Alert archive / Maine / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 607

July 6, 2011Penobscot County, Piscataquis County, Maine

The Storm Prediction Center issued this severe thunderstorm watch at Jul 6, 2011, 5:35 PM EDT for Penobscot County, Piscataquis County, Maine. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Jul 6, 2011, 5:35 PM EDT (21:35 UTC)
Expired
Jul 6, 2011, 8:38 PM EDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt

Counties Penobscot County, ME, Piscataquis County, ME

The radar

The Caribou radar (KCBW), 105 km from the middle of the area, began a volume at 21:37 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jul 6, 5:49 PM EDTSevere Thunderstorm WarningCARPiscataquis, Somerset56 min
Jul 6, 6:32 PM EDTSevere Thunderstorm WarningCARPenobscot, Piscataquis58 min
Jul 6, 6:42 PM EDTSevere Thunderstorm WarningCARPenobscot, Piscataquis63 min
Jul 6, 7:06 PM EDTSevere Thunderstorm WarningCARAroostook, Penobscot, Piscataquis54 min
Jul 6, 7:12 PM EDTSevere Thunderstorm WarningCARAroostook, Hancock, Penobscot, Washington63 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Caribou, ME (KCAR), launched 12:00Z, 9.6 hours before the alert went out and 165 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Caribou, ME at 12:00Z on 2011-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 51 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Caribou, ME at 12:00Z on 2011-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 158 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
51 J/kg
Mixed-layer CIN
-129 J/kg
Mixed-layer LCL
1368 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
158 m²/s²
0-3 km storm-relative helicity
168 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

861 
WWUS20 KWNS 062135
SEL7  
SPC WW 062135
MEZ000-070200-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 607
NWS STORM PREDICTION CENTER NORMAN OK
535 PM EDT WED JUL 6 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 

       CENTRAL AND EASTERN MAINE

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 535 PM UNTIL
1000 PM EDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45
STATUTE MILES EAST AND WEST OF A LINE FROM 90 MILES NORTH OF
BANGOR MAINE TO 10 MILES SOUTHEAST OF BANGOR MAINE.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU7).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 605...WW 606...

DISCUSSION...ORGANIZED COMPLEX OF TSTMS PRECEDING SHORT WAVE TROUGH
WILL CONTINUE EWD THIS EVENING AMIDST A MODERATELY UNSTABLE AIR MASS
WITH MLCAPE OF 1000-1500 J/KG.  GIVEN THE 40-45 KT EWD MOTION OF 
ONGOING STORMS...THE POTENTIAL FOR DAMAGING WINDS WILL EXIST AS
ACTIVITY PROGRESSES EWD ACROSS THE WATCH AREA.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 27035.


...MEAD

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 1:04 PM EDTMesoscale DiscussionSPCOxford56 min
Jul 6, 1:29 PM EDTSevere Thunderstorm WatchSPCFranklin, Oxford, Somerset8 hr
Jul 6, 6:03 PM EDTMesoscale DiscussionSPCFranklin, Oxford, Penobscot, Piscataquis, Somerset87 min

Nearby

Severe Thunderstorm Watches in Maine, 2011Every severe thunderstorm watch in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.