Tornadoes in MA

[StormNine]

This area has had a dance with tornadoes before.  My weather book that came out back in 1997 mentioned that MA has a pretty high rate of F2+ tornadoes.  Part of it is the small size of the state, but they have been hit hard a few times in recorded history.  Worchester MA was hit by a very bad tornado that killed 94 back in the 1950's. 

[CT_Yankee]

The ASOS (most...at least) do have equipment that can automatically detect lightning and its distance from the site...its frequency and type. That's when you'll see something like... "FRQ LTG ICCG NE-E" in the remarks section of an observation...which would indicate Frequent Lightning...In-Cloud and Cloud-to-Ground...from Northeast to East of the observation point.

Some...but not all ASOS sites have a human observer on-site that can augment the data if necessary. This is mostly at larger airports...and are contract employees from the FAA that do have extensive observation training. Most times...its not needed...but sometimes especially during an active situation extra remarks can be added about certain cloud types or data can be corrected if there is a malfunction somewhere in the automated sensors...etc. They also are the ones that report snowfall amount and depth at ASOS sites...which we've discussed before as being a point of inconsistency at times during the winter.

A contract observer on-site can also report a Funnel Cloud (FC) or Tornado (+FC) within an observation. The automated equipment can NOT detect this...this is something that must be augmented into an ob by the observer...so you would only ever see them at ASOS sites that have an observer there. KBAF does have an observer...and the observer there witnessed a funnel cloud that developed and lasted for one minute.

Here is the raw METAR...
KBAF 012024Z 30005KT 1 1/4SM R20/4500VP6000FT FC +TSRA BKN024 BKN030 OVC065 26/22 A2984 RMK FUNNEL CLOUD B23 E24 AO2 LTG DSNT NW-E TSB1958RAB00 P0023

Notice the "FC" in the observation. Then...in the Remarks section...the observer added additional details...indicating the funnel cloud began at "B23" (:23 after the hour) and ended at "E24" (:24 after the hour). That is followed by the Lightning Detection information (which again is automated) indicating lightning was distant in the horizon from the NW to the E.

If you ever look at a raw METAR...if it says "AUTO" at the beginning of the report...it means its a completely automated sensor with no observer on-site and thus human input (at least at that report time...some sites don't keep an observer on-site 24/7/365). If it doesn't...then an observer was present and may have augmented data to the original report. ALL funnel clouds and tornadoes that would be observed would have to fall under that category.

Thanks Kevin!  This answers a lot of questions.

I am still wondering how "thunder" or "thunderstorm" is determined....I'm guessing it's either an on-site observer or a certain proximity of lightning....

[CT_Yankee]

This area has had a dance with tornadoes before.  My weather book that came out back in 1997 mentioned that MA has a pretty high rate of F2+ tornadoes.  Part of it is the small size of the state, but they have been hit hard a few times in recorded history.  Worchester MA was hit by a very bad tornado that killed 94 back in the 1950's.  

Interesting:

http://www.washingtonpost.com/blogs/capital-weather-gang/post/springfield-tornado-not-unprecedented-in-massachusetts/2011/06/02/AGMp1FHH_blog.html

Obviously the facts speak for themselves, but this comes as a bit of a surprise to me considering I lived the better part of my life in that region and just don't remember too many (or any at all) "red-letter" and/or wall-to-wall coverage days like we have here at least a couple of times a year.   It just seems like tornadoes are much more of an issue here.

[Kevin]

Thanks Kevin!  This answers a lot of questions.

I am still wondering how "thunder" or "thunderstorm" is determined....I'm guessing it's either an on-site observer or a certain proximity of lightning....

No problem!

Here's the protocol for lightning detection and thunderstorm reporting...technically its derived from the automated lightning detection...not thunder itself...but if an observer is on-site and hears thunder...a thunderstorm can then be augmented into an ob without the automated sensor reading if its not being detected (probably pretty rare to see that).

If the Lightning Detection picks up lightning greater than 10nm from the observation point...No thunder/thunderstorm is reported...and only "LTG DSNT" is seen in the Remarks section.

If the Lightning Detection picks up lightning between 5 and 10nm from the observation point...that is reported as "VCTS"...or Thunderstorm in the Vicinity. If precipitation is also occurring within this range at the observation site...I believe this can be augmented in the ob as a Thunderstorm ("TS") occurring.

If the Lightning Detection picks up lightning less than 5nm from the observation point...that is then reported as a thunderstorm ("TS"). Precipitation type (if falling) is added immediate following the Thunderstorm Report (TSRA...TSSN...etc).

If there is no automated lightning detection at the site...but an observer is present...the observer is responsible for reporting thunderstorms when lightning is observed or thunder is heard. If neither an observer is present or there is no lightning detection system at the site...that site can not report a thunderstorm at all.

[Kevin]

...THREE TORNADOES CONFIRMED ON JUNE 1 2011 IN MASSACHUSETTS...

...EF3 TORNADO CONFIRMED FROM WESTFIELD TO CHARLTON...

LOCATION...WESTFIELD TO CHARLTON IN HAMPDEN AND WORCESTER COUNTIES
DATE...JUNE 1 2011
ESTIMATED TIME...417 PM TO 527 PM EDT
MAXIMUM EF-SCALE RATING...EF3
ESTIMATED MAXIMUM WIND SPEED...160 MPH
MAXIMUM PATH WIDTH...ONE HALF MILE
PATH LENGTH...39.0 MILES
BEGINNING LAT/LON...42.10N / 72.75W
ENDING LAT/LON...42.10N / 71.99W
* FATALITIES...4
* INJURIES...200

* 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 TAUNTON MASSACHUSETTS HAS
CONFIRMED AN EF3 TORNADO FROM WESTFIELD TO CHARLTON MASSACHUSETTS
ON JUNE 1 2011.

A SUPERCELL THUNDERSTORM DEVELOPED OVER WESTERN MASSACHUSETTS
WEDNESDAY AFTERNOON. THIS STORM STRENGTHENED AND PRODUCED A LONG-
LIVED...VERY SIGNIFICANT TORNADO...THAT DID EXTENSIVE DAMAGE ACROSS
SOUTHWEST AND SOUTH-CENTRAL MASSACHUSETTS.

THIS STORM WILL BE NOTED NOT ONLY FOR ITS INTENSITY...BUT ALSO FOR
THE LENGTH OF THE CONTINUOUS DAMAGE PATH...APPROXIMATELY 39 MILES.
THE TORNADO WAS ALSO VERY WIDE AT SOME POINTS...REACHING A MAXIMUM
WIDTH OF ONE-HALF MILE.

THE TORNADO FIRST TOUCHED DOWN IN THE MUNGER HILL SECTION OF
WESTFIELD WITH DAMAGE MAINLY LIMITED TO TREES...MANY UPROOTED AND
SNAPPED. THE ROOF OF MUNGER HILL ELEMENTARY SCHOOL WAS ALSO
DAMAGED. THE TORNADO RAPIDLY INTENSIFIED AS IT MOVED INTO WEST
SPRINGFIELD. THE TORNADO CAUSED EXTENSIVE DAMAGE TO INDUSTRIAL
BUILDINGS AND HOMES. SEVERAL BUILDINGS HAD THEIR ROOFS REMOVED BY
THE TORNADO...A FEW STRUCTURES COLLAPSED...AND SEVERAL MULTI-
STORY BUILDINGS LOST THEIR UPPER STORIES.

THE TORNADO THEN CROSSED THE CONNECTICUT RIVER AT THE MEMORIAL
AVENUE BRIDGE AND INTO THE CITY OF SPRINGFIELD. HERE THE TORNADO
PRODUCED EXTENSIVE DAMAGE TO THE SOUTH SIDE OF THE DOWNTOWN AREA
WITH MANY HOMES DESTROYED. IN ADDITION COMMERCIAL BRICK BUILDINGS
SUSTAINED MAJOR DAMAGE. ROOFS WERE REMOVED FROM MANY OF THESE
LARGE COMMERCIAL STRUCTURES. THE TORNADO ALSO PRODUCED SEVERE
STRUCTURAL DAMAGE TO TOWN HOMES AND APARTMENTS NEAR SPRINGFIELD
COLLEGE. THE TORNADO CONTINUED MOVING EAST INTO THE ISLAND POND
SECTION OF SPRINGFIELD...WHERE CATHEDRAL HIGH SCHOOL SUSTAINED
SIGNIFICANT DAMAGE...AND MANY HOMES IN THIS PART THE CITY WERE
COMPLETELY DESTROYED.

THE TORNADO CONTINUED TO MOVE EAST THROUGH WILBRAHAM NEAR THE
WILBRAHAM-HAMPDEN TOWN LINE PRODUCING NEARLY COMPLETE
DEFORESTATION AND SIGNIFICANT DAMAGE TO NEARBY STRUCTURES.

THE TORNADO THEN CONTINUED DIRECTLY THROUGH THE MIDDLE OF THE
TOWN OF MONSON. IN MONSON WIDESPREAD DAMAGE OCCURRED TO COMMERCIAL
AND RESIDENTIAL BUILDINGS...WITH MANY HOMES COMPLETELY DESTROYED.
THE ROOF OF MONSON HIGH SCHOOL WAS DESTROYED. FORESTED PARTS OF
TOWN EXPERIENCED NEARLY COMPLETE DEFORESTATION AND IN SOME
LOCATIONS TREE BARK WAS STRIPPED FROM REMAINING TRUNKS.

THE TORNADO MOVED ACROSS THE BRIMFIELD STATE FOREST WHERE IT
REACHED IT MAXIMUM WIDTH OF APPROXIMATELY ONE-HALF MILE. ADDITIONAL
SIGNIFICANT DAMAGE OCCURRED BOTH TO STRUCTURES AND FORESTED AREAS
FOR MANY MILES BEFORE THE TORNADO REACHED THE SOUTHBRIDGE AIRPORT.
HERE NUMEROUS AIRCRAFT WERE LIFTED OFF THE GROUND AND INTO THE
WOODS EAST OF THE AIRPORT.

THE TORNADO THEN MOVED EAST BEFORE LIFTING IN THE SOUTHWEST PART
OF CHARLTON.

&&

...EF1 TORNADO CONFIRMED IN WILBRAHAM...

LOCATION...WILBRAHAM IN HAMPDEN COUNTY
DATE...JUNE 1 2011
ESTIMATED TIME...632 PM TO 640 PM EDT
MAXIMUM EF-SCALE RATING...EF1
ESTIMATED MAXIMUM WIND SPEED...90 MPH
MAXIMUM PATH WIDTH...200 YARDS
PATH LENGTH...3.6 MILES
BEGINNING LAT/LON...42.14N / 72.48W
ENDING LAT/LON...42.15N / 72.40W
* 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 TAUNTON MASSACHUSETTS HAS
CONFIRMED AN EF1 TORNADO IN WILBRAHAM ON JUNE 1 2011.

A NATIONAL WEATHER SERVICE SURVEY TEAM CONFIRMED THAT AN EF1
TORNADO TOUCHED DOWN IN THE NORTHWEST CORNER OF WILBRAHAM. THE TORNADO
CONTINUED EAST CROSSING MAIN STREET AND MOUNTAIN ROAD...BUT
REMAINED SOUTH OF ROUTE 20. MOST OF THE DAMAGE WAS TO TREES WITH
LARGE LIMBS SNAPPED OFF...AS WELL AS NUMEROUS TREES DOWNED.
SEVERAL WERE UPROOTED.

&&

...EF1 TORNADO CONFIRMED IN NORTH BRIMFIELD...

LOCATION...NORTH BRIMFIELD IN HAMPDEN COUNTY
DATE...JUNE 1 2011
ESTIMATED TIME...654 PM TO 657 PM EDT
MAXIMUM EF-SCALE RATING...EF1
ESTIMATED MAXIMUM WIND SPEED...90 MPH
MAXIMUM PATH WIDTH...100 YARDS
PATH LENGTH...1.3 MILES
BEGINNING LAT/LON...42.14N / 72.23W
ENDING LAT/LON...42.15N / 72.20W
* 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 TAUNTON MASSACHUSETTS HAS
CONFIRMED AN EF1 TORNADO IN NORTH BRIMFIELD ON JUNE 1 2011.

A NATIONAL WEATHER SERVICE SURVEY TEAM CONFIRMED THAT A SECOND EF1
TORNADO TOUCHED DOWN NORTH OF BRIMFIELD WEST OF ROUTE 19. THIS
TORNADO CROSSED ROUTE 19 AND LIFTED NEAR TOWER HILL ROAD. THE
DAMAGE WAS SURVEYED ON THE GROUND AND BY AIRCRAFT. THE DAMAGE
CONSISTED OF TREES WITH LARGE LIMBS SNAPPED OFF...AS WELL AS
NUMEROUS TREES DOWNED...A FEW OF WHICH WERE UPROOTED. THIS TORNADO
IS FROM THE SAME PARENT THUNDERSTORM THAT PRODUCED THE TORNADO IN
NORTH WILBRAHAM.

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

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.

THE NATIONAL WEATHER SERVICE WOULD LIKE TO THANK THE VARIOUS STATE
AND LOCAL AGENCIES AND THE CIVIL AIR PATROL FOR ALL OF THEIR
ASSISTANCE IN COMPLETING THESE STORM SURVEYS.

[CT_Yankee]

PATH LENGTH...39.0 MILES