BASED ON DOPPLER
RADAR IMAGERY.
YOUR FIRST TORNADO PREPAREDNESS RULE SHOULD BE TO HAVE A MEANS OF
RECEIVING THE WORD THAT A WATCH OR WARNING IS IN EFFECT. NOAA
WEATHER RADIO...WHICH CAN BE PURCHASED FROM YOUR FAVORITE
ELECTRONICS OUTLET...HAS AN ALARM FEATURE THAT WILL ACTIVATE
WHENEVER A SEVERE WEATHER WATCH OR WARNING IS ISSUED. IT CAN WAKE
YOU UP AT 3 O'CLOCK IN THE MORNING AND THUS IS A TREMENDOUS
NOTIFICATION TOOL. LOCAL RADIO AND TELEVISION STATIONS WILL
BROADCAST THE WARNING...SOMETIMES WITH AN EMERGENCY ALERT TONE. THE
WARNINGS SCROLL ACROSS THE SCREEN ON THE WEATHER CHANNEL ON CABLE
TV. HOWEVER...YOU NEED TO BE WATCHING OR LISTENING IN ORDER TO
RECEIVE THE WARNING VIA COMMERCIAL RADIO OR TV. THAT'S WHY NOAA
WEATHER RADIO IS SO CONVENIENT.
THE GREATEST DANGERS FROM A TORNADO ARE FROM FLYING DEBRIS AND FROM
THE COLLAPSE OF THE ROOF AND/OR WALL STRUCTURE OF A BUILDING. IF IN
A BUILDING...YOU SHOULD MOVE TO THE BASEMENT UNDERNEATH THE
STAIRCASE. IF NO BASEMENT...SEEK SHELTER IN A SMALL INTERIOR ROOM OR
HALLWAY ON THE LOWEST FLOOR. STAY AWAY FROM WINDOWS AND EXTERIOR
DOORS. DO NOT OPEN THE WINDOWS. IF POSSIBLE...PLACE SOMETHING OVER
YOUR HEAD SUCH AS A COAT OR BLANKET FOR EXTRA PROTECTION. IN
SCHOOLS...AVOID THE CAFETERIA...GYMNASIUM...OR AUDITORIUM BECAUSE OF
THE WIDE-SPAN ROOFS THAT CAN COLLAPSE. YOU SHOULD GO TO THE
INTERIOR HALLWAY OUTSIDE OF THE CLASSROOMS.
DO NOT STAY IN A MOBILE HOME OR ANY TYPE OF TEMPORARY SHELTER. SEEK
SHELTER IN A STURDY STRUCTURE. IF NONE IS AVAILABLE...GO TO A DITCH
OR NEARBY RAVINE. TAKE THE PROTECTIVE POSITION ON YOUR ELBOWS AND
KNEES WITH YOUR HANDS OVER YOUR HEAD. NEVER ATTEMPT TO OUTRUN A
TORNADO IN A VEHICLE SINCE THEY CAN EASILY BECOME AIRBORNE. IN
1995...3 PEOPLE WERE KILLED IN GREAT BARRINGTON MASSACHUSETTS WHEN
THEIR AUTOMOBILE WAS LIFTED UP IN THE AIR AND SMASHED DOWN TO THE
GROUND. DO NOT SEEK SHELTER UNDER AN OVERPASS. THE STRUCTURAL
INTEGRITY OF OVERPASSES IS UNKNOWN...PLUS THE BERNOULLI PRINCIPLE
CAN LEAD TO ACCELERATION OF THE WIND THROUGH THE EMBANKMENT.
AFTER THE STORM...IF A TORNADO HAS STRUCK YOUR NEIGHBORHOOD...PLEASE
REPORT IT TO LOCAL LAW ENFORCEMENT OFFICIALS FOR RELAY TO THE
NATIONAL WEATHER SERVICE. TURN OFF THE GAS AT THE MAIN SWITCH TO
YOUR BUILDING. IF LIVE ELECTRICAL WIRES ARE DOWN...TURN OFF POWER
AT THE MAIN SWITCH. INSTRUCT PEOPLE NOT TO TOUCH LOOSE ELECTRICAL
WIRES. FOOD...CLOTHING...AND SHELTER WILL BECOME AVAILABLE AT
AMERICAN RED CROSS SHELTERS.
$$
FIELD
NOUS41 KBOX 011457
PNSBOX
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
1055 AM EDT MON MAY 1 2006
...SEVERE WEATHER PREPAREDNESS WEEK...
...DOWNBURST WINDS FROM SEVERE THUNDERSTORMS CAN BE POWERFUL...
THE NATIONAL WEATHER SERVICE HAS DECLARED THE WEEK OF MAY 1-5, 2006
AS SEVERE WEATHER PREPAREDNESS WEEK FOR SOUTHERN NEW ENGLAND. THE
FOLLOWING IS THE FIRST IN A SERIES OF INFORMATIONAL STATEMENTS ABOUT
SEVERE WEATHER.
WHILE NOT AS NOTORIOUS...OR PERHAPS AS SPECTACULAR TO WITNESS AS A
TORNADO...STRAIGHT-LINE WINDS ARE RESPONSIBLE FOR MOST THUNDERSTORM
WIND DAMAGE...ESPECIALLY ACROSS SOUTHERN NEW ENGLAND.
A DOWNBURST IS A STRONG AND RELATIVELY SMALL AREA OF RAPIDLY
DESCENDING AIR BENEATH A THUNDERSTORM. IT CAN RESULT FROM STRONGER
JET STREAM WINDS BEING TRANSPORTED DOWNWARD TO THE SURFACE. OR IT
CAN RESULT AS AIR WITHIN THE DOWNBURST IS COOLED SIGNIFICANTLY AS
RAIN EVAPORATES IN INITIALLY DRIER AIR. THIS COOL...THUS DENSE...
AIR SINKS RAPIDLY TO THE SURFACE. A DOWNBURST IS DIFFERENTIATED
FROM A COMMON THUNDERSTORM DOWNDRAFT BECAUSE THE WINDS IT PRODUCES
HAVE THE POTENTIAL TO CAUSE DAMAGE ON OR NEAR THE GROUND. SURFACE
DAMAGE PATTERNS HAVE SHOWN THAT WHETHER THE WINDS ARE STRAIGHT OR A
LITTLE BIT CURVED...THEY TEND TO SPREAD OUT...OR DIVERGE...
CONSIDERABLY AS THEY REACH THE SURFACE. CONVERSELY...DAMAGE PATTERNS
RESULTING FROM A TORNADO GENERALLY CONVERGE TOWARD A NARROW CENTRAL
TRACK.
INTENSE DOWNBURSTS CAN BE PHENOMENAL. SPEEDS HAVE BEEN CLOCKED AS
HIGH AS 175 MPH A FEW YEARS AGO NEAR MOREHEAD CITY NORTH CAROLINA
AND AT 158 MPH AT ANDREWS AIR FORCE BASE IN MARYLAND IN 1986.
CLOSER TO HOME...104 MPH DOWNBURST WINDS WERE MEASURED AT BOTH
WORCESTER MASSACHUSETTS ON MAY 31 1998 AND WHITMAN MASSACHUSETTS ON
MAY 21 1996. STRONG DOWNBURSTS WILL DEFINITELY CAUSE ROARING SOUNDS
AND PEOPLE MAY OFTEN REFER TO A SOUND LIKE A FREIGHT TRAIN...TERMS
TYPICALLY ASSOCIATED WITH TORNADOES. ALTHOUGH DOWNBURSTS ARE NOT
TORNADOES...THEY CAN CAUSE DAMAGE EQUIVALENT TO THAT OF A SMALL TO
MEDIUM TORNADO. AFTER ALL...WIND IS WIND.
DOWNBURSTS ARE CLASSIFIED AS EITHER MACROBURSTS OR MICROBURSTS...
DEPENDING ON THE AREAL EXTENT OF THE DAMAGING WIND SWATH.
A MACROBURST/S DAMAGE EXTENDS HORIZONTALLY FOR MORE THAN 2.5 MILES.
A MICROBURST IS A SMALL DOWNBURST WITH ITS DAMAGING WINDS EXTENDING
2.5 MILES OR LESS. THE SMALL HORIZONTAL SCALE AND SHORT TIME SPAN
OF A MICROBURST MAKES IT PARTICULARLY HAZARDOUS TO AVIATION.
THE NATIONAL WEATHER SERVICE ISSUES SEVERE THUNDERSTORM WARNINGS FOR
THUNDERSTORMS THAT ARE EXPECTED TO PRODUCE DAMAGING WIND GUSTS OF
58 MPH OR GREATER...OR HAIL THAT IS THREE QUARTERS OF AN INCH /0.75
INCHES/ OR GREATER IN DIAMETER.
$$
GAF
Respectfully Submitted,
Robert Macedo (KD1CY)
ARES SKYWARN Coordinator
Eastern Massachusetts ARES Section Emergency Coordinator
Pager #: (508) 354-3142
Home Phone #: (508) 994-1875 (After 6 PM)
Home/Data #: (508) 997-4503 (After 6 PM)
Work Phone #: 1-800-445-2588 Ext.: 72929 (8 AM-5 PM)
Email Address: rmacedo@rcn.com
http://users.rcn.com/rmacedo
Read previous mail | Read next mail
| |
